The use of a doublet
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Great post Rick!
Yes, the doublet has been over the years for me the easiest and best performing all band single antenna I've ever had. I feed mine with 450 also, but the top is only 135' long. I use the more robust SGC auto-tuner in external config. 40 feet of good quality coax and a high quality balun feed the tuner. With 20 watts applied, it finds best match in 3 seconds. It makes me feel like I'm cheating!! ;^D Duane N1BBR Hello Jim, I saw two of those tape measures once and they were actually part of a military dipole antenna system. The original antenna had 2 of them and you just pulled them ou to the coresponding frequency measurements on each side and you had a resonant dipole for that frequency. So if your friend used that to measue the wire with, then its most likely somewhere around 33 feet on each side. Being fed with 300 ohm balanced feedline makes your antenna a doublet - and a doublet is a very good all band antenna ! I use a doublet here that is 178 feet long - 89 feet per side and fed with 450 ohm feedline and it works 10 thru 160 meters via the tuner. 73 - Rick McKee, KC8AON Southern Ohio - EM88sn www.angelfire.com/electronic2/qrp With God all things are possible ~ ><(('> ~ -- [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 |
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DX Engineering shared an antenna with me that I put up and it works wonderful on all bands with a tuner. 120 ft and fed with 90 ft of 300 ohm line into a 1:1 balun of theirs and into the tuner with RE 213. Tuner is a Palstar AT2K. The feed line length must be 90 feet. YES, it really works. Phil Philip LaMarche LaMarche Enterprises, Inc. www.instantgourmetspices.com www.w9dvm.com 800-395-7795 pin 02 727-944-3226 FAX 727-937-8834 NASFT 30210 K3 #1605 CCA 98 00827 CRA 1701 W9DVM -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of dw Sent: Tuesday, July 14, 2009 12:26 PM To: Elecraft_List Subject: [Elecraft] The use of a doublet Great post Rick! Yes, the doublet has been over the years for me the easiest and best performing all band single antenna I've ever had. I feed mine with 450 also, but the top is only 135' long. I use the more robust SGC auto-tuner in external config. 40 feet of good quality coax and a high quality balun feed the tuner. With 20 watts applied, it finds best match in 3 seconds. It makes me feel like I'm cheating!! ;^D Duane N1BBR Hello Jim, I saw two of those tape measures once and they were actually part of a military dipole antenna system. The original antenna had 2 of them and you just pulled them ou to the coresponding frequency measurements on each side and you had a resonant dipole for that frequency. So if your friend used that to measue the wire with, then its most likely somewhere around 33 feet on each side. Being fed with 300 ohm balanced feedline makes your antenna a doublet - and a doublet is a very good all band antenna ! I use a doublet here that is 178 feet long - 89 feet per side and fed with 450 ohm feedline and it works 10 thru 160 meters via the tuner. 73 - Rick McKee, KC8AON Southern Ohio - EM88sn www.angelfire.com/electronic2/qrp With God all things are possible ~ ><(('> ~ -- [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 ______________________________________________________________ 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 |
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In reply to this post by dw-4
How do you establish that, "it really works"?
--- On Tue, 7/14/09, Phil LaMarche <[hidden email]> wrote: DX Engineering shared an antenna with me that I put up and it works wonderful on all bands with a tuner. 120 ft and fed with 90 ft of 300 ohm line into a 1:1 balun of theirs and into the tuner with RE 213. Tuner is a Palstar AT2K. The feed line length must be 90 feet. YES, it really works. Phil ______________________________________________________________ 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 |
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In reply to this post by Phil LaMarche-2
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The ladder line I purchased from DX Engineering is rated at full legal limit and 18 gage conductors with 19 strands of copper clad steel wire, resulting in a velocity factor of .88. Should it be larger? Phil Philip LaMarche LaMarche Enterprises, Inc. www.instantgourmetspices.com www.w9dvm.com 800-395-7795 pin 02 727-944-3226 FAX 727-937-8834 NASFT 30210 K3 #1605 CCA 98 00827 CRA 1701 W9DVM -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Ron D'Eau Claire Sent: Tuesday, July 14, 2009 1:16 PM To: 'Elecraft_List' Subject: Re: [Elecraft] The use of a doublet The beauty of a doublet is that the length of the radiator and the length of the feed line is completely unimportant if you have a wide-range tuner and the radiator is at least 1/2 wave end-to-end. With modern tuners -especially most "automatic" types - the feeder can present an impedance outside their matching range. That requires adjusting the feed line length to find something that will provide a match on all bands. Such an antenna should work as well or better than a dipole at equivalent height all frequencies at which it is at least 1/2 wavelength long. If good open wire line with a moderate impedance in the 450-600 ohm range is used, the line losses are very low thanks to the moderate SWR. Typically the SWR on any frequency will be less than 10:1, which won't result in significant losses if the conductors are of a decent size. Extremely high currents can flow at some points along the line, and large conductors help minimize the ohmic losses in the line. For that reason, 300 ohm "twinlead" or 450 ohm "ladder line" works, but has larger-than-necessary losses because of the small diameter conductors those lines use. Whenever possible, I use a #12 or larger wire for my open wire lines. At frequencies where the antenna is considerably longer than 1/2 wavelength, it shows some gain over a dipole with narrower but stronger lobes. It will work well down to where the antenna is only 1/4 wavelength end-to-end, showing only a small loss compared to a full size dipole. The problem there is that the SWR on the feeder jumps up as the impedance drops quickly at that size. Ron AC7AC -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Phil LaMarche Sent: Tuesday, July 14, 2009 9:32 AM To: 'dw'; 'Elecraft_List' Subject: Re: [Elecraft] The use of a doublet DX Engineering shared an antenna with me that I put up and it works wonderful on all bands with a tuner. 120 ft and fed with 90 ft of 300 ohm line into a 1:1 balun of theirs and into the tuner with RE 213. Tuner is a Palstar AT2K. The feed line length must be 90 feet. YES, it really works. Phil ______________________________________________________________ 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 ______________________________________________________________ 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 |
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In reply to this post by AC7AC
Ron D'Eau Claire wrote: Extremely high currents can > flow at some points along the line, and large conductors help minimize the > ohmic losses in the line. For that reason, 300 ohm "twinlead" or 450 ohm > "ladder line" works, but has larger-than-necessary losses because of the > small diameter conductors those lines use. Whenever possible, I use a #12 or > larger wire for my open wire lines. > It will work well down to where the antenna is only 1/4 wavelength > end-to-end, showing only a small loss compared to a full size dipole. The > problem there is that the SWR on the feeder jumps up as the impedance drops > quickly at that size. > I noticed an improvement with my DJ4VM quad, which is a balanced 2 el design for 20M, but works with gain on the other HF bands. No problem on 20 and above, but I found that feeding it with 450 ohm twin on 30M where the impedance is low was a problem. I got round it by putting a 9:1 balun between the element and the line. Now, having beefed up the guage of the element itself, it tunes 30m without the balun and I can get 599 reports from the East Coast USA on my 10 watt K3. Good f/b also. It would seem from what you say Ron, that increasing the feeder guage may be make it even better. Another not unexpected result was experienced when using a G4LNA quad loop, a vertical square about 25 feet each side for 160M http://www.qsl.net/g4lna/pages/myant.html This is fed with 50ohm coax to a step down transformer on a ferrite ring. The secondary goes to a series variable C then on to the loop. Mounted only anout 2 feet above group, this radiates a big signal on topband for its size and was only a couple of s points down on my half wave doublet. I thought I'd be clever and ditch the transformer and slap the 450 ohm line straight on to the loop and let the balanced tuner handle it. Guess what. The SWR was perfect - but everything was being lost in the line / and or the tuner. The G5RV is another story. Everyone misuses these antennas. They should be fed balanced all the way and they become - a doublet. As most folk use them, with a balnced transformer into, hopefully, a balun, then coax into a tuner. This is a definate no no. The transformer can only be right for a given frequency and that will change with height above ground, whether the elements are horizontal or inverted V etc. Nothing wrong with a 5RV if fed directly with balanced line - but you would be better cutting it as an extended double zepp for 20 and get 3DBd gain. 73 John Petters www.traditional-jazz.com Amateur Radio Station G3YPZ -- John Petters www.traditional-jazz.com Amateur Radio Station G3YPZ ______________________________________________________________ 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 |
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In reply to this post by Phil LaMarche-2
I've used the less expensive flat 300 ohm TV twinlead at the legal limit
(unknown velocity factor, unknown quality, etc) and it worked very well .... and never melted any of it! But .... if you're willing to pay for the "bigger & better" feedline, I am very sure that although it will work much the same, it will look incredibly better! And WorldRadio will publish the pictures to prove it. 73 Hank K8DD Phil LaMarche wrote: > The ladder line I purchased from DX Engineering is rated at full legal limit > and 18 gage conductors with 19 strands of copper clad steel wire, resulting > in a velocity factor of .88. Should it be larger? > > Phil > > > Philip LaMarche > LaMarche Enterprises, Inc. > www.instantgourmetspices.com > > www.w9dvm.com > 800-395-7795 pin 02 > 727-944-3226 > FAX 727-937-8834 > NASFT 30210 > > K3 #1605 > > CCA 98 00827 > CRA 1701 > > W9DVM > 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 |
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I thought the wire gauge was of little importance with parallel feeder,
since the energy flow is between the wires not in them. The insulation is of more importance. You might want something stronger for mechanical reasons. I used that pink tv twin many years ago and learnt that the terminations need to be well sealed to prevent water ingress. It is lightweight and thus adds little to drag the feedpoint down (catenary), however, I had to take a lot of care at the joints to relieve wind stress which otherwise causes breakages. David G3UNA Subject: Re: [Elecraft] The use of a doublet > I've used the less expensive flat 300 ohm TV twinlead at the legal limit > (unknown velocity factor, unknown quality, etc) and it worked very well > .... and never melted any of it! > But .... if you're willing to pay for the "bigger & better" feedline, I > am very sure that although it will work much the same, it will look > incredibly better! And WorldRadio will publish the pictures to prove it. > > 73 Hank K8DD > > > > Phil LaMarche wrote: >> The ladder line I purchased from DX Engineering is rated at full legal >> limit >> and 18 gage conductors with 19 strands of copper clad steel wire, >> resulting >> in a velocity factor of .88. Should it be larger? >> >> Phil >> 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 |
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In reply to this post by dw-4
This is simply untrue on all counts. Is wire size unimportant in AC power circuits? Of course not. Larger wire simply has lower resistive loss. Ohm’s law is still in effect at radio frequency. And for a given size, as the frequency increases, the resistance increases due to skin effect. So wire size can be more important at h-f. Also, assuming that the dielectric is mostly air, polyethylene or something comparable, the loss due to the dielectric is immaterial for all practical purposes. --- On Tue, 7/14/09, David Cutter <[hidden email]> I thought the wire gauge was of little importance with parallel feeder, since the energy flow is between the wires not in them. The insulation is of more importance. You might want something stronger for mechanical reasons. ______________________________________________________________ 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 |
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In reply to this post by dw-4
Maybe notes 10 and 11 here:
http://k6mhe.com/n7ws/ will be helpful. --- On Tue, 7/14/09, Ron D'Eau Claire <[hidden email]> wrote: From: Ron D'Eau Claire <[hidden email]> Subject: Re: [Elecraft] The use of a doublet To: "'David Cutter'" <[hidden email]>, "'.hank.'" <[hidden email]>, "'Phil LaMarche'" <[hidden email]> Cc: "'Elecraft_List'" <[hidden email]> Date: Tuesday, July 14, 2009, 5:02 PM Quite true, David, but that energy flowing along the feed line induces currents in the feeder wires as the currents produce the field. Those currents can be considerable at the current loops, even at low RF power levels and, considering that the current is flowing along the surface of the wire, the resistance of the wire at RF is much greater than at dc. It's my understanding that it's that resistance that cause feeder losses you see on the loss vs. frequency "curves" as the SWR rises above 1:1. That's why the "curves" are straight lines. They represent simple resistance. Of course, what makes open wire feeders superior to coax is that the practical impedance of coax is limited to fairly low levels, meaning much higher SWRs when terminated at a voltage loop on the radiator. In practical antennas that voltage loop may show as much as 4,000 ohms, resulting in a very high SWR on a 50 or 75 ohm line but a rather modest SWR on 450 or 600 ohm line. Of course that holds down the current maxima. I have not done a numerical analysis of the loss of open wire line using small vs. large conductors. Obviously, large conductors offer lower resistive losses but I, too, have used small diameter feed line conductors for light weight when I had to let the antenna carry the weight of the feedline. I'd not panic over using 450 ohm or, in a pinch, even 300 ohm "twinlead" if that was what was fit the situation. But when I can, I use larger wire. Even so, in my overflowing notebook of "experiments I'd like to do" is to set up, say, 100 feet of open wire line and terminate it in an impedance that produces an SWR of, say 10:1, then measure the loss with different diameter conductors. Antennas are like any other part of our gear: if we stick with what the manufacturers offer us, it's pretty simple. But manufacturers are trying to address the biggest audience with the most fool-proof designs. They can be good performers too, but that's not their most important criteria. Us O.T.s learned that with the Gotham vertical decades ago and the newer Hams are seeing it in the absurd claims of gadgets like the "magic" antenna. In both cases "performance' is a distant concern to the manufacturer compared to a broad appeal based on the idea that they are very easy to set up and use. At the other extreme are a very few options requiring specific installations and environments for proper performance. If we have the room and money for a tower or some really high poles, we're in luck. If not, we're pretty much "on our own" designing the best antenna for our individual situations. I find that part of the fun -- and part of the frustration when I'm convinced I did it wrong, Hi! I generally install my doublets "inverted V" style if I have only one support and run the open wire feeder up the support. If it's metal I keep it several line spacings from the support, of course. That way the weight of the feeder is unimportant and it's easy to install it so it's stable and free from twisting. I can use rather large wire easily. 73, Ron AC7AC -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of David Cutter Sent: Tuesday, July 14, 2009 3:01 PM To: .hank.; Phil LaMarche Cc: 'Elecraft_List' Subject: Re: [Elecraft] The use of a doublet I thought the wire gauge was of little importance with parallel feeder, since the energy flow is between the wires not in them. The insulation is of more importance. You might want something stronger for mechanical reasons. I used that pink tv twin many years ago and learnt that the terminations need to be well sealed to prevent water ingress. It is lightweight and thus adds little to drag the feedpoint down (catenary), however, I had to take a lot of care at the joints to relieve wind stress which otherwise causes breakages. David G3UNA Subject: Re: [Elecraft] The use of a doublet ______________________________________________________________ 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 ______________________________________________________________ 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 |
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In reply to this post by AC7AC
Can anyone point to why the single coil Z match wasn't commercialised rather than the T match? (Perhaps it's a historical thing and manufacturers just copy each other, notwithstanding the Johnson Matchbox of course, which is no longer produced.)
I'm in process of building one to cover 160 to 10 from VK2BR (?). I'm hoping that the link coupling will help with "balanced" feeders and antennas, though one side is bound to have more capacitance to earth than the other, so "balanced" is fairly relative. David G3UNA ______________________________________________________________ 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 |
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That should be VK5BR Lloyd Butler
http://users.tpg.com.au/users/ldbutler/SingleCoilZMatch.htm David G3UNA ---- [hidden email] wrote: > Can anyone point to why the single coil Z match wasn't commercialised rather than the T match? (Perhaps it's a historical thing and manufacturers just copy each other, notwithstanding the Johnson Matchbox of course, which is no longer produced.) > > I'm in process of building one to cover 160 to 10 from VK2BR (?). I'm hoping that the link coupling will help with "balanced" feeders and antennas, though one side is bound to have more capacitance to earth than the other, so "balanced" is fairly relative. > > David > G3UNA > ______________________________________________________________ > 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 ______________________________________________________________ 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 |
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In reply to this post by David Cutter
For years I've used a a Z-match tuner I built using very husky
components - big transmitting variables, salvaged 3" diameter silver plated tank coil and a 9:1 gear reduction drive for the main tuning cap. It works very well tuning a doublet fed with 450 ohm window line -- but even with the 9:1 reduction tuning can be very sharp. It's also more sensitive to slight variations caused by antenna movement etc. since you're tuning for near resonance. Those may be reasons it wasn't commercialised (much). In comparison, the Palstar BT1500A balanced L tuner I acquired a while back is less "fussy" - tuning isn't nearly as fast or critical. It also has the virtue of highly repeatable settings - it's quicker and easier to hop from band to band. Bob NW8L On Wed, Jul 15, 2009 at 3:44 AM, <[hidden email]> wrote: > Can anyone point to why the single coil Z match wasn't commercialised rather than the T match? (Perhaps it's a historical thing and manufacturers just copy each other, notwithstanding the Johnson Matchbox of course, which is no longer produced.) > > I'm in process of building one to cover 160 to 10 from VK2BR (?). I'm hoping that the link coupling will help with "balanced" feeders and antennas, though one side is bound to have more capacitance to earth than the other, so "balanced" is fairly relative. > > David > G3UNA ______________________________________________________________ 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 |
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In reply to this post by David Cutter
Is there any reason why SCAN could not be made to operate on the
current paramters displayed in the VFOs? A lot of times I want to scan a range without storing it in a memory location. As it is now, in order to SCAN the current VFO settings you have to go through six steps: V>M dial in a memory location V>M M>V M>V SCAN Why not just SCAN alone? This would be a lot more agile. 73, Drew AF2Z ______________________________________________________________ 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 |
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Is there any way to reduce the LED brightness when "LCD Brt" is set to
"dAY"? It seems the LEDs default to an extremely bright state when the LCD backlight is turned off. 73, Drew AF2Z ______________________________________________________________ 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 |
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In reply to this post by David Cutter
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In reply to this post by drewko
It appears to me that the LCDs have only one brightness, none! Only the back light has brightness. When set to DAY the back light is off and the contrast is just from the reflection on the back plane versus opaque for the activated elements. I didn't know there was a Day setting until your post even after a few thousand contacts over the past year. Willis 'Cookie' Cooke K5EWJ --- On Wed, 7/15/09, drewko <[hidden email]> wrote: > From: drewko <[hidden email]> > Subject: [Elecraft] K3 LED/LCD brightness > To: [hidden email] > Date: Wednesday, July 15, 2009, 8:47 AM > Is there any way to reduce the LED > brightness when "LCD Brt" is set to > "dAY"? It seems the LEDs default to an extremely bright > state when the > LCD backlight is turned off. > > 73, > Drew > AF2Z > > ______________________________________________________________ > 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 > 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 |
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Cookie,
The LEDs are the ones on the Shift, Width, etc. knobs; they become extremely bright when "LCD Brt" (display backlight) is set to "dAY" (or off), and there is no way to adjust them because "LED Brt" is no longer functional (it just beeps when you spin the vfo). Only when "LCD Brt" is set at some value 1 to 8 can "LED Brt" be adjusted. I checked the above text about five times for proper use of LED vs LCD... it can get a little confusing, hahah Anyhow, I'd like to use the LCD "day" setting and also be able to adjust the LED brightness down. 73, Drew AF2Z On Wed, 15 Jul 2009 09:58:49 -0700 (PDT), you wrote: > >It appears to me that the LCDs have only one brightness, none! Only the back light has brightness. When set to DAY the back light is off and the contrast is just from the reflection on the back plane versus opaque for the activated elements. I didn't know there was a Day setting until your post even after a few thousand contacts over the past year. > >Willis 'Cookie' Cooke >K5EWJ > > ______________________________________________________________ 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 |
Re: K3 LED/LCD brightness
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In reply to this post by drewko
drewko wrote: > Is there any way to reduce the LED brightness when "LCD Brt" is set to > "dAY"? It seems the LEDs default to an extremely bright state when the > LCD backlight is turned off. Interesting. The "LED BRT" setting seems to be disabled when "LCD BRT" is set to "dAY". Perhaps that could be fixed (to allow a separate day-time "LED BRT" setting). Personally I find the LCD difficult to read in "dAY" mode anyway, but the glaring LEDs do make it even worse... ~Iain / N6ML ______________________________________________________________ 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 |
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