Commander HF-2500 impressions
I purchased a Command Technologies Commander HF-2500 right before the 2008 SSB Sweepstakes and wanted to share my thoughts on this amp now that I’ve had a bit more time with it. My previous amp was a Collins 30L-1 and it proved to be a great learning tool, but a poor amp for my needs. The high cyclic nature of a contest really puts a great deal of stress on an amp, and sadly, my 30L-1 just wasn’t up to the challenge of a 24 hour contest. For a casual QSO here and there it is a great amp, but is unreliable for any type of serious contesting.
During the SSB Sweepstakes, the amp performed flawlessly. I could not believe how cool it was after running for several hours straight. Since the contest I have made several other contacts with the amp and each time I received excellent reports on my audio and signal quality. The only drawback coming from the Collins grounded grid design is the warm up period required prior to being able to transmit. In a contest application is this not a big deal, but when tuning the bands for DX, it could result in missing a rare one. This is a comment I have seen many times, but in reality, I power up the amp when I turn on the radio, just in case I need the amp, it’s ready to go.
The amp is very easy to operate and after getting the initial settings for the Tune and Load adjustments for my station, tuning up is very quick. I would have liked an amp with auto band switching and auto tune, but those cost more money than I was willing to spend. The HF-2500 was purchased from W4MYA for $1.10 per watt versus $3.24 per watt for a solid state 1kW amp. For a considerable savings, I’m willing to put up with manually changing bands and tuning the amp. I just have to be diligent during contests to keep the amp tuned as I move up or down a band.
The construction of the amp is rock solid. The switches and knobs are designed to last with a tough rugged look and feel. The amp has two meters, one for gird current and the other that is switchable between plate voltage and plate current. I leave the second meter set to monitor plate current and monitor it and my power meter when tuning. I do wish the amp had SWR and power output metering, but I am willing to put up with using an external meter for these functions.
The amp features a blower to keep the tubes cool, and at times, the noise can be annoying. I have read several articles on modifying the amp with a temperature control switch for the blower to reduce the noise. I have considered doing such a mod, but that is just one more point of failure and the cost of replacing a tube is more than the amount the noise bothers me. It’s not overpowering, but it can be bothersome. The placement of the amp in the station increases my awareness to the noise since the exhaust is right next to my radio. If I move the amp to the left side of my desk, I doubt I would notice the blower noise.
Overall, I am very pleased with the Commander HF-2500 and would have no problems recommending it to anyone looking for a well built amp that loafs along at 1500 watts out. It is a welcome step up from my Collins 30L-1 and will get help me log many stations in the coming years. I have been told this is a very trouble-free amp and based on my experience so far, I believe it. I was looking for an amp I would have for the next 20 years and this seems likely to outlast me.