Correct...
Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ email: [email protected] -----Original Message----- From: [email protected] <[email protected]> On Behalf Of Mike Fatchett Sent: Thursday, March 3, 2022 6:31 PM To: [email protected] Subject: [POSSIBLE SPAM] Re: [Elecraft] FW: KPA500 faults St. Lucia is 240v. I don't know why he would run it on 120v or 110v. W0MU On 3/3/2022 1:39 PM, Naumann, Robert, W5OV wrote: > Bill, > > Thanks for the additional information. > > Can you tell us if you are running it on 120v? > > -Bob W5OV > > > -----Original Message----- > From: Dr. William J. Schmidt <[email protected]> > Sent: Thursday, March 3, 2022 10:40 > To: Naumann, Robert, W5OV <[email protected]>; [email protected] > Subject: RE: [Elecraft] FW: KPA500 faults > > Sorry guys, this is not a trivial line voltage problem. > > The 60V line to the PA does not sag that much (starts at 72V goes to 60V > under FULL LOAD as measured at the PA)... it's in the voltage divider for the > 60V/32 line or the connectors that carry it to the front panel processor for > digitizing. Changes with heat load. This amp is in the Caribbean and there > is plenty of excess heat and corrosion. (nb. I just replaced the current > sensing resistor in my K3S for the 100W module due to a hair-line crack... > surmise it was heating). > > > Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ > PJ2/K9HZ VP2EHZ > > email: [email protected] > > > -----Original Message----- > From: [email protected] > <[email protected]> On Behalf Of Naumann, Robert, W5OV > Sent: Thursday, March 3, 2022 9:11 AM > To: [email protected] > Subject: [Elecraft] FW: KPA500 faults > > > What line voltage are you running it on? If you're not on 240v, switching to > 240v would be the easiest and most effective improvement. > > Doing so yields a 4:1 improvement in line voltage regulation / reduction in > voltage drop. Double the voltage, at half the current draw. > > 73, > > Bob W5OV > > -----Original Message----- > From: [email protected] > <[email protected]> On Behalf Of Dr. William J. Schmidt > Sent: Thursday, March 3, 2022 00:39 > To: [email protected] > Subject: [Elecraft] KPA500 faults > > I have a KPA500 that faults on low (60 VDC) voltage. After measuring the > power supply voltage at the PA module is perfectly fine. The voltage read by > the processor on the front panel via pin 10 of P1 is lower than it should be > and hence the fault condition. I suspect there is a voltage divider on the > LPF board that drops the 60 VDC to something that the processor can read and > digitize (in the 0 to 3-5 volt range). The set of schematics I have do not > show the voltage divider anywhere. does anyone have this part of the > schematics for the KPA500 so that I can adequately troubleshoot this amp and > get it on the air for the contest this weekend? Multiple notes to Elecraft > have gone unanswered. > > > > > > Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ > PJ2/K9HZ VP2EHZ > > > > > > email: <mailto:[email protected]> [email protected] > > > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > [email protected] > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > [email protected] > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
