Re: Balun Questions
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It’s quite practical to use 25 to 35 mm radius bends of RG400 for large ferrite cores including both the one-piece and the snap-on varieties. RG400 has the same diameter as RG-58, i.e. 0.195”. See K9YC’s tutorial here:
http://audiosystemsgroup.com/RFI-Ham.pdf All of the RF common mode chokes I have made using small cable (i.e. RG400 through RG6) use radii of 1-3 inches with the RG6 tending toward 3” and greater due to the foam dielectric. --- Chuck, AE4CW From: Mel Farrer [mailto:[hidden email]] Sent: Sunday, February 07, 2016 17:54 To: Chuck Catledge <[hidden email]>; 'Guy Olinger K2AV' <[hidden email]>; 'Robert Nobis' <[hidden email]> Cc: [hidden email]; 'Ron D'Eau Claire' <[hidden email]> Subject: Re: [Elecraft] Balun Questions SORRY, but the min static bending radius for RG-303 is 25 mm and RG-400 is 35 mm. For torroid wrap which is better????? Mel, K6KBE _____ From: Chuck Catledge <[hidden email] <mailto:[hidden email]> > To: 'Guy Olinger K2AV' <[hidden email] <mailto:[hidden email]> >; 'Robert Nobis' <[hidden email] <mailto:[hidden email]> > Cc: [hidden email] <mailto:[hidden email]> ; 'Ron D'Eau Claire' <[hidden email] <mailto:[hidden email]> > Sent: Sunday, February 7, 2016 2:31 PM Subject: Re: [Elecraft] Balun Questions At hamfests around the Southeast, surplus RG400 is often found in terminated cables (usually BNC or N) in lengths up to around 20 feet. The price I've paid is always less than $1.00 per foot, sometimes much less. I've used it to make dozens of RF chokes (1:1 baluns). The small size of RG400 allows the use of a single medium to large clamp-on #31 ferrite that works effectively from 10-160M, conditioned by the number of turns. The large snap-on ferrite will accommodate 10-12 turns; the medium snap-on will handle 5-6 turns. Jim, K9YC's tutorials are excellent. Consult the Fair-Rite website for additional technical data. BTW, the Teflon dielectric allows easy soldering in PL-259s with RG-58 reducers without any fear of melting the dielectric. --- Chuck, AE4CW -----Original Message----- From: Guy Olinger K2AV [mailto:[hidden email] <mailto:[hidden email]> ] Sent: Sunday, February 07, 2016 01:08 To: Robert Nobis <[hidden email] <mailto:[hidden email]> > Cc: [hidden email] <mailto:[hidden email]> ; Ron D'Eau Claire <[hidden email] <mailto:[hidden email]> >; Guy Olinger K2AV <[hidden email] <mailto:[hidden email]> > Subject: Re: [Elecraft] Balun Questions RG303 is not rated for the tight bends. RG400 with its fine stranded center conductor is rated for corner bends in aircraft wiring harnesses and will not deform the dielectric within the bends. I would not wind any solid center conductor coax on a toroid. I would only buy cut lengths of RG400 after the lengths for a project are known. Some number of such suppliers on eBay. One currently listed at 1.98 per foot: http://www.ebay.com/itm/RG400-Coaxial-Cable-Mil-spec-by-the-ft-US-supplier-/251260159394?hash=item3a8045c5a2:g:WpAAAOxy43FRafUe True it ain't ham cheep. The good stuff that lasts and lasts almost never is. Back in the early days of eBay I came by a 142' length of RG400 for $25. That's $0.178 a foot I also came by bundles of miscellaneous 6 foot to 15 foot jumpers with various connectors on end for similar ridiculous low prices per foot. The silvered copper strands stand up to migration of dampness in a way not possible with same size copper strands minus the silvering. I have *measured* the dry RF resistance at 1.83 MHz of a 67 foot length of corroded #14 stranded plain copper at 62 ohms. When new this wire had resistance at RF of less than an ohm. I have never found the silvered copper equivalent in anything remotely approaching that degraded state. RG400 wound on the proper core for the job will last a lifetime. 73, Guy K2AV On Saturday, February 6, 2016, Robert Nobis <[hidden email] <mailto:[hidden email]> > wrote: > I have used RG303/U for chokes. A bit smaller diameter than RG400 > (0.170 versus 0.195 inches). RG303/U has a solid copper center > conductor that is silver plated. The shield for RG303 is also silver > plated copper. The jacket is Class 9 Teflon. Also the dielectric material is teflon. > > 73, > > > Bob Nobis - N7RJN > [hidden email] <mailto:[hidden email]> > > > > On Feb 6, 2016, at 17:49, Guy Olinger K2AV <[hidden email] <mailto:[hidden email]> > wrote: > > > > If one wants a small 50 ohm coax that will take QRO with a very > > large margin and was *designed* for bending and use in aircraft > > wiring > harnesses > > then use RG400 to wind around your core. RG400 uses a fine stranded > > silvered copper center conductor that is more flexible than its > > Teflon dielectric. It has a double shield made from silvered copper strands. > > > > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] <mailto:[hidden email]> This list hosted by: http://www.qsl.net <http://www.qsl.net/> Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] <mailto:[hidden email]> ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email]
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Chuck, AE4CW |
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I am speaking of the radius of the coax bend. To have a coax bend
radius of 3" the torroid would be huge.......the size of a large coffee can. A 3" OD, x 1.5" ID torroid would typically have a winding radius of less than ~1", even with 2 stacked cores. For my "ugly balun" project I use 4" ID PVC which has an OD of ~4.5" and which provides a bend radius of 2.25". 73 Bob, K4TAX On 2/7/2016 10:32 PM, Chuck Catledge wrote: > It’s quite practical to use 25 to 35 mm radius bends of RG400 for large ferrite cores including both the one-piece and the snap-on varieties. RG400 has the same diameter as RG-58, i.e. 0.195”. See K9YC’s tutorial here: > > http://audiosystemsgroup.com/RFI-Ham.pdf > > All of the RF common mode chokes I have made using small cable (i.e. RG400 through RG6) use radii of 1-3 inches with the RG6 tending toward 3” and greater due to the foam dielectric. > > --- > > Chuck, AE4CW > > From: Mel Farrer [mailto:[hidden email]] > > Subject: Re: [Elecraft] Balun Questions > > > > SORRY, but the min static bending radius for RG-303 is 25 mm and RG-400 is 35 mm. For torroid wrap which is better????? > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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I just completed a 160/80M common mode choke made from 6 type 31
cores. Each core is 1/2" inside diameter, 1" outside diameter, and 1" long. (12.5mm, 25mm, 25mm). There are four windings of RG58 and I think this design is in agreements with Jim Brown, K9YC's RFI-ham.pdf. The choke hangs just below the feed point of my 160M dipole/80M inverted V. The antennas are at 44' (12M). The choke appears to work well and seems to have knocked the noise levels on 160M down an S unit or two. I was able to hear and work DX during the CQ contest further away than before. The cores are separated by about an inch each and the total diameter of the windings is about 8 inches (200mm). I don't think you need to wrap tightly to the cores. I have no test information, lacking equipment. 73 Bill AE6JV On 2/7/16 at 9:03 PM, [hidden email] (Bob McGraw K4TAX) wrote: >I am speaking of the radius of the coax bend. To have a coax >bend radius of 3" the torroid would be huge.......the size of a >large coffee can. A 3" OD, x 1.5" ID torroid would typically >have a winding radius of less than ~1", even with 2 stacked >cores. For my "ugly balun" project I use 4" ID PVC which has >an OD of ~4.5" and which provides a bend radius of 2.25". ----------------------------------------------------------------------- Bill Frantz | "The only thing we have to | Periwinkle (408)356-8506 | fear is fear itself." - FDR | 16345 Englewood Ave www.pwpconsult.com | Inaugural address, 3/4/1933 | Los Gatos, CA 95032 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Bob McGraw - K4TAX
Bob,
It appears that you're of a mind that the winding (coax) is tightly wound around the core. That's not how some guys are doing it. It's just loosely looped through the core. See fig. 36 in Jim's paper. Wes On 2/7/2016 10:03 PM, Bob McGraw K4TAX wrote: > I am speaking of the radius of the coax bend. To have a coax bend radius of > 3" the torroid would be huge.......the size of a large coffee can. A 3" OD, x > 1.5" ID torroid would typically have a winding radius of less than ~1", even > with 2 stacked cores. For my "ugly balun" project I use 4" ID PVC which has > an OD of ~4.5" and which provides a bend radius of 2.25". > > 73 > Bob, K4TAX > > > > On 2/7/2016 10:32 PM, Chuck Catledge wrote: >> It’s quite practical to use 25 to 35 mm radius bends of RG400 for large >> ferrite cores including both the one-piece and the snap-on varieties. RG400 >> has the same diameter as RG-58, i.e. 0.195”. See K9YC’s tutorial here: >> >> http://audiosystemsgroup.com/RFI-Ham.pdf >> >> All of the RF common mode chokes I have made using small cable (i.e. RG400 >> through RG6) use radii of 1-3 inches with the RG6 tending toward 3” and >> greater due to the foam dielectric. >> >> --- >> >> Chuck, AE4CW >> >> From: Mel Farrer [mailto:[hidden email]] >> >> Subject: Re: [Elecraft] Balun Questions >> >> >> SORRY, but the min static bending radius for RG-303 is 25 mm and RG-400 is 35 >> mm. For torroid wrap which is better????? >> >> > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Jim Allen
This doesn't answer your details, but what I did to test the one I made
was simply to compare it to the balun in my manual roller inductor tuner. I used a short coax jumper between the tuner and the homebrew balun. Dick, n0ce On 2/6/2016 12:06 PM, Jim Allen wrote: > Ok, so this morning, I went out to the shack and whipped up a balun, from a G3TXQ design I found on the website of W5DXP.com. It is coax wrapped around a ferrite core, with appropriate connectors in a plastic weathertight box. I used RG8X coax, a 2.4" core, not sure exactly what mix, and 11 turns. > > How do I test this device to get its properties, impedance at various frequencies, etc? > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Let's do some basic thinking. The balun you made with a ferrite torroid and a length of coax is a straight piece of coax with the two ends supposedly isolated for CMC common mode current., right? How do you make a simple measurement on the lowest frequency? Expensive equipment, right? Well, what is the next best way to determine the isolation at RF, Hummm. If I measure the inductance across the two ends of the balun that is shield to shied to make it easy, the ferrite increases the inductance of the many turns through the core, right? If you take the number in uH and put it into the: ( Xl= 6.28*F(HZ)*inductance(H)), formula you get an equivalent reactance in ohms at the frequency of interest. Yes, I know there are other factors, but it gives you a figure of merit against any other current choke baluns, or other designs you would like to try. Remember More is better. Funnnnnn.
Mel, K6KBE From: Richard Fjeld <[hidden email]> To: [hidden email] Sent: Monday, February 8, 2016 12:57 PM Subject: Re: [Elecraft] Balun Questions This doesn't answer your details, but what I did to test the one I made was simply to compare it to the balun in my manual roller inductor tuner. I used a short coax jumper between the tuner and the homebrew balun. Dick, n0ce On 2/6/2016 12:06 PM, Jim Allen wrote: > Ok, so this morning, I went out to the shack and whipped up a balun, from a G3TXQ design I found on the website of W5DXP.com. It is coax wrapped around a ferrite core, with appropriate connectors in a plastic weathertight box. I used RG8X coax, a 2.4" core, not sure exactly what mix, and 11 turns. > > How do I test this device to get its properties, impedance at various frequencies, etc? > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Robert Nobis - N7RJN
Robert Nobis wrote:
> After reviewing specs from several manufacturers, the “recommended” minimum bend radius for RG303 and RG400 is essentially the same at 1.0 inches. Hi Robert, I have wrapped RG400 on a two stack of FT240 form factor toroids with never an issue, without any change in electrical characteristics I could measure. These were a little less than a half inch radius, something I would never try with 303 or 142. A one inch radius or two inch diameter winding, per the listings you have quoted, would hang loose on most forms. In effect this specifies the 303/142/400 cables useless for winding on toroid cores of any HF suitable size in use by hams, including even the monumental T500A series toroids. ***However,*** I respectfully suggest that the minimum bending radius that you see published for RG400 can be ignored for ham purposes at HF and low VHF, and common sense is better suited to the problem. IMHO the ANSI standard (ANSI/SCTE 39 2007) uses a crude method better suited to measuring metallic sheathed cables, and ignores testing the needed characteristics directly, simply to avoid testing cost and complexity. I also suggest that everyone carefully study the ANSI standard until it is clear what they are doing mechanically and see what they are actually measuring: http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007.pdf The method of measuring is in section 4. They are looking for a limit of 1% surface deformity when bending. In the case of RG400 with .195 inch OD, that would be 2/1000 of an inch (yes, that's three zeros, two one thousandths of an inch) bending deformity at the surface of the teflon jacket, or half the thickness of an average human hair. Anyone who works with teflon knows that the teflon jacket on the outside of the bend will stretch and the teflon on the inside of the bend will bunch, due to the difference in the radius, and particularly due to it being a soft material with no constraint to its outside surface. And there is the problem of managing to measure the thickness of something soft like teflon so as not to compress the teflon 2 mils during the measurement of something with a curved surface. The teflon dielectric between the inside of the shield and the center conductor, all we care about, is confined by the double shield, which opposes the teflon's tendency to deform. Further, the difference in the radius is smaller inside the shield, dividing down the differential measured at the surface of the jacket. The 19 strand center conductor in RG400 will easily follow the teflon in multiple bendings. The solid center conductor versions (303,142) to a degree will remember their first bend and will apply that deformity in the second and later bends, accumulating deformity at that point in the cable unless the second bend is identical to the first. That is why you see "once" or "bend once" in some of the listings for RG303 and RG142. I have no argument with the "bend once" specification in the 303 and 142 listings. It's relates to the reason I use RG400. RG400 is the only coax listed for certified aircraft installations in a lot of aircraft service vendor's web pages. I find 142 mentioned a few times as being easier to fit with connectors. I have not seen 303 mentioned on an aircraft service vendor web page. 73, Guy K2AV ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Hi Guy,
Thank you. It is interesting that the ANSI test is based on physical “outer surface" deformity, rather than electrical (rf) performance. Although there is probably a degree of correlation between physical deformity and electrical (rf) performance. I agree the ANSI spec outlines a rather crude test. The data I provided came from several manufacturers of coax. I just wanted to point out that the manufacturer’s specifications for both RG303 and RG400 are the same at a 1.0 inch static bending radius. They did not indicate how they came up with these specifications. I believe there is plenty of margin in these specified values that may be required for use in military applications, since both cables are MIL spec rated. However, for ham radio purposes, I believe these specs can be safely ignored, within reason. Although, I probably would not try to bend either RG303 or RG400 any tighter than maybe 0.40 to 0.45 inches. I have used RG303/U because that is what I had. If I had RG400/U, I would have used that. In my case, I have seen no measurable performance issues with the tightly wound chokes that I have made with RG303/U. If care is taken in winding the chokes, I feel either type of coax will do the job. Maybe if I find some RG400/U at the next hamfest I attend, I will buy some and try it. I could then compare results. It would be interesting to do some actual tests of the electrical impact of bending coax at radii needed for 2.4 inch OD cores, either single or stacked. Possibly some type of TDR test could be done to see if any deformaty would impact performance of the coax used in chokes, over the HF ham bands. Again, thanks for sharing your insight and experience. 73, Bob Nobis - N7RJN [hidden email] > On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email]> wrote: > > Robert Nobis wrote: > > After reviewing specs from several manufacturers, the “recommended” minimum bend radius for RG303 and RG400 is essentially the same at 1.0 inches. > > Hi Robert, > > I have wrapped RG400 on a two stack of FT240 form factor toroids with never an issue, without any change in electrical characteristics I could measure. These were a little less than a half inch radius, something I would never try with 303 or 142. > > A one inch radius or two inch diameter winding, per the listings you have quoted, would hang loose on most forms. In effect this specifies the 303/142/400 cables useless for winding on toroid cores of any HF suitable size in use by hams, including even the monumental T500A series toroids. > > ***However,*** > > I respectfully suggest that the minimum bending radius that you see published for RG400 can be ignored for ham purposes at HF and low VHF, and common sense is better suited to the problem. IMHO the ANSI standard (ANSI/SCTE 39 2007) uses a crude method better suited to measuring metallic sheathed cables, and ignores testing the needed characteristics directly, simply to avoid testing cost and complexity. > > I also suggest that everyone carefully study the ANSI standard until it is clear what they are doing mechanically and see what they are actually measuring: > > http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007.pdf <http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007.pdf> > > The method of measuring is in section 4. They are looking for a limit of 1% surface deformity when bending. > > In the case of RG400 with .195 inch OD, that would be 2/1000 of an inch (yes, that's three zeros, two one thousandths of an inch) bending deformity at the surface of the teflon jacket, or half the thickness of an average human hair. > > Anyone who works with teflon knows that the teflon jacket on the outside of the bend will stretch and the teflon on the inside of the bend will bunch, due to the difference in the radius, and particularly due to it being a soft material with no constraint to its outside surface. And there is the problem of managing to measure the thickness of something soft like teflon so as not to compress the teflon 2 mils during the measurement of something with a curved surface. > > The teflon dielectric between the inside of the shield and the center conductor, all we care about, is confined by the double shield, which opposes the teflon's tendency to deform. Further, the difference in the radius is smaller inside the shield, dividing down the differential measured at the surface of the jacket. > > The 19 strand center conductor in RG400 will easily follow the teflon in multiple bendings. The solid center conductor versions (303,142) to a degree will remember their first bend and will apply that deformity in the second and later bends, accumulating deformity at that point in the cable unless the second bend is identical to the first. That is why you see "once" or "bend once" in some of the listings for RG303 and RG142. I have no argument with the "bend once" specification in the 303 and 142 listings. It's relates to the reason I use RG400. > > RG400 is the only coax listed for certified aircraft installations in a lot of aircraft service vendor's web pages. I find 142 mentioned a few times as being easier to fit with connectors. I have not seen 303 mentioned on an aircraft service vendor web page. > > 73, Guy K2AV > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Elecraft mailing list
On Mon,2/8/2016 2:52 PM, Mel Farrer via Elecraft wrote:
> Let's do some basic thinking. Mel, You need to study my tutorial. Common mode chokes are NOT inductors, they are parallel resonant circuits, and it is their resistive impedance at resonance that makes the choke effective. 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Guy Olinger K2AV
Hi Bob, et al,
Thank you all for your careful attention. I read it wrong, as several have pointed out overnight. I transposed that to a percentage in my memory after reading it. One of the reasons for referring people to the original material in these cases. Someone will get it right. That makes it two and a half hairs :>) Doesn't appear to change the argument. To me anyway the method is still a crude measurement instead of watching a wide frequency scan while bending the cable along with other performance specific measurements. I still would not use the solid center conductor versions (RG142/303) on a winding. 73, Guy K2AV On Tuesday, February 9, 2016, Robert Nobis <[hidden email]> wrote: > Hi Guy, > > I am not sure how you arrived at the “2/1000 of an inch” figure from the > ANSI spec? The spec actually says “A change in ovality from a given > sample’s initial measured value of 0.010 inches or more (> 0.010) > represents the point of non-acceptable bending performance.” > > > 73, > > > Bob Nobis - N7RJN > [hidden email] <javascript:_e(%7B%7D,'cvml','[hidden email]');> > > > On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email] > <javascript:_e(%7B%7D,'cvml','[hidden email]');>> wrote: > > > I also suggest that everyone carefully study the ANSI standard until it is > clear what they are doing mechanically and see what they are actually > measuring: > > http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007.pdf > > The method of measuring is in section 4. They are looking for a limit of > 1% surface deformity when bending. > > In the case of RG400 with .195 inch OD, that would be 2/1000 of an inch > (yes, that's three zeros, two one thousandths of an inch) bending deformity > at the surface of the teflon jacket, or half the thickness of an average > human hair. > > > > > > -- Sent via Gmail Mobile on my iPhone ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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I'm one of the other Bob's or Robert's........
Since the assembly of coax wound around a toroid doughnut style bobbin is typically not exposed to vibration, such as might exist in an airplane, boat or space vehicle, the use of a solid conductor coax such as RG-303 would not seem to be of concern. The more important point and my experience and as related by others, the use of coax which has foam dielectric in a tight radius bend has been proven or shown to be problematic. As to if the manufactures bending radius dimension is being violated, I find to be of little concern. After all, as a rule, hams are noted for pushing things to the limit and then some and getting buy with it. If hams choose to "stick to the rules 100% in all aspects of their stations"............I'd say 75% of the stuff we use and methods employed would put most of the station stuff in the trash. 73 Bob, K4TAX On 2/9/2016 8:45 AM, Guy Olinger K2AV wrote: > Hi Bob, et al, > > Thank you all for your careful attention. > > I read it wrong, as several have pointed out overnight. I transposed that > to a percentage in my memory after reading it. One of the reasons for > referring people to the original material in these cases. Someone will get > it right. > > That makes it two and a half hairs :>) Doesn't appear to change the > argument. To me anyway the method is still a crude measurement instead of > watching a wide frequency scan while bending the cable along with other > performance specific measurements. > > I still would not use the solid center conductor versions (RG142/303) on a > winding. > > 73, Guy K2AV > > On Tuesday, February 9, 2016, Robert Nobis <[hidden email]> wrote: > >> Hi Guy, >> >> I am not sure how you arrived at the “2/1000 of an inch” figure from the >> ANSI spec? The spec actually says “A change in ovality from a given >> sample’s initial measured value of 0.010 inches or more (> 0.010) >> represents the point of non-acceptable bending performance.” >> >> >> 73, >> >> >> Bob Nobis - N7RJN >> [hidden email] <javascript:_e(%7B%7D,'cvml','[hidden email]');> >> >> >> On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email] >> <javascript:_e(%7B%7D,'cvml','[hidden email]');>> wrote: >> >> >> I also suggest that everyone carefully study the ANSI standard until it is >> clear what they are doing mechanically and see what they are actually >> measuring: >> >> http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007.pdf >> >> The method of measuring is in section 4. They are looking for a limit of >> 1% surface deformity when bending. >> >> In the case of RG400 with .195 inch OD, that would be 2/1000 of an inch >> (yes, that's three zeros, two one thousandths of an inch) bending deformity >> at the surface of the teflon jacket, or half the thickness of an average >> human hair. >> >> >> >> >> >> ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Hi Bob McGraw,
I agree, except on one point: I’s say 90%, rather than 75%, of the stuff we use and methods employed would put most of the station stuff in the trash. 73, Bob Nobis - N7RJN [hidden email] > On Feb 9, 2016, at 08:01, Bob McGraw K4TAX <[hidden email]> wrote: > > I'm one of the other Bob's or Robert's........ > > Since the assembly of coax wound around a toroid doughnut style bobbin is typically not exposed to vibration, such as might exist in an airplane, boat or space vehicle, the use of a solid conductor coax such as RG-303 would not seem to be of concern. The more important point and my experience and as related by others, the use of coax which has foam dielectric in a tight radius bend has been proven or shown to be problematic. As to if the manufactures bending radius dimension is being violated, I find to be of little concern. > > After all, as a rule, hams are noted for pushing things to the limit and then some and getting buy with it. If hams choose to "stick to the rules 100% in all aspects of their stations"............I'd say 75% of the stuff we use and methods employed would put most of the station stuff in the trash. > > 73 > Bob, K4TAX > > > > > > On 2/9/2016 8:45 AM, Guy Olinger K2AV wrote: >> Hi Bob, et al, >> >> Thank you all for your careful attention. >> >> I read it wrong, as several have pointed out overnight. I transposed that >> to a percentage in my memory after reading it. One of the reasons for >> referring people to the original material in these cases. Someone will get >> it right. >> >> That makes it two and a half hairs :>) Doesn't appear to change the >> argument. To me anyway the method is still a crude measurement instead of >> watching a wide frequency scan while bending the cable along with other >> performance specific measurements. >> >> I still would not use the solid center conductor versions (RG142/303) on a >> winding. >> >> 73, Guy K2AV >> >> On Tuesday, February 9, 2016, Robert Nobis <[hidden email]> wrote: >> >>> Hi Guy, >>> >>> I am not sure how you arrived at the “2/1000 of an inch” figure from the >>> ANSI spec? The spec actually says “A change in ovality from a given >>> sample’s initial measured value of 0.010 inches or more (> 0.010) >>> represents the point of non-acceptable bending performance.” >>> >>> >>> 73, >>> >>> >>> Bob Nobis - N7RJN >>> [hidden email] <javascript:_e(%7B%7D,'cvml','[hidden email]');> >>> >>> >>> On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email] >>> <javascript:_e(%7B%7D,'cvml','[hidden email]');>> wrote: >>> >>> >>> I also suggest that everyone carefully study the ANSI standard until it is >>> clear what they are doing mechanically and see what they are actually >>> measuring: >>> >>> http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007.pdf >>> >>> The method of measuring is in section 4. They are looking for a limit of >>> 1% surface deformity when bending. >>> >>> In the case of RG400 with .195 inch OD, that would be 2/1000 of an inch >>> (yes, that's three zeros, two one thousandths of an inch) bending deformity >>> at the surface of the teflon jacket, or half the thickness of an average >>> human hair. >>> >>> >>> >>> >>> >>> > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Bob McGraw - K4TAX
Hello Bob,
The coax could be exposed to heat when in service as a balun, so I would respectfully disagree with you on this one point. If you exceed the bending radius of your coax, you stand a higher percentage chance of causing a shield to center connector short, (due to center conductor migration), than if you don't exceed the bend radius. When running high power, you also stand a better chance of heating up your core material, (and hence your coax), which makes it easier for the center conductor to migrate, and if you have exceeded the bend radius-- well-- we're pretty sure where it will migrate too... One has to pick one's fights so to speak, and I would not pick bending radius as one of my fights... If you lose, it is never good when the center conductor shorts to the shield at Kilowatt power levels. Use loops large enough to stay within the bending radius of your coax. Now if this is QRP, you could probably get away with it. -- 73's, and thanks, Dave For software/hardware reviews see: http://www.nk7z.net For MixW support see: https://groups.yahoo.com/neo/groups/mixw/info For SSTV help see: http://groups.yahoo.com/neo/groups/MM-SSTV/info On Tue, 2016-02-09 at 09:01 -0600, Bob McGraw K4TAX wrote: > I'm one of the other Bob's or Robert's........ > > Since the assembly of coax wound around a toroid doughnut style > bobbin > is typically not exposed to vibration, such as might exist in an > airplane, boat or space vehicle, the use of a solid conductor coax > such > as RG-303 would not seem to be of concern. The more important point > and > my experience and as related by others, the use of coax which has > foam > dielectric in a tight radius bend has been proven or shown to be > problematic. As to if the manufactures bending radius dimension > is > being violated, I find to be of little concern. > > After all, as a rule, hams are noted for pushing things to the limit > and > then some and getting buy with it. If hams choose to "stick to the > rules 100% in all aspects of their stations"............I'd say 75% > of > the stuff we use and methods employed would put most of the station > stuff in the trash. > > 73 > Bob, K4TAX > > > > > > On 2/9/2016 8:45 AM, Guy Olinger K2AV wrote: > > Hi Bob, et al, > > > > Thank you all for your careful attention. > > > > I read it wrong, as several have pointed out overnight. I > > transposed that > > to a percentage in my memory after reading it. One of the reasons > > for > > referring people to the original material in these cases. Someone > > will get > > it right. > > > > That makes it two and a half hairs :>) Doesn't appear to change > > the > > argument. To me anyway the method is still a crude measurement > > instead of > > watching a wide frequency scan while bending the cable along with > > other > > performance specific measurements. > > > > I still would not use the solid center conductor versions > > (RG142/303) on a > > winding. > > > > 73, Guy K2AV > > > > On Tuesday, February 9, 2016, Robert Nobis <[hidden email]> wrote: > > > > > Hi Guy, > > > > > > I am not sure how you arrived at the “2/1000 of an inch” figure > > > from the > > > ANSI spec? The spec actually says “A change in ovality from a > > > given > > > sample’s initial measured value of 0.010 inches or more (> 0.010) > > > represents the point of non-acceptable bending performance.” > > > > > > > > > 73, > > > > > > > > > Bob Nobis - N7RJN > > > [hidden email] <javascript:_e(%7B%7D,'cvml','[hidden email]');> > > > > > > > > > On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email] > > > <javascript:_e(%7B%7D,'cvml','[hidden email]');>> wrote: > > > > > > > > > I also suggest that everyone carefully study the ANSI standard > > > until it is > > > clear what they are doing mechanically and see what they are > > > actually > > > measuring: > > > > > > http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007 > > > > > > The method of measuring is in section 4. They are looking for a > > > limit of > > > 1% surface deformity when bending. > > > > > > In the case of RG400 with .195 inch OD, that would be 2/1000 of > > > an inch > > > (yes, that's three zeros, two one thousandths of an inch) bending > > > deformity > > > at the surface of the teflon jacket, or half the thickness of an > > > average > > > human hair. > > > > > > > > > > > > > > > > > > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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If one has heating issues to that magnitude, they have other more critical issues which should be addressed.
Bob, K4TAX Sent from my iPhone > On Feb 9, 2016, at 9:24 AM, Dave Cole <[hidden email]> wrote: > > Hello Bob, > > The coax could be exposed to heat when in service as a balun, so I > would respectfully disagree with you on this one point. > > If you exceed the bending radius of your coax, you stand a higher > percentage chance of causing a shield to center connector short, (due > to center conductor migration), than if you don't exceed the bend > radius. When running high power, you also stand a better chance of > heating up your core material, (and hence your coax), which makes it > easier for the center conductor to migrate, and if you have exceeded > the bend radius-- well-- we're pretty sure where it will migrate > too... > > One has to pick one's fights so to speak, and I would not pick bending > radius as one of my fights... > > If you lose, it is never good when the center conductor shorts to the > shield at Kilowatt power levels. Use loops large enough to stay within > the bending radius of your coax. Now if this is QRP, you could > probably get away with it. > > -- > 73's, and thanks, > Dave > > For software/hardware reviews see: > http://www.nk7z.net > > For MixW support see: > https://groups.yahoo.com/neo/groups/mixw/info > > For SSTV help see: > http://groups.yahoo.com/neo/groups/MM-SSTV/info > > > >> On Tue, 2016-02-09 at 09:01 -0600, Bob McGraw K4TAX wrote: >> I'm one of the other Bob's or Robert's........ >> >> Since the assembly of coax wound around a toroid doughnut style >> bobbin >> is typically not exposed to vibration, such as might exist in an >> airplane, boat or space vehicle, the use of a solid conductor coax >> such >> as RG-303 would not seem to be of concern. The more important point >> and >> my experience and as related by others, the use of coax which has >> foam >> dielectric in a tight radius bend has been proven or shown to be >> problematic. As to if the manufactures bending radius dimension >> is >> being violated, I find to be of little concern. >> >> After all, as a rule, hams are noted for pushing things to the limit >> and >> then some and getting buy with it. If hams choose to "stick to the >> rules 100% in all aspects of their stations"............I'd say 75% >> of >> the stuff we use and methods employed would put most of the station >> stuff in the trash. >> >> 73 >> Bob, K4TAX >> >> >> >> >> >>> On 2/9/2016 8:45 AM, Guy Olinger K2AV wrote: >>> Hi Bob, et al, >>> >>> Thank you all for your careful attention. >>> >>> I read it wrong, as several have pointed out overnight. I >>> transposed that >>> to a percentage in my memory after reading it. One of the reasons >>> for >>> referring people to the original material in these cases. Someone >>> will get >>> it right. >>> >>> That makes it two and a half hairs :>) Doesn't appear to change >>> the >>> argument. To me anyway the method is still a crude measurement >>> instead of >>> watching a wide frequency scan while bending the cable along with >>> other >>> performance specific measurements. >>> >>> I still would not use the solid center conductor versions >>> (RG142/303) on a >>> winding. >>> >>> 73, Guy K2AV >>> >>>> On Tuesday, February 9, 2016, Robert Nobis <[hidden email]> wrote: >>>> >>>> Hi Guy, >>>> >>>> I am not sure how you arrived at the “2/1000 of an inch” figure >>>> from the >>>> ANSI spec? The spec actually says “A change in ovality from a >>>> given >>>> sample’s initial measured value of 0.010 inches or more (> 0.010) >>>> represents the point of non-acceptable bending performance.” >>>> >>>> >>>> 73, >>>> >>>> >>>> Bob Nobis - N7RJN >>>> [hidden email] <javascript:_e(%7B%7D,'cvml','[hidden email]');> >>>> >>>> >>>> On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email] >>>> <javascript:_e(%7B%7D,'cvml','[hidden email]');>> wrote: >>>> >>>> >>>> I also suggest that everyone carefully study the ANSI standard >>>> until it is >>>> clear what they are doing mechanically and see what they are >>>> actually >>>> measuring: >>>> >>>> http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007 >>>> >>>> The method of measuring is in section 4. They are looking for a >>>> limit of >>>> 1% surface deformity when bending. >>>> >>>> In the case of RG400 with .195 inch OD, that would be 2/1000 of >>>> an inch >>>> (yes, that's three zeros, two one thousandths of an inch) bending >>>> deformity >>>> at the surface of the teflon jacket, or half the thickness of an >>>> average >>>> human hair. >> >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[hidden email] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to [hidden email] > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Robert Nobis - N7RJN
As of sometime yesterday, 02/08/2016, I was granted my Amateur Radio
License with General privileges. Thank you to everyone who had a hand in making this possible. I am quite happy and yes, a little proud, too. In just a few hours, I will take possession of my Elecraft K3s and P3 components. I have two super selfless, super-experienced, super-patient operators who've taken an interest in me. And I have TWO local clubs available to me from whose members I can learn and through which I can contribute to the hobby and my community. My cup truly runneth over... Thank you, Lord! 73, Clay, KG5LKV On 2/9/2016 9:06 AM, Robert Nobis wrote: > Hi Bob McGraw, > > I agree, except on one point: I’s say 90%, rather than 75%, of the stuff we use and methods employed would put most of the station stuff in the trash. > > 73, > > > Bob Nobis - N7RJN > [hidden email] > > >> On Feb 9, 2016, at 08:01, Bob McGraw K4TAX <[hidden email]> wrote: >> >> I'm one of the other Bob's or Robert's........ >> >> Since the assembly of coax wound around a toroid doughnut style bobbin is typically not exposed to vibration, such as might exist in an airplane, boat or space vehicle, the use of a solid conductor coax such as RG-303 would not seem to be of concern. The more important point and my experience and as related by others, the use of coax which has foam dielectric in a tight radius bend has been proven or shown to be problematic. As to if the manufactures bending radius dimension is being violated, I find to be of little concern. >> >> After all, as a rule, hams are noted for pushing things to the limit and then some and getting buy with it. If hams choose to "stick to the rules 100% in all aspects of their stations"............I'd say 75% of the stuff we use and methods employed would put most of the station stuff in the trash. >> >> 73 >> Bob, K4TAX >> >> >> >> >> >> On 2/9/2016 8:45 AM, Guy Olinger K2AV wrote: >>> Hi Bob, et al, >>> >>> Thank you all for your careful attention. >>> >>> I read it wrong, as several have pointed out overnight. I transposed that >>> to a percentage in my memory after reading it. One of the reasons for >>> referring people to the original material in these cases. Someone will get >>> it right. >>> >>> That makes it two and a half hairs :>) Doesn't appear to change the >>> argument. To me anyway the method is still a crude measurement instead of >>> watching a wide frequency scan while bending the cable along with other >>> performance specific measurements. >>> >>> I still would not use the solid center conductor versions (RG142/303) on a >>> winding. >>> >>> 73, Guy K2AV >>> >>> On Tuesday, February 9, 2016, Robert Nobis <[hidden email]> wrote: >>> >>>> Hi Guy, >>>> >>>> I am not sure how you arrived at the “2/1000 of an inch” figure from the >>>> ANSI spec? The spec actually says “A change in ovality from a given >>>> sample’s initial measured value of 0.010 inches or more (> 0.010) >>>> represents the point of non-acceptable bending performance.” >>>> >>>> >>>> 73, >>>> >>>> >>>> Bob Nobis - N7RJN >>>> [hidden email] <javascript:_e(%7B%7D,'cvml','[hidden email]');> >>>> >>>> >>>> On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email] >>>> <javascript:_e(%7B%7D,'cvml','[hidden email]');>> wrote: >>>> >>>> >>>> I also suggest that everyone carefully study the ANSI standard until it is >>>> clear what they are doing mechanically and see what they are actually >>>> measuring: >>>> >>>> http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007.pdf >>>> >>>> The method of measuring is in section 4. They are looking for a limit of >>>> 1% surface deformity when bending. >>>> >>>> In the case of RG400 with .195 inch OD, that would be 2/1000 of an inch >>>> (yes, that's three zeros, two one thousandths of an inch) bending deformity >>>> at the surface of the teflon jacket, or half the thickness of an average >>>> human hair. >>>> >>>> >>>> >>>> >>>> >>>> >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[hidden email] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to [hidden email] > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
Re: I am officially a HAM!!!
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Congratulations on all points.
Bob, K4TAX Sent from my iPhone > On Feb 9, 2016, at 9:57 AM, Clay Autery <[hidden email]> wrote: > > As of sometime yesterday, 02/08/2016, I was granted my Amateur Radio > License with General privileges. > > Thank you to everyone who had a hand in making this possible. I am > quite happy and yes, a little proud, too. > > In just a few hours, I will take possession of my Elecraft K3s and P3 > components. > I have two super selfless, super-experienced, super-patient operators > who've taken an interest in me. > And I have TWO local clubs available to me from whose members I can > learn and through which I can contribute to the hobby and my community. > > My cup truly runneth over... Thank you, Lord! > > 73, > Clay, KG5LKV > >> On 2/9/2016 9:06 AM, Robert Nobis wrote: >> Hi Bob McGraw, >> >> I agree, except on one point: I’s say 90%, rather than 75%, of the stuff we use and methods employed would put most of the station stuff in the trash. >> >> 73, >> >> >> Bob Nobis - N7RJN >> [hidden email] >> >> >>> On Feb 9, 2016, at 08:01, Bob McGraw K4TAX <[hidden email]> wrote: >>> >>> I'm one of the other Bob's or Robert's........ >>> >>> Since the assembly of coax wound around a toroid doughnut style bobbin is typically not exposed to vibration, such as might exist in an airplane, boat or space vehicle, the use of a solid conductor coax such as RG-303 would not seem to be of concern. The more important point and my experience and as related by others, the use of coax which has foam dielectric in a tight radius bend has been proven or shown to be problematic. As to if the manufactures bending radius dimension is being violated, I find to be of little concern. >>> >>> After all, as a rule, hams are noted for pushing things to the limit and then some and getting buy with it. If hams choose to "stick to the rules 100% in all aspects of their stations"............I'd say 75% of the stuff we use and methods employed would put most of the station stuff in the trash. >>> >>> 73 >>> Bob, K4TAX >>> >>> >>> >>> >>> >>>> On 2/9/2016 8:45 AM, Guy Olinger K2AV wrote: >>>> Hi Bob, et al, >>>> >>>> Thank you all for your careful attention. >>>> >>>> I read it wrong, as several have pointed out overnight. I transposed that >>>> to a percentage in my memory after reading it. One of the reasons for >>>> referring people to the original material in these cases. Someone will get >>>> it right. >>>> >>>> That makes it two and a half hairs :>) Doesn't appear to change the >>>> argument. To me anyway the method is still a crude measurement instead of >>>> watching a wide frequency scan while bending the cable along with other >>>> performance specific measurements. >>>> >>>> I still would not use the solid center conductor versions (RG142/303) on a >>>> winding. >>>> >>>> 73, Guy K2AV >>>> >>>>> On Tuesday, February 9, 2016, Robert Nobis <[hidden email]> wrote: >>>>> >>>>> Hi Guy, >>>>> >>>>> I am not sure how you arrived at the “2/1000 of an inch” figure from the >>>>> ANSI spec? The spec actually says “A change in ovality from a given >>>>> sample’s initial measured value of 0.010 inches or more (> 0.010) >>>>> represents the point of non-acceptable bending performance.” >>>>> >>>>> >>>>> 73, >>>>> >>>>> >>>>> Bob Nobis - N7RJN >>>>> [hidden email] <javascript:_e(%7B%7D,'cvml','[hidden email]');> >>>>> >>>>> >>>>> On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email] >>>>> <javascript:_e(%7B%7D,'cvml','[hidden email]');>> wrote: >>>>> >>>>> >>>>> I also suggest that everyone carefully study the ANSI standard until it is >>>>> clear what they are doing mechanically and see what they are actually >>>>> measuring: >>>>> >>>>> http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007.pdf >>>>> >>>>> The method of measuring is in section 4. They are looking for a limit of >>>>> 1% surface deformity when bending. >>>>> >>>>> In the case of RG400 with .195 inch OD, that would be 2/1000 of an inch >>>>> (yes, that's three zeros, two one thousandths of an inch) bending deformity >>>>> at the surface of the teflon jacket, or half the thickness of an average >>>>> human hair. >>> >>> ______________________________________________________________ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:[hidden email] >>> >>> This list hosted by: http://www.qsl.net >>> Please help support this email list: http://www.qsl.net/donate.html >>> Message delivered to [hidden email] >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[hidden email] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to [hidden email] > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Clay Autery
Congratulations Clay! You have picked a very good radio, and a very
good hobby as well... Have fun, and welcome, hope to work you soon! -- 73's, and thanks, Dave For software/hardware reviews see: http://www.nk7z.net For MixW support see: https://groups.yahoo.com/neo/groups/mixw/info For SSTV help see: http://groups.yahoo.com/neo/groups/MM-SSTV/info On Tue, 2016-02-09 at 09:57 -0600, Clay Autery wrote: > As of sometime yesterday, 02/08/2016, I was granted my Amateur Radio > License with General privileges. > > Thank you to everyone who had a hand in making this possible. I am > quite happy and yes, a little proud, too. > > In just a few hours, I will take possession of my Elecraft K3s and P3 > components. > I have two super selfless, super-experienced, super-patient operators > who've taken an interest in me. > And I have TWO local clubs available to me from whose members I can > learn and through which I can contribute to the hobby and my > community. > > My cup truly runneth over... Thank you, Lord! > > 73, > Clay, KG5LKV > > On 2/9/2016 9:06 AM, Robert Nobis wrote: > > Hi Bob McGraw, > > > > I agree, except on one point: I’s say 90%, rather than 75%, of the > > stuff we use and methods employed would put most of the station > > stuff in the trash. > > > > 73, > > > > > > Bob Nobis - N7RJN > > [hidden email] > > > > > > > On Feb 9, 2016, at 08:01, Bob McGraw K4TAX <[hidden email]> > > > wrote: > > > > > > I'm one of the other Bob's or Robert's........ > > > > > > Since the assembly of coax wound around a toroid doughnut style > > > bobbin is typically not exposed to vibration, such as might exist > > > in an airplane, boat or space vehicle, the use of a solid > > > conductor coax such as RG-303 would not seem to be of > > > concern. The more important point and my experience and as > > > related by others, the use of coax which has foam dielectric in a > > > tight radius bend has been proven or shown to be > > > problematic. As to if the manufactures bending radius > > > dimension is being violated, I find to be of little concern. > > > > > > After all, as a rule, hams are noted for pushing things to the > > > limit and then some and getting buy with it. If hams choose to > > > "stick to the rules 100% in all aspects of their > > > stations"............I'd say 75% of the stuff we use and methods > > > employed would put most of the station stuff in the trash. > > > > > > 73 > > > Bob, K4TAX > > > > > > > > > > > > > > > > > > On 2/9/2016 8:45 AM, Guy Olinger K2AV wrote: > > > > Hi Bob, et al, > > > > > > > > Thank you all for your careful attention. > > > > > > > > I read it wrong, as several have pointed out overnight. I > > > > transposed that > > > > to a percentage in my memory after reading it. One of the > > > > reasons for > > > > referring people to the original material in these cases. > > > > Someone will get > > > > it right. > > > > > > > > That makes it two and a half hairs :>) Doesn't appear to > > > > change the > > > > argument. To me anyway the method is still a crude measurement > > > > instead of > > > > watching a wide frequency scan while bending the cable along > > > > with other > > > > performance specific measurements. > > > > > > > > I still would not use the solid center conductor versions > > > > (RG142/303) on a > > > > winding. > > > > > > > > 73, Guy K2AV > > > > > > > > On Tuesday, February 9, 2016, Robert Nobis <[hidden email]> > > > > wrote: > > > > > > > > > Hi Guy, > > > > > > > > > > I am not sure how you arrived at the “2/1000 of an inch” > > > > > figure from the > > > > > ANSI spec? The spec actually says “A change in ovality from a > > > > > given > > > > > sample’s initial measured value of 0.010 inches or more (> > > > > > 0.010) > > > > > represents the point of non-acceptable bending performance.” > > > > > > > > > > > > > > > 73, > > > > > > > > > > > > > > > Bob Nobis - N7RJN > > > > > [hidden email] <javascript:_e(%7B%7D,'cvml','[hidden email] > > > > > ');> > > > > > > > > > > > > > > > On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email] > > > > > m > > > > > <javascript:_e(%7B%7D,'cvml','[hidden email]');>> wrote: > > > > > > > > > > > > > > > I also suggest that everyone carefully study the ANSI > > > > > standard until it is > > > > > clear what they are doing mechanically and see what they are > > > > > actually > > > > > measuring: > > > > > > > > > > http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%20 > > > > > 2007.pdf > > > > > > > > > > The method of measuring is in section 4. They are looking for > > > > > a limit of > > > > > 1% surface deformity when bending. > > > > > > > > > > In the case of RG400 with .195 inch OD, that would be 2/1000 > > > > > of an inch > > > > > (yes, that's three zeros, two one thousandths of an inch) > > > > > bending deformity > > > > > at the surface of the teflon jacket, or half the thickness of > > > > > an average > > > > > human hair. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > ______________________________________________________________ > > > Elecraft mailing list > > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > > Help: http://mailman.qth.net/mmfaq.htm > > > Post: mailto:[hidden email] > > > > > > This list hosted by: http://www.qsl.net > > > Please help support this email list: http://www.qsl.net/donate.ht > > > ml > > > Message delivered to [hidden email] > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:[hidden email] > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > Message delivered to [hidden email] > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Clay Autery
Congrats Clay!!
I remember getting my ticket in the PO box in September, 1951. I owe virtually everything in my life to the hobby! 73 Ken Kopp - K0PP [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
Re: [Bulk] I am officially a HAM!!!
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In reply to this post by Clay Autery
Welcome aboard, Clay! Congratulations on your achievement
Tom , WB2QDG K2 #1103 On 2/9/2016 10:57 AM, Clay Autery wrote: > As of sometime yesterday, 02/08/2016, I was granted my Amateur Radio > License with General privileges. > > Thank you to everyone who had a hand in making this possible. I am > quite happy and yes, a little proud, too. > > In just a few hours, I will take possession of my Elecraft K3s and P3 > components. > I have two super selfless, super-experienced, super-patient operators > who've taken an interest in me. > And I have TWO local clubs available to me from whose members I can > learn and through which I can contribute to the hobby and my community. > > My cup truly runneth over... Thank you, Lord! > > 73, > Clay, KG5LKV > > On 2/9/2016 9:06 AM, Robert Nobis wrote: >> Hi Bob McGraw, >> >> I agree, except on one point: I’s say 90%, rather than 75%, of the stuff we use and methods employed would put most of the station stuff in the trash. >> >> 73, >> >> >> Bob Nobis - N7RJN >> [hidden email] >> >> >>> On Feb 9, 2016, at 08:01, Bob McGraw K4TAX <[hidden email]> wrote: >>> >>> I'm one of the other Bob's or Robert's........ >>> >>> Since the assembly of coax wound around a toroid doughnut style bobbin is typically not exposed to vibration, such as might exist in an airplane, boat or space vehicle, the use of a solid conductor coax such as RG-303 would not seem to be of concern. The more important point and my experience and as related by others, the use of coax which has foam dielectric in a tight radius bend has been proven or shown to be problematic. As to if the manufactures bending radius dimension is being violated, I find to be of little concern. >>> >>> After all, as a rule, hams are noted for pushing things to the limit and then some and getting buy with it. If hams choose to "stick to the rules 100% in all aspects of their stations"............I'd say 75% of the stuff we use and methods employed would put most of the station stuff in the trash. >>> >>> 73 >>> Bob, K4TAX >>> >>> >>> >>> >>> >>> On 2/9/2016 8:45 AM, Guy Olinger K2AV wrote: >>>> Hi Bob, et al, >>>> >>>> Thank you all for your careful attention. >>>> >>>> I read it wrong, as several have pointed out overnight. I transposed that >>>> to a percentage in my memory after reading it. One of the reasons for >>>> referring people to the original material in these cases. Someone will get >>>> it right. >>>> >>>> That makes it two and a half hairs :>) Doesn't appear to change the >>>> argument. To me anyway the method is still a crude measurement instead of >>>> watching a wide frequency scan while bending the cable along with other >>>> performance specific measurements. >>>> >>>> I still would not use the solid center conductor versions (RG142/303) on a >>>> winding. >>>> >>>> 73, Guy K2AV >>>> >>>> On Tuesday, February 9, 2016, Robert Nobis <[hidden email]> wrote: >>>> >>>>> Hi Guy, >>>>> >>>>> I am not sure how you arrived at the “2/1000 of an inch” figure from the >>>>> ANSI spec? The spec actually says “A change in ovality from a given >>>>> sample’s initial measured value of 0.010 inches or more (> 0.010) >>>>> represents the point of non-acceptable bending performance.” >>>>> >>>>> >>>>> 73, >>>>> >>>>> >>>>> Bob Nobis - N7RJN >>>>> [hidden email] <javascript:_e(%7B%7D,'cvml','[hidden email]');> >>>>> >>>>> >>>>> On Feb 8, 2016, at 18:01, Guy Olinger K2AV <[hidden email] >>>>> <javascript:_e(%7B%7D,'cvml','[hidden email]');>> wrote: >>>>> >>>>> >>>>> I also suggest that everyone carefully study the ANSI standard until it is >>>>> clear what they are doing mechanically and see what they are actually >>>>> measuring: >>>>> >>>>> http://www.scte.org/documents/pdf/standards/ANSI_SCTE%2039%202007.pdf >>>>> >>>>> The method of measuring is in section 4. They are looking for a limit of >>>>> 1% surface deformity when bending. >>>>> >>>>> In the case of RG400 with .195 inch OD, that would be 2/1000 of an inch >>>>> (yes, that's three zeros, two one thousandths of an inch) bending deformity >>>>> at the surface of the teflon jacket, or half the thickness of an average >>>>> human hair. >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>> ______________________________________________________________ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:[hidden email] >>> >>> This list hosted by: http://www.qsl.net >>> Please help support this email list: http://www.qsl.net/donate.html >>> Message delivered to [hidden email] >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[hidden email] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to [hidden email] > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] -- In democracy it’s your vote that counts; In feudalism it’s your count that votes. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Jim Allen
I have addressed this by showing photographs of winding techniques for
coax normally used for transmitting, and for short lengths of transmission line formed by taping together a pair of 4-6 ft of #12 THHN. There's also text that goes with it, noting that winding radius should follow mfr recommendations for bending radius, that close spacing should be used to lower the resonant frequency and wider spacing to raise it. Note also that the dielectric constant of outer jacket material can have a quite significant effect on the bandwidth of ferrite chokes. For example, the bandwidth of those THHN chokes is MUCH greater than chokes would with typical RG8, RG213, RG11. Years ago, someone sent me a length of one of the teflon coaxes and I measured some chokes. As I recall, their bandwidth was lower than those wound with conventional coax. 73, Jim K9YC 73, Jim K9YC On Tue,2/9/2016 7:45 AM, James Robbins wrote: > > Good morning Jim, > > I am wondering if you could opine about how “tightly” coax needs to be > wound around a torroid for balun use (or other uses, for that matter)? > > In other words, while there have been so many Elecraft postings about > the bending radii of various types of coax, there is no information > posted about how tightly (closely) the coax needs to be wound around > the edge of the toroid. (When I have wound small torroids with magnet > wire, the winding is tight against the core. I’m not sure this is > even possible, let alone needed, for a balun.) > > If this is in one of your “papers”, please just refer me to the paper > and I’ll dig it out. > > 73, > > Jim Robbins > > N1JR > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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