[Elecraft] Elecraft CW Net Report
Good Evening, Both bands were weak and unproductive. QSB was deeper on 20 than on 40 meters. Noise was higher this week. The web cams at the Geldingadalir volcano now have increased resolution and the sound is working. The sub-woofers are moving the house as the lava flies. I hope they are making a time lapse movie from this live feed. On 14050.5 kHz at 2200z: NO8V - John - MI K4JPN - Steve - Ga On 7047.5 kHz at z: W0CZ - Ken - ND K0DTJ - Brian - CA K6PJV - Dale - CA Until next week stay well. 73, Kevin. KD5ONS - The supreme accomplishment is to blur the line between work and play. - Arnold J. Toynbee __ 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 Question
On Sun, Apr 18, 2021 at 5:02 PM wrote: > > "When I engage OPER the input signal is attenuated by ~20 dB." > > Thanks to all for the prompt and informative replies. Apparently the culprit > has been found. Several reported the exact same issue, one as recently as > one week ago. According to one reply, an Elecraft Tech told him, "This is a > known failure mode." (Not very encouraging!) > Here is a copy of an Elecraft repair report: > > Reported problem(s): > Receive signal is attenuated when in operate. Receive signal is normal when > in standby. > > Problem(s) found: > Confirmed problem. Found that D8, D9 and R7 in the T/R circuit had failed. > > Repair(s) performed: > Replaced D8, D9, and R7 on the LPF board. > > Looks like my KPA500 is in for some "belly up" treatment! > One thing has me a bit puzzled though. If this is a known weakness, why > hasn't Elecraft designed a "beefed up" mod? My amp had 5 updates / mods done > while it was at the factory. This "known failure" was not one of them. There definitely has been "beefing up" of the T/R circuit over the years. I don't know about dates. You might find this interesting (although I think your failure is different - I've been "lucky" enough to experience both, and more): http://ok1rp.blogspot.com/2017/02/elecraft-kpa500-lpf-tr-switch-rework.html Mine when back in late 2019, and had the following performed (amongst other fixes and updates): "Replaced Q5, D7, R3, R9 and R24 for Transmit/Receive MOD (Improves robustness in Transmit/Receive circuitry)." Good luck getting a response from Elecraft support now. Apparently they don't respond to email any more (mine from April 5th has been ignored so-far, and I've seen similar reports from others here). 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] KPA500 Question
Point taken. FWIW: This "known failure" tech comment was in 2018. Jim - WS6X On Sun, Apr 18, 2021, 8:33 PM KENT TRIMBLE wrote: > Just because a tech says it's a known failure today doesn't mean it's > been a known failure throughout its production run. __ 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 Question
Just because a tech says it's a known failure today doesn't mean it's been a known failure throughout its production run. Component availability and sourcing necessarily change over the years. A robust component from a former supplier ten years ago may not be as robust from a different supplier today. There is no way of knowing which components exhibit early failures until they fail early. Consider yourself now an experienced beta-tester! 73, Kent K9ZTV On 4/18/2021 6:59 PM, someone wrote: According to one reply, an Elecraft Tech told him, "This is a known failure mode." ... If this is a known weakness, why hasn't Elecraft designed a "beefed up" mod? __ 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 Question
"When I engage OPER the input signal is attenuated by ~20 dB." Thanks to all for the prompt and informative replies. Apparently the culprit has been found. Several reported the exact same issue, one as recently as one week ago. According to one reply, an Elecraft Tech told him, "This is a known failure mode." (Not very encouraging!) Here is a copy of an Elecraft repair report: Reported problem(s): Receive signal is attenuated when in operate. Receive signal is normal when in standby. Problem(s) found: Confirmed problem. Found that D8, D9 and R7 in the T/R circuit had failed. Repair(s) performed: Replaced D8, D9, and R7 on the LPF board. Looks like my KPA500 is in for some "belly up" treatment! One thing has me a bit puzzled though. If this is a known weakness, why hasn't Elecraft designed a "beefed up" mod? My amp had 5 updates / mods done while it was at the factory. This "known failure" was not one of them. Thanks again, for all the help! Jim - WS6X __ 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 Question
What happens if you reduce the rf output on the k3 to some value below 12 watts. I have the same symptoms and thought it was the KPA500 but after disconnecting the K3S from the rest of the station I accidently determined that if I decreased the RF output to less that 12 watts the receiver is no longer attenuated. I am waiting until Elecraft is on a more normal footing before sending it back for repair. Marv KG7V -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Mark Goldberg Sent: Sunday, April 18, 2021 3:20 PM To: ws6x@gmail.com Cc: Elecraft Mailing List Subject: Re: [Elecraft] KPA500 Question Is the key line indication on all the time? This may be indicative of a stuck key line. There was an unsoldered resistor on mine causing the issue. 73, Mark W7MLG On Sun, Apr 18, 2021, 2:38 PM wrote: > I just purchased a used KPA500 (SN 0456) from a close friend. The amp > was just back to the factory for several repairs and was thoroughly > tested. The report reads, "KPA500 #0456 meets or exceeds all factory specifications." > My > friend unboxed the amp and made several QSOs to be sure all issues > were fixed. He then personally delivered the amp to my QTH. > Over the weekend I got the amp added to my operating position and was > quite surprised to find that input signals are attenuated > significantly when the amp is switched from STBY to OPER. No, this is > NOT the issue with having the aux cable and the PA key line connected > at the same time. This is with NO PA key, and NO aux cable connected. > The amp has no connection but RF input and output. It is independent > of band. This is with a matched antenna, band switched manually with > the front panel buttons. When I engage OPER the input signal is > attenuated by ~20 dB. > On the TX side, the amp is fine. On most bands I get full rated output > into a dummy load with approx. 20 Watts of drive from the K3. > I noticed on the service report, one of the tests was, "Tested receive > attenuation and IMD." I'm curious about "receive attenuation." This > would seem to be related to my problem. Looking at the block diagram, > I surmise something in the TR switch is malfunctioning. > Before I bug an already-overloaded Elecraft support, I am open to > suggestions. Am I missing something obvious? > TIA es 73, > Jim - WS6X > P.S. Yes, I have read the manual, and scoured the archives. The only > thing I can find regarding input attenuation in the OPER mode involves > incorrect cabling. > > __ > 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 > marklgoldb...@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 marvwhee...@nwlink.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 Question
Hi Jim, Sounds like an issue with the T/R circuit, you'll find some reports in the history of this list. I had a very similar case just one week ago - in my case it was R7 which was blown. The original type seems to be a 51 Ohm (type 1206 SMD) resistor - I've used now two 100 Ohm 1/4 watt resistors in parallel... Please check the diodes D8 and D9 if the resistor is ok - but in my case it was very obvious: At least I've seen the remainders of the SMD and not just a black spot (as others reported earlier)... Taking the PA apart and put everything back together took more time than the repair ;-) Best regards Tom, DL3DTH Am Sonntag, dem 18.04.2021 um 17:36 -0400 schrieb ws6x@gmail.com: > I just purchased a used KPA500 (SN 0456) from a close friend. The amp > was > just back to the factory for several repairs and was thoroughly > tested. The > report reads, "KPA500 #0456 meets or exceeds all factory > specifications." My > friend unboxed the amp and made several QSOs to be sure all issues > were > fixed. He then personally delivered the amp to my QTH. > Over the weekend I got the amp added to my operating position and was > quite > surprised to find that input signals are attenuated significantly > when the > amp is switched from STBY to OPER. No, this is NOT the issue with > having the > aux cable and the PA key line connected at the same time. This is > with NO PA > key, and NO aux cable connected. The amp has no connection but RF > input and > output. It is independent of band. This is with a matched antenna, > band > switched manually with the front panel buttons. When I engage OPER > the input > signal is attenuated by ~20 dB. > On the TX side, the amp is fine. On most bands I get full rated > output into > a dummy load with approx. 20 Watts of drive from the K3. > I noticed on the service report, one of the tests was, "Tested > receive > attenuation and IMD." I'm curious about "receive attenuation." This > would > seem to be related to my problem. Looking at the block diagram, I > surmise > something in the TR switch is malfunctioning. > Before I bug an already-overloaded Elecraft support, I am open to > suggestions. Am I missing something obvious? > TIA es 73, > Jim - WS6X > P.S. Yes, I have read the manual, and scoured the archives. The only > thing I > can find regarding input attenuation in the OPER mode involves > incorrect > cabling. > > __ > 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 thomas.kl...@gmx.de __ 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 Question
Is the key line indication on all the time? This may be indicative of a stuck key line. There was an unsoldered resistor on mine causing the issue. 73, Mark W7MLG On Sun, Apr 18, 2021, 2:38 PM wrote: > I just purchased a used KPA500 (SN 0456) from a close friend. The amp was > just back to the factory for several repairs and was thoroughly tested. The > report reads, "KPA500 #0456 meets or exceeds all factory specifications." > My > friend unboxed the amp and made several QSOs to be sure all issues were > fixed. He then personally delivered the amp to my QTH. > Over the weekend I got the amp added to my operating position and was quite > surprised to find that input signals are attenuated significantly when the > amp is switched from STBY to OPER. No, this is NOT the issue with having > the > aux cable and the PA key line connected at the same time. This is with NO > PA > key, and NO aux cable connected. The amp has no connection but RF input and > output. It is independent of band. This is with a matched antenna, band > switched manually with the front panel buttons. When I engage OPER the > input > signal is attenuated by ~20 dB. > On the TX side, the amp is fine. On most bands I get full rated output into > a dummy load with approx. 20 Watts of drive from the K3. > I noticed on the service report, one of the tests was, "Tested receive > attenuation and IMD." I'm curious about "receive attenuation." This would > seem to be related to my problem. Looking at the block diagram, I surmise > something in the TR switch is malfunctioning. > Before I bug an already-overloaded Elecraft support, I am open to > suggestions. Am I missing something obvious? > TIA es 73, > Jim - WS6X > P.S. Yes, I have read the manual, and scoured the archives. The only thing > I > can find regarding input attenuation in the OPER mode involves incorrect > cabling. > > __ > 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 marklgoldb...@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
[Elecraft] KPA500 Question
" When I engage OPER the input signal is attenuated by ~20 dB." I can detect no difference in received signal between OPER and STBY. This was for an "on air" test. I did not test with a signal generator. 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] KPA500 Question
I just purchased a used KPA500 (SN 0456) from a close friend. The amp was just back to the factory for several repairs and was thoroughly tested. The report reads, "KPA500 #0456 meets or exceeds all factory specifications." My friend unboxed the amp and made several QSOs to be sure all issues were fixed. He then personally delivered the amp to my QTH. Over the weekend I got the amp added to my operating position and was quite surprised to find that input signals are attenuated significantly when the amp is switched from STBY to OPER. No, this is NOT the issue with having the aux cable and the PA key line connected at the same time. This is with NO PA key, and NO aux cable connected. The amp has no connection but RF input and output. It is independent of band. This is with a matched antenna, band switched manually with the front panel buttons. When I engage OPER the input signal is attenuated by ~20 dB. On the TX side, the amp is fine. On most bands I get full rated output into a dummy load with approx. 20 Watts of drive from the K3. I noticed on the service report, one of the tests was, "Tested receive attenuation and IMD." I'm curious about "receive attenuation." This would seem to be related to my problem. Looking at the block diagram, I surmise something in the TR switch is malfunctioning. Before I bug an already-overloaded Elecraft support, I am open to suggestions. Am I missing something obvious? TIA es 73, Jim - WS6X P.S. Yes, I have read the manual, and scoured the archives. The only thing I can find regarding input attenuation in the OPER mode involves incorrect cabling. __ 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] WTB: 73CNC Knob for K3
Me again. Still searching for a very specific knob. This is a solid black knob with a non-spinning finger dimple. Heavy at 14 oz. Have gotten offers but they don't seem to come through. Appreciated. Ed NI6S __ 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] XV432
I would like to thank Don, Mike and Peter for responding to my plea for help for an XV transverter crystal oven. I never cease to be amazed at the help given on the Elecraft reflector which is second to none. Thank you gentlemen. 73 de David G4DMP In a recent message, David Pratt writes I am wishing to buy an XV432 transverter for use with my K2. If anyone has one which they no longer need, I would be pleased to hear from them. 73 de David G4DMP -- + - - - - - - - - - - - - - - - - + | David M Pratt, Kippax, Leeds. | | Website: http://www.g4dmp.co.uk | + - - - - - - - - - - - - - - - - + __ 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] WTB: KXPA100 preferably with KXAT100
Please let me know if your are interested in selling. Must be in excellent condition. Thx Eric KI5PCZ Sent from my iPhone __ 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
