Re: [Elecraft] K3: Very distorted audio on transmit but only on 20m and only with the KPA500 on
Almost certainly RF getting into the mic circuit. Try a different mic .. or use the rear panel mic connector as a check. You probably have high SWR into the antenna feedline (or coax) after the tuner on 20 meters and that is why you only see problem on 20M. High SWR on the feedline (Note: your rig can be seeing low swr .. it is AFTER the tuner where you have high SWR) results in high current or high voltage that then couples into other shack wiring. Of course, the higher power from the KPA500 pushes those voltages/currents to levels that are more likely to cause problems. Been there, done that .. many times. Don K7FJ Ok, So my audio is quite distorted as I can hear in my headphones with the monitor. But this only happens on 20m and only with the KPA500 in operate. Sound like RF? or is something else going on? Thanks __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA500
Sounds about right to me. It varies a lot with the band in use .. mine runs hotter on higher frequency bands. I installed (reversible) modifications in my KPA500 to improve cooling just to keep the fan noise down. Don K7FJ On 6/23/2013 2:33 AM, Arie Kleingeld PA3A wrote: Hello, Just checking cooling performance my new KPA500. Running 330W output in RTTY, 50% duty cycle. SWR is OK: 1 : 1.1 or so. Ambiant temp = 25C Fan runs at speed 4, occasionally 5 PA TMP hovers between 65 and 70 C Is this normal? 73 Arie PA3A __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] annoying problem
If Jim's ideas don't work you could simply try another detector of a different brand. Susceptibility to RF varies in unpredictable ways and that is an easier solution than moving the detector (move it where? Would it actually help?). Another approach, if it is a 'wired-in' detector, is to replace it with a battery-only detector or, easier yet, just unplug the AC wiring connector and let it run on battery only as a test to see if that cures the susceptibility problem. If it does cure the problem you would probably need to replace the detector with a battery-only model which would probably run for a lot longer between battery changes because the wired-in type, when operating on battery only, can use up the battery pretty fast. If your detector is interconnected with other detectors so that they all sound the alarm if any one of them senses smoke then going battery only will defeat that feature and only you can decide if that is a prudent thing to do and in accordance with codes ( In my house all of my detectors are easily heard from all rooms). Don K7FJ On 2/1/2013 9:40 AM, Jim Wiley wrote: If it is a wired-in smoke detector, try putting a .01 uFd 1400-volt AC rated cap directly across 120-volt AC power leads. If that isn't enough, then try a capacitor the between (across) the wire, if there is one, that connects it to the other detectors and the AC neutral lead. If the unit is battery powered, try a .01 uFd 600 V cap across the detection chamber. That may work, but if not, get used to the idea of having to move it. Always test and verify proper operation of the unit by blowing actual smoke from burning wood matches into the unit after making any modifications of this nature. Pressing the test button is not enough - use actual smoke. - Jim, KL7CC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] KPA 500 Fan Noise
Toby, I am far more sensitive to fan noise than most folks and have spent a lot of time making my KPA500 much quieter by modifying it and by other means. This topic is probably not of interest to most on this list because, compared to most amps, the KPA500 is NOT loud (and many have said it is much quieter). Contact me off list and I will be happy to share my experience with you. Don K7FJ I have had the amp now about a year. The cooling fan is just fine when using SSB, but when on cw and running a while at full output, the fan comes on and sounds like it is going to take off from the table. It is really loud I have the fan speed set to 1, but wonder what others are doing to quieten the fan a little bit, or what fan speed you have the amp set to. OR WHATEVER Toby W4CAK __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] KPA 500 Fan Noise and cooling performance
On 6/18/2012 4:42 AM, David Robertson wrote: ( ... a long message I won't include here where he improved amplifier cooling by tightening heatsink/right panel screws and used heatsink compound.) I operate my KPA500 with the fan speed set to #1 continuously which delays the increase in the increase in fan speed once the amplifier starts putting out power. My amplifier did not exceed 58 deg C after 10 minutes at 500 watts carrier output into a dummy load and it stabilized at about 60 degrees in a 25 degree C room. My right panel to heatsink screws (the ones under the handle) were all tight and that explains why my experience was better than was Dave's originally before he tightened his heatsink screws and added heatsink compound. I then added heatsink compound to the mating surface between my heatsink and the right side panel. There was no difference in cooling performance at all. I just wanted to know .. and now I do .. and so do you. The KPA500 fan is as quiet as any muffin fan ought to be but it was still annoying to me. That is not an amplifier fault .. it is just that I have good hearing and I prefer a *very quiet shack. For those who may be like me in that regard here is how I reduced the normal fan noise of my amplifier. In my amplifier much of the fan noise was actually coming from the sheet metal of the amplifier structure which was being excited by the vibration of the fan which is rigidly attached to the amplifier structure so that fan vibration was communicated to the structure which then resonated and amplified the fan noise. When I removed the fan and held it loosely in my hand while it was running I could feel the light high frequency 'buzz' produced by the rotating magnetic field of the fan and also, crucially, the lower frequency throb caused by a slight weight imbalance in the rotor. I used a small piece of sticky pad (normally used to mount components to a chassis, etc) and placed this very small weight at various points on the rotor blades until, by trial and error, found the 'sweet' spot which resulted in greatly reduced throb. That reduced fan noise considerably. Then, to reduce transmission of fan vibration to the amplifier structure even further, I mounted the fan loosely to the back of the amplifier using soft quarter-inch cushions between the fan and the amplifier. I used light wire to do the actual attachment instead of the long screws that are standard. The overall effect is considerably less fan noise and I am very happy about that. The fan mounting is fragile and not to be recommended if the amplifier is to be moved very much but in my installation it is just fine. By the way, I carefully compared cooling performance before and after the fan mounting modification and found no difference at all. I also noticed during my testing that the direction of airflow makes no difference. Don K7FJ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] K3 KPA500 Oper/Stby Alert
I really like that idea. I never quite trust the lower power setting of the K3 when the amplifier is put on-line and always manually check it to be sure it is where I hope it is. It would be *much* better for the K3 to display the new power setting instead of those unnecessary 'KPA ... ' messages just as Fred suggested. Don K7FJ snip CHANGE: Replace both messages with one that tells me what the K3 power will be when I next tap the paddle [or talk]. I've got the two power levels for each band set, and most of the time it works. Occasionally, after adjusting the high power antenna tuner with just the K3 in TUNE [5W], going to OPER leaves the power at 5W. Once, it went to 100W which faults off the KPA500 instantly, of course. Occasionally, the K3 stays at low power when I go to STBY. 73, Fred K6DGW - Northern California Contest Club - CU in the 2012 Cal QSO Party 6-7 Oct 2012 - www.cqp.org __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] question for psk31 users
Sidebars are a visual indication of signal distortion .. not the power level being transmitted. You have a signal *quality* issue which is most often caused by overdriving . Don K7FJ On 4/30/2012 11:06 AM, KC6CNN wrote: I am now up and running on psk31. I had my power set to 25watts and all is well. If I try to increase it to 30 watts, people say I have side bars. OK not sure what that is, but running 25 watts. I see stations that say they are running 50 and even a 100 watts. How are they able to run so much power and I get the side bar things at 30 watts. Guess I should ask also what are sidebars. lol Thanks Gerald - KC6CNN -- View this message in context: http://elecraft.365791.n2.nabble.com/question-for-psk31-users-tp7514424.html Sent from the Elecraft mailing list archive at Nabble.com. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] New App __ spoof?
This is surely an April Fools spoof On 4/1/2012 11:19 AM, Tony Morgan wrote: Hey guys, Check this out, I downloaded it to my iPhone! https://mail.google.com/mail/help/promos/tap/index.html 73, Tony W7GO __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] OT-old vs. new 6L6 to K3
This is one oldtimer who actually used such a design. After more than 58 years I finally understand how it worked .. actually, not very well for me. Chirps and whoops were very common in those days and I can say with confidence that they were definitely acceptable and, in fact, were a characteristic of stations such as mine without the operator even knowing about the whoop. Remember, like many other novices I was using a simple regenerative receiver that could not be used for a monitor and never knew how my signal actually sounded in the other guys receiver. Even the more sophisticated superhets overloaded so easily that they did not provide a faithful reproduction of the outgoing rf. Don K7FJ The 6L6 keyed oscillator shown in the Flickr page is certainly a lovingly-crafted piece of artwork, but I am a bit skeptical about the implication that a techno-adept ham of the late '30's would have been pleased by the chirp. After all, the 6L6 first appeared in 1936, and by then the 'x' and 'c' of the RST/x/c reporting scheme was probably already in use. Keying an oscillator working directly into an antenna was understood to be a poor idea. The MOPA idea was around long before the 6L6. There is a QST article in 1934 illustrating the general idea of a 2-stage transmitter, and the idea was known long before that. John Ragle -- W1ZI __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] K3 Break in with an amp question
The powercube is definitely a ham amplifier. I know of at least one owner who is very happy with the one he has but, then, he only operates SSB. Most amps that use relay T/R switching (and that is *most* amps) do the clickety-clack thing. I know of failed relays that could not take the abuse. Your solution of using semi-breakin with an appropriate delay is the only way to avoid this problem. With my new KPA500 I no longer have that problem but, with my previous Tokyo HyPower amp, I used a homebrew PIN Diode switching system to do all of my T/R antenna switching with all solid state circuitry but that is not a trivial exercise. Don K7FJ On 3/17/2012 4:49 AM, gold...@charter.net wrote: I am attempting to slowly learn to work with CW but at first it is with a computer program but I am not sure if that is relevant. I understand the reason for break in as it allows for RX listening between your TX in case someone it trying to contact your. The issue is that when using VOX and with semi or full breakin when using my amp the relays in the amp are clicking and clacking like crazy which to me seems very abusive to the amp.My solution has been to go to semi break in and then set a long delay time so the amp and K3 stay keyed. The amp is an SGC powercube and I do have it wired to the K3 so it gets a PTT signal. Am I doing the right thing with the delay or are there other ways to stop the amp from going nuts or is this just the nature of the beast. ~73 Don KD8NNU __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] FW: K3: CW in SSB mode broken?
My K3 with Firmware 4.39 has the CW in SSB feature on all bands including 6 meters in VOX or non-VOX mode. I use it a lot and have never had a problem. Don K7FJ On 2/1/2012 1:48 PM, Joe Subich, W4TV wrote: On 2/1/2012 2:23 PM, W7GJ, Lance wrote: One thing that disappointed me is that this very useful cross-mode feature (at least on 6m, where I do most of my operating), is available only if you are running VOX mode. I am not sure why it has been excluded when you run with a footswitch or sequencer to trigger the PTT line. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] K3 has internal noise with high compression settings
Don, My first reaction is that compression of 35 is way too high. I never go over 15 or so because of all of the background noise in the shack that is picked up by the mic at high compression settings. Something of that sort is perhaps what you are hearing .. maybe a fan or other hum-like sound in the local environment. High compression makes the system super sensitive to low level sounds. Don K7FJ On 1/12/2012 9:58 AM, gold...@charter.net wrote: Gents, Last night I disconnected all the antennas and started to look at basics within the shack because of my antenna problem, I decided that I should check the basics with my dummy load and found an interesting thing happening inside my K3. What I found is that when directly connected to a dummy load and I run the k3 at full power 110 watts, as I dial up the compression above 35 on the settings , I hear a hum inside the K3 and it shows RF out power in SSB when I am not speaking into the microphone. Basically key up the mike in a quite environment in SSB mode and it goes into TX where there is output. I made a coax choke with snap on ferrites between the dummy load and the K3 to see if I could kill it but it made no difference. Also power settings below 110 did make some difference and mike gain had little to no effect. This happens on all frequencies, does not matter if on 160m or 10m. I then connected the amp between the K3 and dummy load and this noise starts at about a compression setting of 30 to 33. This is with a drive power of 40 watts into an SGC powercube, and when the humming started there was TX power on my meter. The internal noise sounds like a ferrite vibrating. Other items, power is supplied via 12v batteries using a floated battery charger, existing antennas were disconnected from the system. Is this something that others have seen or should I call Elecraft support. I am hoping I don't also have a K3 problem. Thanks Don ~73 Don KD8NNU __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
