Re: [Elecraft] KPA500 Voltage?
PS: Only the mains line is aluminum and connections treated with antioxidant paste. All new wiring in the new hamshack is copper (12-2 for 120vac and 10-3 for 240vac). The 3000w Meanwell 50v PS is served with a short 10-3 line to a 30A twist-lock receptacle in a floor mounted utility box with three foot 8-3 jumper to the PS (All copper). Max load is 12.5A; fused at 15A. Meanwell has internal overload and overtemp auto shutdown. Main thermostat (3000w) is programmable, so heat load will only be highest when the area is occupied. The workshop has manual thermostat which can be turned off when shop not in use (dividing wall is insulated between hamshack and workshop). The building will have a monitored (24/7) security system with smoke monitors. Monitor service calls police/fire dept if no one answers the phone. Two FD stations within five miles. I guess I could add thermistors to the mains contacts to alert overtemp. I use such a system on my QRO amp heatsinks to protect the amps (auto-overtemp shutdown of B+). I will monitor initial application of 240vac power to look for problems. In my college years I was a Electrician assistant for one summer job and got a good practical education installing ckts (even 440 industrial). Thanks for all the comments! Ed - KL7UW __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 #8862 unwanted sidebands
Thanks, Wes! As a 99.9% CW operator, I never looked into the Tech Mode options for SSB testing in my K3. That's a really useful feature! It's good to be reminded of the built-in troubleshooting utilities in the K3. 73, Mike, K8CN __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 #8862 unwanted sidebands
The K3 has a built-in two-tone generator. I've done 100s of two-tone IMD tests on my K3 and K3S using them and an SDR-IQ as a spectrum analyzer. Wes N7WS. On 11/15/2022 11:37 AM, Michael Carter wrote: Hi Martin, Do you observe (or hear) sidebands outside the nominal transmitted bandwidth with CW transmissions or only SSB transmissions? Can you perform a 2-tone test with an audio source other than speech? The fact that the unwanted sidebands are not observed when the KPA3 100 watt amplifier is bypassed suggests a possible change in the bias point of the PA transistors. If you have the original BJT version of the KPA3, not the LDMOS version of the KPA3A, perhaps you can measure the base or collector bias current when the KPA3 is engaged (PWR control set at 12 watts or above) with no audio modulation applied. That may be difficult to do without temporarily lifting a component lead. Perhaps Keith, WE6R from Elecraft can suggest a way of confirming proper bias point setting for the KPA3 without too much intrusion? 73, Mike, K8CN __ 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 Message delivered to wes_n...@triconet.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 Message delivered to arch...@mail-archive.com
[Elecraft] New K4 beta software release (R32.B1)
K4 beta release R32.B1 is now available. This release corrects a problem with TX DVR message play, where interrupting playback could sometimes disable microphone audio. (Just in time for the next big SSB contest) I'd like to thank our intrepid Field Test group as well as our software team for finding and fixing this challenging bug. There are also a few other bug fixes, as well as some new or enhanced remote control/macro commands. Full release notes appear below. 73, Wayne N6KR = == R32.BETA1 = November 14, 2022 = BUG FIXES = - TERMINATION OF DVR MESSAGES no longer causes occasional loss of mic audio. - REPEATER OFFSETS are now correctly applied to VFO B when in SPLIT. - IMPROVED EEPROM DATA VERIFICATION. = FOR SOFTWARE DEVELOPERS & MACRO USERS = - DUPLICATE "TX;" COMMAND while in transmit mode no longer exits transmit. - ADDED "EE0;" command to reset all radio state and menu parameters to defaults, with the exception of factory calibration data. - ADDED "TQX" GET COMMAND (extension to "TQ" TX status query): If the GET query is "TQ;", then the K4 is considered to still be in transmit mode during the S-meter holdoff time (300 ms), even though receive audio can be heard. If the GET query is "TQX;", then the S-meter holdoff time is not considered to be part of the transmit state. This allows an application to find out more quickly when actual RF transmit has ended, which may result in a more responsive user interface (when playing DVR messages, for example). - ADDED "AG$+nnn" (AF gain increment/decrement). - ADDED "VC" command to properly handle configuration of per-mode coarse tuning steps. "VT" command also improved to correctly handle A/B VFO swaps, etc. - IMPROVED "#HWFC" command to allow modification of waterfall color mode for both panadapters on the external monitor. __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 #8862 unwanted sidebands
Hi Martin, Do you observe (or hear) sidebands outside the nominal transmitted bandwidth with CW transmissions or only SSB transmissions? Can you perform a 2-tone test with an audio source other than speech? The fact that the unwanted sidebands are not observed when the KPA3 100 watt amplifier is bypassed suggests a possible change in the bias point of the PA transistors. If you have the original BJT version of the KPA3, not the LDMOS version of the KPA3A, perhaps you can measure the base or collector bias current when the KPA3 is engaged (PWR control set at 12 watts or above) with no audio modulation applied. That may be difficult to do without temporarily lifting a component lead. Perhaps Keith, WE6R from Elecraft can suggest a way of confirming proper bias point setting for the KPA3 without too much intrusion? 73, Mike, K8CN __ 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 Message delivered to arch...@mail-archive.com
[Elecraft] KPA500 Shifting Bands without any change in K3 Frequency
"It can't be solved. The SSB and/or Data at that AF MARS frequency is just slightly below the band pass filter change over to the 5.3 bandpass filter on the KPA500. That means that when you are on SSB, part of your rf envelope crosses over to the 5.3 band filter which causes the amp to switch to the higher bandpass (5.3) and when the rf at the frequency stops, the amp switches back to the 3.5 bandpass."" A similar problem was solved in the KAT500 by allowing the user to decide how much "importance" to assign the the RF detected frequency. This was a welcome change from the Elecraft philosophy that "RF knows best and will be obeyed". KPA500 doesn't have any published command that will prevent RF detected frequency from taking priority over a band or frequency command and it's not a problem when operating in the amateur bands the KPA500 was designed for. I see no reason the problem could not be solved for MARS users by a hardware mod that disables RF frequency detection. There is obviously some risk that the amplifier could be damaged if normal band switching fails and RF detection has been defeated. There are several undocumented KPA500 serial commands that I became aware of as I developed my station controller software. You could ask support if there is a command that allows the RF power required for band change to be user specified. 73, Andy, k3wyc __ 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 Message delivered to arch...@mail-archive.com
[Elecraft] KAT-500 tuner antenna switching
"And what I am finding is that the tuner switch can only identify the two and not the third one. Any recommendations on where I should begin to sort this out?" ANT availability for selection can be configured by band. Connect the KT500 utility and use it to set your antenna configuration preferences. An antenna port that is not enabled will not be selectable using the front panel ANT switch. Andy, k3wyc __ 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 Message delivered to arch...@mail-archive.com
[Elecraft] KAT-500 tuner antenna switching
For years, I had only two antennas to switch at the tuner, but I have now strung a third one. And what I am finding is that the tuner switch can only identify the two and not the third one. Any recommendations on where I should begin to sort this out? Thanks, gang! -- 73 de Ted Edwards, W3TB and GØPWW and thinking about operating CW: "Do today what others won't, so you can do tomorrow what others can't." __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 #8862 unwanted sidebands
I may have had the same issue as you. Elecraft instructed me to listen to my SSB signal via the monitor, start at 10watts and as you speak start increasing the power. When you reach 12-15 watts I bet you will hear your audio become distorted, sounds sort of like RF on your audio. If not then you have a different issue. You may want to try that test. For me it require a trip to the factory for repair. Rich On 11/15/2022 8:27 AM, Martin Schmiedel wrote: Elecrafters, i have 2 K3's, #8862 and #2878. Listeners using Panorama adapter gear like P3 or sdr radios report unwanted strong sidebands when #8862 i bought from a friend is in use. All is fine when #2878 is in use with same settings, power, external amp, antenna and same mic. The signal itself inside the ~3khz passband is fine, both K3's sound about the same , all ok. One listener said, the problem vanishes, when power is below 12W (only low power stage in use). I build a K2 (#2706) and the K3 #2878 myself, so i'm not scared to take #8862 apart to find the cause. Where to begin? TNX. -- 73, Martin __ 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 Message delivered to rwnewbo...@comcast.net __ 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 Message delivered to arch...@mail-archive.com
[Elecraft] K3 #8862 unwanted sidebands
Elecrafters, i have 2 K3's, #8862 and #2878. Listeners using Panorama adapter gear like P3 or sdr radios report unwanted strong sidebands when #8862 i bought from a friend is in use. All is fine when #2878 is in use with same settings, power, external amp, antenna and same mic. The signal itself inside the ~3khz passband is fine, both K3's sound about the same , all ok. One listener said, the problem vanishes, when power is below 12W (only low power stage in use). I build a K2 (#2706) and the K3 #2878 myself, so i'm not scared to take #8862 apart to find the cause. Where to begin? TNX. -- 73, Martin __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA500 Shifting Bands without any change in K3 Frequency
GM Joe, It can't be solved. The SSB and/or Data at that AF MARS frequency is just slightly below the band pass filter change over to the 5.3 bandpass filter on the KPA500. That means that when you are on SSB, part of your rf envelope crosses over to the 5.3 band filter which causes the amp to switch to the higher bandpass (5.3) and when the rf at the frequency stops, the amp switches back to the 3.5 bandpass. It is not that noticeable at SSB operations because most men's vocal range does not stay or reach up high enough to trigger the switch. On data, however it's a different story. Since the M101 waveform has a bandwidth of 2.8 KHz, your signal is almost always going to cross over that "flash point" causing the amp to go from OPER to STBY and vice-a-versa. There is a slight delay in the switching because of what I believe, are the high and low thresh holds of the filter frequency change point. There is also some delay in the changeover since again, what I believe is a hardware/software operation which says "I know you have change to a higher/or lower frequency, but I am not going to change to the correct band pass filter until - say 100 milliseconds later, because you might not have meant to do this". That's just a rhetorical guess on my part. I brought this problem up with Elecraft some time ago so they know about the MARS Radio. Elecraft said there could be a software solution to move the trip points up a little bit. There were not, however, going to do it because the demand for the change is too low, there would be a lot of effort to test the modification and finally, it would be a another parallel version of the product to maintain. Hope this helps With best regards, Jerry, W1IE, AFA3GK -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Joe Rogers Sent: Monday, November 14, 2022 21:00 PM To: elecraft@mailman.qth.net Subject: [Elecraft] KPA500 Shifting Bands without any change in K3 Frequency I am operating the KPA500 KAT500 power combo with the K3. The combination works great and normally makes frequency and antenna changes really simple. I operate on MARS frequencies and normally all works just fine outside of all the amateur bands with the KPA500/KAT500/K3 there is, however, one frequency where there is an issue. When transmitting at about 4.5 MHz using SSB or digital modes, using the KPA500/KAT500/K3 combination, the band indication shoes the KPA500 spuriously shifting back and forth between 3.5 and 5.3 MHz bands. This also affects the amplifier output power. I can also hear what sounds like contact/relay cycling. This makes the combo unusable on this frequency. How can I resolve this problem so that the KPA500 is usable on this frequency? 73 Joe AJ1Y __ 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 Message delivered to w...@jetbroadband.com -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Joe Rogers Sent: Monday, November 14, 2022 21:00 PM To: elecraft@mailman.qth.net Subject: [Elecraft] KPA500 Shifting Bands without any change in K3 Frequency I am operating the KPA500 KAT500 power combo with the K3. The combination works great and normally makes frequency and antenna changes really simple. I operate on MARS frequencies and normally all works just fine outside of all the amateur bands with the KPA500/KAT500/K3 there is, however, one frequency where there is an issue. When transmitting at about 4.5 MHz using SSB or digital modes, using the KPA500/KAT500/K3 combination, the band indication shoes the KPA500 spuriously shifting back and forth between 3.5 and 5.3 MHz bands. This also affects the amplifier output power. I can also hear what sounds like contact/relay cycling. This makes the combo unusable on this frequency. How can I resolve this problem so that the KPA500 is usable on this frequency? 73 Joe AJ1Y __ 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 Message delivered to w...@jetbroadband.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 Message delivered to arch...@mail-archive.com
