[Elecraft] KPA100 operation - is this normal?
I noticed some things with the KPA100 that I wasn't expecting. Are these normal? 1. Power output fluctuated during a single CW TX session. I'll see the PO indicator on the K2 go up down by 1 LED on a frequent basis (maybe switching every few seconds). Thinking that I was right on the edge of an LED transition or something, I changed the power output level. The behavior continued at the new higher power level. I also see the output power on my outboard power meter change. The changes appear to be fairly small, maybe 10 watts at the 100 watt level. Is this normal? 2. Fan came on. My shack is a chilly 62 degrees F. I set the temp in the K2 per the instructions. During a CW QSO, the fan came on about 1/2 way through my TX session and stayed on for about 1/2 of the other guy's TX session. Power out was 100 watts, SWR is flat enough to not deflect the REV meter on the Palstar. The heat sink did feel warmer than the room but no way I'd say it was hot. Is this all normal or is there an issue? - Keith N1AS - - K2 5411.ssb.100 - ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] KPA100 operation - is this normal?
Darwin, Keith wrote: I noticed some things with the KPA100 that I wasn't expecting. Are these normal? 1. Power output fluctuated during a single CW TX session. I'll see the PO indicator on the K2 go up down by 1 LED on a frequent basis (maybe switching every few seconds). Thinking that I was right on the edge of an LED transition or something, I changed the power output level. The behavior continued at the new higher power level. I also see the output power on my outboard power meter change. The changes appear to be fairly small, maybe 10 watts at the 100 watt level. Is this normal? Yes, but there's a mod available to reduce the variation. See http://www.ac6rm.net/mailarchive/html/elecraft-list/2003-06/msg00550.html and http://www.elecraft.com/Apps/Power_Control_Mod.html 2. Fan came on. My shack is a chilly 62 degrees F. I set the temp in the K2 per the instructions. During a CW QSO, the fan came on about 1/2 way through my TX session and stayed on for about 1/2 of the other guy's TX session. Power out was 100 watts, SWR is flat enough to not deflect the REV meter on the Palstar. The heat sink did feel warmer than the room but no way I'd say it was hot. Is this all normal or is there an issue? Yes, I think so. See what others say. -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] KPA100 operation - is this normal?
Kieth, You can increase the value of R98 on the bottom of the RF Board to reduce the power fluctuation, but don't go so high that the power output on the higher bands is reduced substantially. Some experimentation may be in order. The fan may come on at strange times if the menu CAL tPA parameter is not set correctly. The manual tells you to set it to the room temperature in degrees Celcius - but there is a big dependency in doing that - the heat sink must be at the same temperature as the room. While the heat sink will eventually acclimate to the room temperature, it will take a bit of time. If you want to circumvent waiting for the heat simk to acclimate, you can measure the temperature of the heat sink itself and set CAL tPA accordingly. 73, Don W3FPR -Original Message- I noticed some things with the KPA100 that I wasn't expecting. Are these normal? 1. Power output fluctuated during a single CW TX session. I'll see the PO indicator on the K2 go up down by 1 LED on a frequent basis (maybe switching every few seconds). Thinking that I was right on the edge of an LED transition or something, I changed the power output level. The behavior continued at the new higher power level. I also see the output power on my outboard power meter change. The changes appear to be fairly small, maybe 10 watts at the 100 watt level. Is this normal? 2. Fan came on. My shack is a chilly 62 degrees F. I set the temp in the K2 per the instructions. During a CW QSO, the fan came on about 1/2 way through my TX session and stayed on for about 1/2 of the other guy's TX session. Power out was 100 watts, SWR is flat enough to not deflect the REV meter on the Palstar. The heat sink did feel warmer than the room but no way I'd say it was hot. Is this all normal or is there an issue? - Keith N1AS - - K2 5411.ssb.100 - -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.432 / Virus Database: 268.15.9/571 - Release Date: 12/5/2006 11:50 AM ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
