Noise Problems...still
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Hi everyone,
Well, the noise level has been lowered a lot, but I'm still getting higher noise levels than I think I should. On 40-meters, I am getting an average of S2-4 peaking at S5 around the time thunderstorms begin to form. I've put up a vertical which helped. Putting down 12 tuned radials, 2 for each band, helped even more. Moving the power supply a few feet away may have also made a difference but I can't tell by ear. I am using the standard red/black zip type supply line from the power supply to the radio. I am wondering if going to coax to supply power to the radio may not drop the noise level even more? I would think that the R/C tank in the radios power circuit would take any ripple or noise out but maybe I'm wrong. I also have a ground that is a 20' long piece of 10GA bare copper wire running to a single lightning rod from a second story window. I'm now wondering if this wire isn't acting like part of the antenna or maybe injecting my transmitted signal back into the receiver via the power supply. Since I'm only running 5-10 watts output, should I use coax for the ground as well and decouple it with ferrite beads just in case? For a beginner, this is all pretty confusing! I read so much, trying to come up to speed quickly. The problem is that I begin confusing which solution goes to what problem I remember reading about last month in some periodical can't remember. Sometimes a little brain damage helps 73 de Terry - KC0QZX _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: Noise Problems...still
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S2 - S4 with only about S5 before a thunderstorm? I think that's pretty
good, Terry. Last night, just monitoring 40 Meters while puttering around in the shack, I had an S2 - S3 level. It would get worse from time to time. I think somebody in the neighborhood had an air conditioner compressor giving off some RF hash. 73 de Larry W2LJ ----- Original Message ----- From: <[hidden email]> To: "W2LJ" <[hidden email]> Cc: "Elecraft Discussion List" <[hidden email]> Sent: Sunday, August 01, 2004 12:17 PM Subject: [Elecraft] Noise Problems...still > Hi everyone, > > Well, the noise level has been lowered a lot, but I'm still getting > higher noise levels than I think I should. On 40-meters, I am getting an average > of S2-4 peaking at S5 around the time thunderstorms begin to form. > > I've put up a vertical which helped. Putting down 12 tuned radials, 2 for > each band, helped even more. Moving the power supply a few feet away may have > also made a difference but I can't tell by ear. > > I am using the standard red/black zip type supply line from the power supply > to the radio. I am wondering if going to coax to supply power to the radio > may not drop the noise level even more? I would think that the R/C tank in the > radios power circuit would take any ripple or noise out but maybe I'm wrong. > > I also have a ground that is a 20' long piece of 10GA bare copper wire > running to a single lightning rod from a second story window. I'm now wondering if > this wire isn't acting like part of the antenna or maybe injecting my > transmitted signal back into the receiver via the power supply. Since I'm only > running 5-10 watts output, should I use coax for the ground as well and decouple it > with ferrite beads just in case? > > For a beginner, this is all pretty confusing! I read so much, trying to come > up to speed quickly. The problem is that I begin confusing which solution > goes to what problem I remember reading about last month in some periodical > can't remember. > > Sometimes a little brain damage helps > > 73 de Terry - KC0QZX > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Wingkeel
Terry,
It does sound like you are making good progress. Take things one step at a time and you will get up to speed - don't try to rush it. Are your tuned radials right on the ground? If they are, the proximity to ground will de-tune them negating all your hard work!!! If you can elevate them to about 7 ft (above head height), then tuned radials are a good thing, but if they are right on the ground the length is not critical - on the ground you are just trying to produce a good conductive ground screen out from the base of the antenna, so any length about 1/4 wave or more for the lowest band will do. If the radials are elevated, it is important that they be tuned in relationship to the vertical element for each band. Relating your ground system to noise pickup may be like comparing apples and oranges. It just might be that the ambient noise level at your location is high and you will have to work around it. If you have a high noise level, your antenna proper may be picking it up and no amount of decoupling will decrease it. There are techniques for cancelling out noise pickup by phasing methods, but adjustments are usually quite 'touchy' and require a separate noise pickup antenna - you may have to resort to similar techniques in the end, but get your main antenna system in shape first. As an entirely different matter, your station ground system (20 ft long copper wire) is just fine for DC and some small measure of lightning protection, BUT it may not be providing you with a good RF ground. Usually the poor RF ground at the shack will show up as some RF in the shack (metallic things 'bite' you when you are transmitting or you will get some strange feedback 'happenings'). You can add to your ground system with just some wire - a piece 1/4 wavelength long at each band you will operate. Connect the near end to your station ground and run the far ends anywhere you can. If you need to run them in parallel, separate the ends by at least a foot. NOTE WELL - there may be high RF voltage on the far ends of these wires, so insulate them just as you would for an antenna end and keep them out of reach of others who might walk near them. It is good to run them straight, but not necessary, but don't make any sharp bends (use a long radius if you must turn them). These wires have a high RF impedance at the far end and a low RF impedance (ideally zero) at the shack end due to the voltage/current transformation of a 1/4 wavelength wire. Try it and see if it helps - it certainly can't hurt anything. 73, Don W3FPR ----- Original Message ----- > > Well, the noise level has been lowered a lot, but I'm still getting > higher noise levels than I think I should. On 40-meters, I am getting an average > of S2-4 peaking at S5 around the time thunderstorms begin to form. > > I've put up a vertical which helped. Putting down 12 tuned radials, 2 for > each band, helped even more. Moving the power supply a few feet away may have > also made a difference but I can't tell by ear. > > I am using the standard red/black zip type supply line from the power supply > to the radio. I am wondering if going to coax to supply power to the radio > may not drop the noise level even more? I would think that the R/C tank in the > radios power circuit would take any ripple or noise out but maybe I'm wrong. > > I also have a ground that is a 20' long piece of 10GA bare copper wire > running to a single lightning rod from a second story window. I'm now wondering if > this wire isn't acting like part of the antenna or maybe injecting my > transmitted signal back into the receiver via the power supply. Since I'm only > running 5-10 watts output, should I use coax for the ground as well and decouple it > with ferrite beads just in case? > > For a beginner, this is all pretty confusing! I read so much, trying to come > up to speed quickly. The problem is that I begin confusing which solution > goes to what problem I remember reading about last month in some periodical > can't remember. > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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> > Well, the noise level has been lowered a lot, but I'm still getting > > higher noise levels than I think I should. On 40-meters, I am getting an > average > > of S2-4 peaking at S5 around the time thunderstorms begin to form. I wish that I only had S2-S4 noise on 40!!! If you put your RF gain knob to use, that should be no problem at all. How about a loop or beverage RX antenna? Although it's rarely discussed, many top notch stations swear by RX antennas for 40... RE: elevated radials; I've been messing with EZNEC models of both elevated and ground mounted radials. Unless they're really high (unpractically high, 1/4wl) they always show a bit less performance than a good normal ground mounted system (at least 32, 0.2 to 0.4 WL long). Neither method is going to have much to do with the amount of noise recieved. A dummy load is a very low noise antenna though :-) Perhaps a reflector like towertalk or antennaware could shed more light on your situation. 73, Blake N4GI _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Wingkeel
G'day,
| higher noise levels than I think I should. On 40-meters, I am getting an average | of S2-4 peaking at S5 around the time thunderstorms begin to form. What happens when the antenna is unplugged? S2-4 on 40 metres, presumably at night time, doesn't sound particularly unusual to me. That 20 foot "ground" is only "ground" at near DC. Your vertical, whilst not being balanced is the full two terminal antenna and doesn't need a "ground" at the radio to make it work. Regards, Mike VP8NO _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Wingkeel
Hi Terry:
>Well, the noise level has been lowered a lot, but I'm still getting >higher noise levels than I think I should. On 40-meters, I am getting an >average of S2-4 peaking at S5 around the time thunderstorms begin to form. Can I have your weather, please? Out here in the midwest (MO), it's not at all unusual for me to have S9+ noise during the summer months when thunderstoams are still quite some disstance away. I'd KILL for ONLY S2-S4 atmospheric noise on 40M!!! >I've put up a vertical which helped. Putting down 12 tuned radials, 2 for >each band, helped even more. Unfortunately, as soon as you 'put them down' on the ground, they're no longer 'tuned', but they will still work WELL! SO don't sweat it one bit. >Moving the power supply a few feet away may have also made a difference >but I can't tell by ear. Probably only if it had a sizeable electro-magnetic field which might have been 'modulating' the K2's PLL... which is generally doubtful, bot not totally out of the question. >I am using the standard red/black zip type supply line from the power >supply to the radio. I am wondering if going to coax to supply power to >the radio may not drop the noise level even more? I would think that the >R/C tank in the radios power circuit would take any ripple or noise out >but maybe I'm wrong. Going to coax INSIDE THE HOUSE, will probably not be worth the added effort. 90%-95% chance whatever noise you're hearing is NOT being generated IN the house... and whatever might be, probably won't be filtered out by using COAX. >I also have a ground that is a 20' long piece of 10GA bare copper wire >running to a single lightning rod from a second story window. I'm now >wondering if this wire isn't acting like part of the antenna or maybe >injecting my transmitted signal back into the receiver via the power >supply. Since I'm only running 5-10 watts output, should I use coax for >the ground as well and decouple it with ferrite beads just in case? Actually, the ground you have is probably NOT being very helpful with regard to acting as an RF ground. But it might be helping a bit as an AC ground. It's probably long enough that it has more than ample reactance at HF to make it appear as a high impedance (e.g. not an RF ground). If you feel you need it for RF purposes (counterpoise or RF ground), you might want to consider 'tuning' it with something like the MFJ-931 'Artificial Ground': http://www.mfjenterprises.com/products.php?prodid=MFJ-931 This is one of the few MFJ products which I feel works as advertised, and decently well, too. But, it is a 'specialty' device, and I'd recommend it ONLY if you need it for providing an RF ground from the 2nd floor. It will probably NOT help get rid of any noise you might be receiving. Such a device can be built for wuite a bit less than the $90 they're asking for it... takes a small tuning capacitor, an inductor, a meter, and a SMALL handful of additional parts... might not look as pretty but it'd be functional. Making it 'purty' comes AFTER you make it work. >For a beginner, this is all pretty confusing! I read so much, trying to >come up to speed quickly. The problem is that I begin confusing which >solution goes to what problem I remember reading about last month in some >periodical can't remember. You're a General Class amateur, try using 20 meters during the day and early evening, rather than 40M. 20M (actually any band higher in frequency than 40M) will be lower in atmospheric noise, and my produce better listening conditions. During the summer, 40M and 80M generally are pretty noisy, due to more or less local storms... being in CO doesn't help your case much, as I've seen how readily those storms can kick up out there (here too!). There's NOTHING(!!!!) you can do about this, other than go to a higher frequency band and hope it's open to somewhere. As you get closer to Fall, the atmospheric conditions will moderate and 40/80M will again become much more productive... and quiet... but right now, you can't fight Mother Nature... so go with the flow, take your lumps and find a quieter band, if you can. 73, Tom Hammond N0SS _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Mike Harris-9
I'm glad to announce that K2 number 4334 (unbuilt number 2591 upgraded) is
finished and it is working very fine. It is completed with KIO2, K160RX, KAF2, KAT2, KNB2, KBT2, KSB2 and MH2 and it took about 53 hours to be completely builded, coarse aligned and fine aligned (I'm not fast, I know...): about 35 hours for the basic rig and 18 hours for the accessories and fine alignement. The only issue found was that I had to add 68pF and 100pF in parallel with C174 and C173 to have the correct BFO range (4916.77 KHz - 4912.59 KHz) but I think that it is still not enough to calibrate the narrow filters for RTTY using high tones, more about this on a next message.... Very minor-minor issue: I found that KIO2 needs a true RS232C signal with negative space, it did not work with a 0-8V signal and I had to slight modify my optocoupled CAT interface (I will publish the schematic diagram soon...). Sadly, the rig is not mine but it will go to his home, at iz2ftr, and it will make a pair with his K1 #1161 I think that, probably, this winter I will build one also for me and it will stay near his small brother, my K1 #1096, now ready for its third summer holidays... :-) In my city, Brescia, we have now five K1's and two K2's: the family is growing up! If you want to see some photos (iz2ftr's rigs are still to be added): http://www.hamlan.org/elecraftbs/photos.htm Ciao and 73 Guido, ik2bcp _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Can't calibrate K2 narrow RTTY filters to 2.2KHz (high tones)
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As I wrote in my last message, on K2 #4334 I was not able to calibrate the
narrow filters on RTTY normal to center high tones (about 2.2KHz): I reach about 1.6KHz and then the BFO resets to the intial frequency. It happened only on RTTY normal (LSB), on RTTY reverse (USB) I was able to calibrate correctly the filters to match the 2125/2295Hz tones. During the BFO calibration, I had to add 68pF and 100pF in parallel with C174 and C173 to have the correct BFO range (4916.77 KHz - 4912.59 KHz), do you think that I can't calibrate the filters because the BFO limits are not yet enough (too high or too low)? Any suggestion? Thanks and 73 Ciao Guido, ik2bcp _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: Can't calibrate K2 narrow RTTY filters to 2.2KHz (hightones)
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Guido,
The BFO RANGE is not sufficient to set the BFO far enough from the carrier and permit a tone of 2295 Hz on both sidebands. You will need a minimum range of 4590 Hz (and likely at least 500 Hz more will be required for a comfortable margin). Your range is only 4180 Hz. You could try increasing the BFO range or reset all the RTTY BFOs to center the filters at 1125/1295 rather than 2125/2295. This will require tuning the RTTY signal offset by 1 kHz and most sound card programs will properly handle that - if you are using a hardware TNC that requires the 'real' 2125/2295 audio tones, you will have to increase the BFO range further. 73, Don W3FPR ----- Original Message ----- > As I wrote in my last message, on K2 #4334 I was not able to calibrate the > narrow filters on RTTY normal to center high tones (about 2.2KHz): I reach > about 1.6KHz and then the BFO resets to the intial frequency. > It happened only on RTTY normal (LSB), on RTTY reverse (USB) I was able to > calibrate correctly the filters to match the 2125/2295Hz tones. > During the BFO calibration, I had to add 68pF and 100pF in parallel with > C174 and C173 to have the correct BFO range (4916.77 KHz - 4912.59 KHz), do > you think that I can't calibrate the filters because the BFO limits are not > yet enough (too high or too low)? > Any suggestion? _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Guido Tedeschi
On Aug 1, 2004, at 1:33 PM, Guido Tedeschi wrote: > If you want to see some photos (iz2ftr's rigs are still to be added): > http://www.hamlan.org/elecraftbs/photos.htm Hi Guido, Would you like to describe your "QRP Power Pack" featured in the photos? Thanks & 73, Doug N7BNT _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
QRP Power Pack for K1 (was Re: K2 #4334 alive and well!)
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Hi Doug,
the "QRP Power Pack" is the perfect little companion for my K1. It contains a 12V/1.3Ah gel battery and a voltage/current limited charger with a DC-DC converter to charge the battery with only a 12V source. When 12V is supplied to the input jack, the battery is charged and the output is directly connected to the input with a small relay, when no power is applied to the input jack, the relay switch the output to the battery. If it can be interesting, I will publish the schematic diagram on the web... Ciao and 73 Guido, ik2bcp ----- Original Message ----- From: "Doug Forman" <[hidden email]> To: "Guido Tedeschi" <[hidden email]> Cc: "Elecraft Discussion List" <[hidden email]> Sent: Monday, August 02, 2004 3:04 AM Subject: Re: [Elecraft] K2 #4334 alive and well! > > On Aug 1, 2004, at 1:33 PM, Guido Tedeschi wrote: > > > If you want to see some photos (iz2ftr's rigs are still to be added): > > http://www.hamlan.org/elecraftbs/photos.htm > > Hi Guido, > > Would you like to describe your "QRP Power Pack" featured in the photos? > > Thanks & 73, > > Doug N7BNT > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: QRP Power Pack for K1 (was Re: K2 #4334 alive and well!)
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On Tue, 3 Aug 2004, Guido Tedeschi wrote:
> Hi Doug, > the "QRP Power Pack" is the perfect little companion for my K1. > It contains a 12V/1.3Ah gel battery and a voltage/current limited charger > with a DC-DC converter to charge the battery with only a 12V source. > If it can be interesting, I will publish the schematic diagram on the web... I'd like to see it...thanks Thom http://www.baltimorehon.com/ Home of the Baltimore Lexicon http://www.tlchost.net/ Web Hosting as low as 3.49/month _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: QRP Power Pack for K1 (was Re: K2 #4334 alive and well!)
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In reply to this post by Guido Tedeschi
Thanks Guido... yes, I would like to see the schematic if you would
like to post it. Very nice work! From your photos, it looks like you have a fun group of Elecraft owners there! 73's Doug On Aug 3, 2004, at 12:56 PM, Guido Tedeschi wrote: > Hi Doug, > the "QRP Power Pack" is the perfect little companion for my K1. > It contains a 12V/1.3Ah gel battery and a voltage/current limited > charger > with a DC-DC converter to charge the battery with only a 12V source. > When 12V is supplied to the input jack, the battery is charged and the > output is directly connected to the input with a small relay, when no > power > is applied to the input jack, the relay switch the output to the > battery. > If it can be interesting, I will publish the schematic diagram on the > web... > Ciao and 73 > Guido, ik2bcp > > > ----- Original Message ----- > From: "Doug Forman" <[hidden email]> > To: "Guido Tedeschi" <[hidden email]> > Cc: "Elecraft Discussion List" <[hidden email]> > Sent: Monday, August 02, 2004 3:04 AM > Subject: Re: [Elecraft] K2 #4334 alive and well! > > >> >> On Aug 1, 2004, at 1:33 PM, Guido Tedeschi wrote: >> >>> If you want to see some photos (iz2ftr's rigs are still to be added): >>> http://www.hamlan.org/elecraftbs/photos.htm >> >> Hi Guido, >> >> Would you like to describe your "QRP Power Pack" featured in the >> photos? >> >> Thanks & 73, >> >> Doug N7BNT >> > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
QRP 12V Power Pack project is published...
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As promised to many of you, I published the project of the 12V Power Pack,
you can find it at this link: http://www.hamlan.org/tech/powerpack/qrppowerpack.htm I've done it in a hurry and I'm sorry for the short text and my bad english... :-( I hope you enjoy it Ciao and 73 Guido, ik2bcp _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Is anyone else getting duplicates of every email to the list?
_______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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