If you really want to get into this posting, maybe it’s better to refresh your memory here.

So I bought the KPA-500 from what I still believe to be a trustworthy source. Hooked it up, tested it and it worked. At least: it sensed RF to track the band, and when keyed there was output according to the drive level. I was busy living life (kids, job etc) and ham radio was on the background, and I had had it with technology, parts, connectors and soldering. Enough troubles on my mind already. So I ordered the (too) expensive K3-to-amp cable because I wanted to have the amp track the K3 and create a hands off setup. And not spend time achieving it.

The first real test was the end of January: the UBA SSB contest. I used the KPA-500 for the exact purpose I bought it: give radio 2 some more punch than barefoot. The setup with cable didn’t really work well but I was too tired, too lazy and too much into a “can’t be bothered” state so I blamed the lack of RTFM and preliminary testing. The problem was a weird clicking sound in the amp when PTT’d and driven. It clicked in the headphones as well. Also there seemed to be a problem with the band tracking between K3 and amp. It didn’t work as advertised.

That problem returned in the ARRL CW and in the UBA CW contest where I used this radio more intense and so I reported it. The public Elecraft reflector remained silent on my topic so I turned to Elecraft support. As expected and as usual I got prompt reply and some hints. First of all they said they had seen faulty K3-to-amp cables in the past. The cable looks solid though and since it looks like a factory / machine made quality cable, I assumed the cable was OK. They had me open up the amp and fiddle with ribbon cables etc but to no avail. I was still busy, weary and going through the desert (i.e. a loooong dark energy slurping winter) so I could not be bothered with this device. I could not even be bothered with contesting. So it sat here for a few months. Untouched. Unused. I felt a bit stupid that I bought the amp. I was looking for some extra dB and not excessive power. My self imposed limit is 1500W. There is no RFI/TVI/neighbour complaining and nothing melts. Why push it? The OM-Power mini 1500W amp costs a few hundred Euro more than what I paid for the Elecraft amp (remember: it did NOT come as a bargain). I could drive that amp to 500W too but still have 1500W on the shelf if the main amp breaks. And have three year pick up and repair service warranty (if I’m not mistaken, but I seem to remember that).

Fast forward a few months to July 1st. Also my first day of summer recess. I decided to tackle the problem since the amp had to work and function. Be it here or somewhere else if I could ditch it. Ditching it would mean it had to work 100% anyway because you cannot sell something you know is broken. I picked up the email thread with Elecraft support and once again: no complaints when it comes to responsiveness. They still pointed out the control cable might be a bad one. I measured it through for connectivity and it seemed OK. But some pins were wiggling.

So I finally did what I wanted to avoid (but should have done!) in the first place: solder a K3-to-amp cable. Straightforward, a cable with ten wires, twenty hot kisses from the soldering iron. Twenty minutes later the K3 and the amp were talking to each other. It turned out to be a broken cable after all. In the end I bought two VGA connectors (M+F) and took a leftover end of control cable and twenty minutes later I had the equivalent of something that cost me about 80 Euros that can now be thrown into the bin. Oh my! Elecraft acknowledged this and has agreed to pay back the cost of the cable (minus S/H of course and the 21% VAT the greedy government stole from me). I still need to check back on how they will pay me back. It’s been two weeks and a half and not a word from the sales dept.

But the case is not closed. Yes the posh malfunctioning cable is now replaced with a simple homebrewed equivalent that does work. After all, my collegues in my previous life as a broadcast service engineer didn’t call me The Cable Guy for nothing! But the clicking and attempting band switching under TX remain. Back to Elecraft support. Again, prompt and thorough assistance. Check this, try that. The CPU keeps a fault log in EEPROM (flash?). If I could download that from the amp and mail to Elecraft? It turns out that early in its life the amp has been beaten up with excessive drive and reflective power / high SWR. It’s hard to tell exactly when because the amp has no clock and thus cannot track the exact time/date. But this power scam could not have happened here that’s for sure: no more than 2:1 SWR here and I don’t key the amp without a load.

Could that be the culprit? If so then the seller sold me a tortured unit. Or is the band switching when I’m transmitting caused by their faulty cable? The more emails I exchanged with Elecraft support, the more people were CC’d (engineers, developers, service techs, firmware coders) and the more it looked like the amp had to be sent in for repair.

The problem was that when transmitting, the amp acted like it sensed another frequency / band than what I was actually driving the amp with. So with PTT keyed and the amp driven, it wanted to go to 18.1 MHz. Except when on 18 MHz then it wanted to see 21 MHz. Then it sensed it was wrong after all and went back to the band I actually was on. When it happened, some relays clicked and this made my CW lose a few dits or dahs resulting in erroneous transmissions. It occurred always, sometimes after a second, sometimes after a few minutes. But no escape. Each time the amp acted up.
The first week of July I made 400 CW contacts like this. I left the Big Amp off and tested the KPA-500. I must say that apart from the switching and clicking, I liked it a lot. It renders the K3 into a 500W radio. Period. And that 500W seemed enough to break any pile up I engaged in (no real crazy ones P5-style) and I could raise some DX myself with it. The fact that this amp is so little and its integration with the K3 makes it an interesting medium power DXpedition combo. And it has 6m which the big amp doesn’t have. So I decided not to let it go and have it fixed.

Nothing left to do then than to pack it up and send it to the authorized service centre in Italy. Once again: quick and correct communication with the Italian guy running the repair shop. He told me to remove the large torodial transformer and keep that one here. This effectively cuts the weight in half. Have carrier pick up box and dispatch to Italy: 29 Euro. Three days later: amp arrives safe and sound in Italy. One week later: amp is ready, please pay 283 Euro (UPS return shipping included). Ouch. You lose some? You lose big time!

There was no cure mentioned. What was wrong then? Of course I want a detailed explanation of what was wrong and what parts they changed. But I cannot get more than this: ‘the microprocessor in the front panel was faulty’. How can this happen then? Overvoltage? Overheating? EMP strike? Or is it some I/O port that blew up? If so: could it be caused by the faulty Elecraft cable? I guess I’ll never know. So I just paid 283 hard earned Euros and hope this will cure the problem once and for all. Now I spent more money on the amp than if I would have bought it new in which case I would have been covered by warranty.

Now, to comfort myself, let’s put things in perspective. I’ve been a ham since late 1999. I’ve owned and still own quite some hi tech devices like rigs, power supplies and amplifiers. Then there’s the mechanically vulnerable setup outside: antennas and tower/rotator. What did I have to pay as repair costs over all these years?

  • Had both my TS-850 serviced and repaired by Kenwood. I seem to remember this was around 50-70 Euro each.
  • Blown Wimo ‘1 kW’ trap. Cost about 50 Euro, is a QRP joke inside despite the QRO label on the outside.
  • Blown WARC dipole. I paid this antenna 150 Euro and it served me excellent for over six years.
  • Mysterious problem with ACOM 1000 amp: cost me 250 Euro, took over three months to get it back, zero status update and each time I called the Belgian service centre myself, they pulled my leg and told plain lies. Me cross-checking their story with ACOM Bulgaria changed the tone on the phone  ;o)
  • Then there is my very first rig (TR-9130 VHF all mode). Can’t remember what I paid for it. I’d say 250? One day it developed so much bad solder joints that I decided to give up on it. Countless hours of soldering short ends of resistor leg through the many PCB through-platings! I just threw the rig away. I had a TS-850 in place waiting and I was about to take the Morse exam and trade my VHF call for an HF one…

With so much devices being worth so much money and spread out over more than thirteen years of intense amateur radio pleasure, I guess it’s not so bad after all. I paid much more to keep the car running over this period.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>