Hi Fred I agree lots of good amps and I have owned several 6 different ones they have ran from worked to excellent. My last 3 IMHO have been standouts the first a Yaesu VL-1000 used it with 3 Yaesu radios from FT-2000 (2) of them to a FTDX-5000MP and my K3 that amp was 4 yrs old when I sold it not a single problem.
Sold the 5000 and VL-1000 bought second K3 and a Alpha auto tune amp but only HF. A month later bought the KPA500 for the second K3 in the SO2R setup so I had a 6m amp again. When I bought the KAT500 if turned the K3 into a 500w radio like my Yaesu's and VL-1000 a kw radio. An amp designed for a radio can't be beat by a generic amp simple but the KPA500 does a good job with my other radios very well on my Icom and other radios. The Alpha will work with anything you hang on it, I do understand the weight factor. 73, Fred/N0AZZ -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Fred Carvalho Sent: Sunday, February 17, 2013 5:20 AM To: [email protected] Subject: [Elecraft] KPA500 vs THP HL-550FX Hi Roy and all I own a HL-550FX. At the time I bought it for DXpeditions the KPA-500 had not been released yet. Just to make the comparison fair, it does not take 5 minutes do reset after an alarm. You will need to turn it on/off and it will go to normal state again. Regarding the input power level, I guess it was pretty much a decision than a problem. THP inserted a 6dB attenuator in the input to lower the amplifier's gain. So, even if you run close to 100W, you will be ok. BTW, the amplifier was not meant to be driven with any specific exciter, so the choice was probably to make it match FCC's requirements regarding PA's gain as well as to allow it to accept anything in the input without reducing too much the exciter's power. By bypassing the attenuator, one would need much less power to run it and would get more output power too. There is at least one advantage for those that will cross the world with it in airplane cabins. The THP weights 22.5Lbs against 26Lbs of the KPA500. It seems not too much, but after 28 hours carrying it in flights and airports, it will make a difference. Some international airlines weights the hand lugage. So lighter the better. I guess both products are in the good quality teams, but t you'll get more features and power for a $ spent with the KPA500. Regards -- Fred - PY2XB *Other Calls*: PY2FXH, PY2FXH/W2, PY2XB/0, F/PY2XB, ZX2XB, PT7BXB, PY2XB/PY0F, PQ0F, VP5/PY2XB, PW2IO (SA-071), ZX8W (SA-060), PY2XB/1 (SA-029), 8P9XB, PQ8XB (SA-045), ZX2S (SA-028); W4/PY2XB, 3D2XB *Team member*: PW2M (SA-071), PX8J (SA-041), T30PY/T30SIX, PT0S ______________________________________________________________ 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 ______________________________________________________________ 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
