[Elecraft] RE: K2 #4039 - Distorted transmit audio
Hi, The distorted audio moves with the Control board, so either K2 can enjoy distorted transmit audio, if it has the faulty board fitted! Just to clarify point 3. The 12v rail seemed to modulate on both K2's when using either the faulty ** OR ** the working Control board! As this effect is the same for both K2's with either Control board. This would seem to indicate it is some other measurement (etc) effect, that we are seeing? Thanks again!!! Regards Nicolas Original posting. Hi, Following reports of poor transmitted audio, and aided by a fellow K2 owner we set about a little investigation. What happens.. Raspy, clipping?, (distorted by RF?), almost Dalek (For UK readers!!), sounding transmit audio. We checked the various board, joints etc, swapped things with the known working K2 and established.. 1. The issue is with the control board, when swapped, it gives the same fault in either K2. 2. No obvious component problems. 3. Another interesting observation on both K2's, was how the 12v rail modulates when you transmit? Any suggestions, where / what to look for on the control board, or other ideas? Thanks!!! Regards Nicolas www.m1hog.com --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.808 / Virus Database: 550 - Release Date: 08/12/2004 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] Re: K2 Muting
Hi Bob, Do you want to do SO2R with the 2nd K2? I have been running two K2s, SO2R using either TRLog or CT with an old laptop and a W4AN type homebrew switchbox. The laptop has only one serial port, so I switch the KIO2 lines with a multi-pole relay - not elegant, but it works. If that's what you're looking for, I'll send details. 73, Ken ZL1AIH ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] Re: Elecraft Digest, Vol 8, Issue 10
--- John W2XS wrote: The 42-foot wire received slightly lower signal reports than the inverted V, but most people said that they could still hear me fine on the wire. To my surprise, though, most people reported no real difference with and without the counterpoise. I don't know if this was a circumstance of my particular installation, but I would have thought that the counterpoise would make more difference. --- end of quote --- John, I've read in a number of places that the counterpoise should ideally be slightly longer than the antenna wire. Perhaps that is why little difference was noted. 73, Charlie N1AOK ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] FS Ten Tec Delta 580 FS
Hi Folks,I have a TT 580 Delta with CW filter excess to my needs,I am offering it for 325 shipped,USA. it is in good working and in good shape cosmetically. It has WARC bands also,as always, the price is negotiable. Thanks and Feliz Navidad! John KF7OM 72' Fallon, Nv. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Re: Elecraft Digest, Vol 8, Issue 10
Mychael Morohovich wrote: Instead of a 1/4 wl wire, I use an MFJ Artificial Ground to tune a wire for maximum current per given band. While measuring, one thing that surprised me was to discover that with my 86' EFW, the use of a properly tuned counterpoise didn't always increase the current to the radiator. For example, on 40 meters the use of a counterpoise helped to realize a substantial increase of current into the radiator, while on 80 meters I actually saw more current into the radiator with the counterpoise unhooked on that band. The effects on 30-10 were really fairly minimal or neutral in this regard. Keep in mind that you are measuring the current in the radiator AT A PARTICULAR POINT. Due to the standing waves on the radiator, that current varies depending on where you measure it. Now, since the 'antenna' you are feeding consists of the counterpoise PLUS the radiator, tuning the counterpoise will change the current distribution on the whole system. So measuring the current at the original point on the radiator does not tell the whole story. Perhaps adding the counterpoise has moved the maximum current point away from the feedpoint (a desirable situation)? What you can do is listen to distant stations while connecting and disconnecting the counterpoise. That will test the overall effectiveness of the antenna. Of course, the counterpoise will also change the horizontal and vertical pattern of the antenna, so you will need to listen to a large number of distant stations to control for this effect! -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Re: Elecraft Digest, Vol 8, Issue 10
Vic, K2VCO, wrote: Keep in mind that you are measuring the current in the radiator AT A PARTICULAR POINT. - The counterpoise is tuned for maximum current at the *rig*! The idea is that the more current flowing into the counterpoise for a given power output the lower the RF voltage at the rig. The objective is to provide the lowest impedance RF Ground at the rig. A well-tuned 1/4 wave wire does a very good job, of course. A 1/4 wave wire shows an impedance of about 35 ohms. Parallel several and you can reduce that proportionately. The problem is that in many situations it's not possible to carefully arrange even one resonant 1/4 wave wire, much less several. Many so-called grounds consisting of a random length wire thrown on the floor or a wire running several feet to a ground rod show an impedance at the rig in the hundreds of ohms, making the rig hot with RF. In that case a 35 ohm ground provided by a single tuned counterpoise is vastly superior for grounding the rig. Will it change the efficiency of the antenna? Perhaps. If the antenna is an end-fed 1/2 wave wire presenting an impedance of perhaps 2000 ohms to the rig, the difference in radiation efficiency will be negligible. One can consider the two resistances in series: the ground resistance, 35 ohms in this example, and the radiation resistance of the antenna, 2000 ohms in this example. If .1 amps is flowing inn that circuit, the rig is putting out 20.35. Of that 20 watts, 0.35 watts is dissipated in the counterpoise and 20 is radiated. The advantage of the counterpoise in this case is to keep the RF voltage at the rig down. It will tend to float to a high RF potential if there's no ground and cause all sorts of problems. If the antenna is shortened to 1/4 wavelength, then the efficiency drops to 50% with equal current and power in the counterpoise and antenna. That sounds awful but that is, in reality a very respectable figure for such an antenna. Many short vertical antennas have efficiencies of much less than 50%. As the antenna is made shorter than 1/4 wave long (that's overall physical length, adding a loading coil doesn't help the efficiency - it only helps match impedances) the radiation resistance plummets, and with it the efficiency unless a really, really good ground system is used. That's the ultimate challenge with anyone using a loaded monopole of any sort. There simply is no magic answer to efficiency for physically small antennas - until we get some really cheap, really good room-temperature superconductors to make them from... Ron AC7AC ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] MFJ 4103
Hi Elecrafters, Does any one have any info on the MFJ miniature psu type 4103? Although it is a sealed unit I wish to adjust the output to keep my internal battery charged. The nominal output voltage is 13.8 and I wish to adjust to give 14.2 as measured by the K2. I think the unit could be carefully cut open and after adjustment sealed up again. Before starting on this exercise I thought I would check with your collective wisdom. 73 Max/ZL4vv ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Antennas and counterpoise was Re: Elecraft Digest, Vol 8, Issue 10
Thanks for the good infoI am slowly learning. 73, Jim, AL7FS Ron D'Eau Claire wrote: -- Jim Larsen http://www.CSTAlaska.com/ http://www.AL7FS.us/ Anchorage, Alaska ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] Building Help in Florida
I have had a request from a new customer who would like to talk with an Elecraft customer and possibly get some help as he builds his K2/100. He is in the Boca Raton area and would like to talk with someone local. He may even need a little face-to-face help along the way. If you are interested please email me directly first, [EMAIL PROTECTED] Thank you and have a great weekend! Lisa ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Re: Elecraft Digest, Vol 8, Issue 10
Vic wrote: I was making the point that his experiment of unhooking the counterpoise and measuring the current into the radiator did not indicate that the counterpoise was or was not improving antenna performance. - The method I used was to first tune the antenna with my KAT100 for a flat SWR, tune the counterpoise for max current at the rig, then tweak both until the KAT100 reported a flat SWR for the antenna while the Artificial Ground reported maximum current into the counterpoise. Using the rf sensor, I measured the current of the antenna [and counterpoise because I was curious] at a spot close to the back of the rig. I then removed the counterpoise, retuned the antenna for a flat SWR, and measured the current again for reasons of comparison. This showed me the amount of current that was going into a properly tuned antenna both with and without a tuned counterpoise in place. Mychael ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] A big thankyou
Hi all, I would just like to take the time for a moment and thank Ron, AC7AC for his support and assistance in helping me get my XV144 working recently. As usual, I went about things the hard way and decided to run the transverter at low level from the KX60V. As it happened, the documentation had not yet caught up with the process and I got in a muddle. Ron was there immediately and his help was invaluable to me in getting the whole thing working. It is now working like a dream in exactly the way I wanted. Many thanks Ron! Ian -- Ian Maude G0VGS Morecambe Lancs UK | [EMAIL PROTECTED] Sysop of GB7MBC, the Morecambe Bay Cluster Running Linux and DXSpider | K2 #4044 Find out about Summits on the Air! Visit the SOTA web site at http://www.sota.org.uk ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] OT-Preserving CW memories
From time to time I make a post reminding folks that there's a web site where the content comes from a submarine radio operator (www.zerobeat.net/submarine) . I'd love to do a similar site with the memories and stories of folks who made their living pounding brass, whether aboard ship, at a Coast Station, Police Communications, Railroard or other venues. Yep...it appears that hardly anyone does any of the above now, and I'd like to preserve your memories on the web so that those of use that use and enjoy cw have a frame of reference other than amateur radiowhen you're not around, you'll take those memories with you. If ya have a mind to, drop me an emailI'll be happy to turn it into HTML and devote as much space on the server as it takes to tell the story of the magical music. 73,Thom-k3hrn www.zerobeat.net Home of QRP Web Ring, Drakelist home page, Free Classified Ads for amateur radio, QRP IRC channel Elecraft Owners Database www.tlchost.net/ Web Hosting as low as 3.49/month ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] Re: #4472 made my first Rtty contact with my K2
Finally got the K2 SSB kit to work and my first contact was with ZS6PVT, South Africa, on rtty at 5 watts. He had a hard time hearing me, but we exchanged reports fb. What a radio, thanks to all. Jerry, N2UZ ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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
