Although I’ve been using an Icom IC-9100 very successfully for the past 9 months or so, the urge to complete my DXCC this sunspot cycle is growing stronger. I’ve managed about 70 countries so far, but only have confirmation from 47. I heard that participating in DX contests is a good way to snag a few more, so I plan to join the horde in February.
To be a bit more competitive, I decided to add an amplifier. I’ve always thought Elecraft made excellent equipment, and figured someday I might wind up with a K3, so I started thinking about using a KPA-500. When I discovered several other IC-9100 users were using the KPA-500, that sold me.
I decided on the kit form and found it to be quite simple to assemble. The hardest part is sorting out all the hardware and making sure everything is there. That took about an hour. I spent slightly less than 5 hours putting it together. I was very impressed with the PCB assembly quality. Hole registration was great, as well as part alignment and solder quality. Where there were mechanical connections, gold plating was used. The boards were generally free of any rework (cuts/jumpers) and I only noticed a few caps that appeared to be hand soldered.
Beside the absolutely massive power toroid (it weighs about 15 pounds) the other surprising thing was how tiny the amp is. But it is very densely packed inside.
So far, with limited testing, things are working very well. It takes a bit under 20 watts to produce 250 watts of output, and about 35 watts to bring it up to the full 500 watts of output. Band switching is automatic and is based on sensed RF, plus the built in bar-graph power and SWR meter are a joy to use, and they continue to work even when the amp is bypassed.
So far all my tests have been on a dummy load, but the fan seems to take a long time before it turns on, ranging from very quiet to pretty loud. However, being fully automatic, there is no reason the amp can’t be tucked out of the way to reduce the sound of the fan.
Elecraft KPA-500 Amplifier
