Re: [Elecraft] KPA500 Failure
Dick, Here is a link to information on many Elecraft products. https://www.qsl.net/wb4kdi/Elecraft/index.html Scroll down and you will see the KPA500. You will see the schematic links. Select the Low Pass Filter. It is REV D2 dated 12/5/13. I believe that is the latest. The schematic I have is from 1/30/11. 73, Mark, WB9CIF -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Dick Bingham Sent: Thursday, May 2, 2024 02:16 To: elecraft@mailman.qth.net Subject: [Elecraft] KPA500 Failure -- An update on my KPA500 failure -- I extracted the amplifier/LPF assembly from the case and examined the two units: - Power FETs and all components *appear* to be OK - *LPF Module Rev D* bd appears to be what failed. The SM component positioned between C97, C110 and C111 *MAY* be C96 - hard to identify after cleaning the white vapor-deposited 'stuff' from the PCA using acetone solvent. There was what appeared to be a "tombstone-positioned" '*something*' sitting on a pad in the damaged area that I can not identify. I have not been able to locate a schematic or PCA picture for this LPF assembly to identify the missing component. If someone could provide a link to the Rev D LPF assy, I would appreciate it very much. 73 and TU to all who have, so-far, provided helpful suggestions. I am now waiting to hear what Elecraft's Service Department has to say about the failure info and picture I sent to them today. Dick/w7wkr __ 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 markmus...@outlook.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
[Elecraft] KPA500 Failure
-- An update on my KPA500 failure -- I extracted the amplifier/LPF assembly from the case and examined the two units: - Power FETs and all components *appear* to be OK - *LPF Module Rev D* bd appears to be what failed. The SM component positioned between C97, C110 and C111 *MAY* be C96 - hard to identify after cleaning the white vapor-deposited 'stuff' from the PCA using acetone solvent. There was what appeared to be a "tombstone-positioned" '*something*' sitting on a pad in the damaged area that I can not identify. I have not been able to locate a schematic or PCA picture for this LPF assembly to identify the missing component. If someone could provide a link to the Rev D LPF assy, I would appreciate it very much. 73 and TU to all who have, so-far, provided helpful suggestions. I am now waiting to hear what Elecraft's Service Department has to say about the failure info and picture I sent to them today. Dick/w7wkr __ 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 failure
Lyn Just a thought: the rig has a remote on/off facility and you may be getting extraneous signals into that port. I know nothing more, but it may give you a clue where to start looking. 73 David G3UNA -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Lyn Norstad Sent: 09 February 2023 15:57 To: Elecraft@mailman.qth.net Subject: Re: [Elecraft] KPA500 failure Here's another twist that makes me thing it could be a PS issue. Early this morning, I was hunting down 3Y0J on 10m FT8 (very strong signal here). WSJT-X was in F/H and S/P mode. I stepped out of the shack for a few minutes, and when I came back the KAP500 was powered ON, in Standby mode with the Fault LED lit up. It had been powered Off with the front panel switch since yesterday (the rear panel switch was ON as usual). How is that possible? Thx, Lyn -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Lyn Norstad Sent: Wednesday, February 08, 2023 4:00 PM To: Elecraft@mailman.qth.net Subject: [Elecraft] KPA500 failure A couple days ago, I stepped out of the shack for a few minutes and upon returning found the KPA500 had shut down. I didnt note any brief power outage, and Im quite sure it was ON when I stepped away. It has been a little quirky in keying since that time. Yesterday it gave off a funny smell and the Power and SWR LEDs were jumping up and down for no apparent reason. The display screen jumps to frequency readout when I key the exciter, no matter what it is set for. The KAT500 seems to be working normally with the amp either OFF or in Standby. I did a total power reset and reloaded the current firmware (v01.54), but no change. I have not pulled it apart yet, but I seem to remember these being the symptoms discussed some time ago that required an LPF rebuild. Somewhere along the line, Elecraft switched to a SM board and thats when the trouble started. So my question besides asking for general advice is if anyone knows the serial number when Elecraft made that change. My KPA500 is s/n 03835. Thanks! 73 Lyn, WØLEN __ 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 l...@lnainc.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 davidg3...@gmail.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
Re: [Elecraft] KPA500 failure
Here's another twist that makes me thing it could be a PS issue. Early this morning, I was hunting down 3Y0J on 10m FT8 (very strong signal here). WSJT-X was in F/H and S/P mode. I stepped out of the shack for a few minutes, and when I came back the KAP500 was powered ON, in Standby mode with the Fault LED lit up. It had been powered Off with the front panel switch since yesterday (the rear panel switch was ON as usual). How is that possible? Thx, Lyn -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Lyn Norstad Sent: Wednesday, February 08, 2023 4:00 PM To: Elecraft@mailman.qth.net Subject: [Elecraft] KPA500 failure A couple days ago, I stepped out of the shack for a few minutes and upon returning found the KPA500 had shut down. I didnt note any brief power outage, and Im quite sure it was ON when I stepped away. It has been a little quirky in keying since that time. Yesterday it gave off a funny smell and the Power and SWR LEDs were jumping up and down for no apparent reason. The display screen jumps to frequency readout when I key the exciter, no matter what it is set for. The KAT500 seems to be working normally with the amp either OFF or in Standby. I did a total power reset and reloaded the current firmware (v01.54), but no change. I have not pulled it apart yet, but I seem to remember these being the symptoms discussed some time ago that required an LPF rebuild. Somewhere along the line, Elecraft switched to a SM board and thats when the trouble started. So my question besides asking for general advice is if anyone knows the serial number when Elecraft made that change. My KPA500 is s/n 03835. Thanks! 73 Lyn, WØLEN __ 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 l...@lnainc.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
[Elecraft] KPA500 failure
A couple days ago, I stepped out of the shack for a few minutes and upon returning found the KPA500 had shut down. I didnt note any brief power outage, and Im quite sure it was ON when I stepped away. It has been a little quirky in keying since that time. Yesterday it gave off a funny smell and the Power and SWR LEDs were jumping up and down for no apparent reason. The display screen jumps to frequency readout when I key the exciter, no matter what it is set for. The KAT500 seems to be working normally with the amp either OFF or in Standby. I did a total power reset and reloaded the current firmware (v01.54), but no change. I have not pulled it apart yet, but I seem to remember these being the symptoms discussed some time ago that required an LPF rebuild. Somewhere along the line, Elecraft switched to a SM board and thats when the trouble started. So my question besides asking for general advice is if anyone knows the serial number when Elecraft made that change. My KPA500 is s/n 03835. Thanks! 73 Lyn, WØLEN __ 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 failure
Never mind, I solved my own cockpit problem. The transceiver has a different setting for 50 MHZ. All is good. On 11/26/2020 7:23 AM, Wes wrote: I've been incorporating a new transceiver into my station and was going through setting the per band power limits for driving my KPA500. When I got to 50 MHz, a band I seldom use, I was dismayed to note that there is no amplification, it operates as if in Standby. The RF frequency sensing fails to switch bands and even manually switching to 50 MHz makes no difference. I have the schematics, but it's unclear to me where to start. Any ideas welcome. Wes N7WS __ 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 failure
I've been incorporating a new transceiver into my station and was going through setting the per band power limits for driving my KPA500. When I got to 50 MHz, a band I seldom use, I was dismayed to note that there is no amplification, it operates as if in Standby. The RF frequency sensing fails to switch bands and even manually switching to 50 MHz makes no difference. I have the schematics, but it's unclear to me where to start. Any ideas welcome. Wes N7WS __ 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 failure
Don; Does the High Voltage look about right on the display? Do you still get the asterisk on the display when you key down? Give tech support a call in the morning. They will be best equipped to help you at this point. 73, Jack, W6FB > On May 12, 2019, at 6:54 PM, Don Roberts via Elecraft > wrote: > > While getting ready for the Elecraft net today my KPA500 would not transmit. > In bypass mode swr is 1:1. When placing in operate mode I get no output with > my K3 showing high swr. Tried my loop, vertical, and Hex beam. All show low > swr on the K3, KAT500 and the KPA500 in bypass. > I took the KAT out of circuit and no change. Unhooked all antennas and then > reattached one at a time, no joy. Ran a new coax between K3, KPA500, and then > just between the K3 and KPA500 and got the same thing. > Can run 100 watts out with K3 with low swr on all my hf antennas as long as > KPA500 is bypassed. When I put it in operate I get no output and K3 shows > high swr. It has been working flawless on all bands and modes. Usually run 28 > to 32 watts input for around 500 out. > Anyone have any ideas on what might have happened. Thanks for any thoughts.. > 73, > Don, W4CBS > Sent from Yahoo Mail on Android > __ > 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] KPA500 failure
While getting ready for the Elecraft net today my KPA500 would not transmit. In bypass mode swr is 1:1. When placing in operate mode I get no output with my K3 showing high swr. Tried my loop, vertical, and Hex beam. All show low swr on the K3, KAT500 and the KPA500 in bypass. I took the KAT out of circuit and no change. Unhooked all antennas and then reattached one at a time, no joy. Ran a new coax between K3, KPA500, and then just between the K3 and KPA500 and got the same thing. Can run 100 watts out with K3 with low swr on all my hf antennas as long as KPA500 is bypassed. When I put it in operate I get no output and K3 shows high swr. It has been working flawless on all bands and modes. Usually run 28 to 32 watts input for around 500 out. Anyone have any ideas on what might have happened. Thanks for any thoughts.. 73, Don, W4CBS Sent from Yahoo Mail on Android __ 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 Failure to turn ON
On Sun, Feb 24, 2013 at 11:17 AM, wrote: > After several attempts, my otherwise problem free KPA500 refused to turn on > using the front panel ON button. I cycled the rear panel master power switch > once. The front panel ON switch works again. > > Connectors, relays, switches, fuses - always the things to check first. This happens to mine once in a while... it seems to be a firmware hang, but I haven't found a way to reproduce it. It has led to unplanned hilltop remote site visits on a couple of occasions, and subsequent installation of network power switches ;) 73, ~iain / N6ML __ 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] KPA500 Failure to turn ON
After several attempts, my otherwise problem free KPA500 refused to turn on using the front panel ON button. I cycled the rear panel master power switch once. The front panel ON switch works again. Connectors, relays, switches, fuses - always the things to check first. 73 - Steve WB6RSE __ 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
