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I have a Henry UHF Amp model C25D02, 1-5 watts in, 25 watts out. I've had if for over 20 years; it was given to me by a retired police chief from California. I had never used it because I didn't have a use for it. The tuned center frequency is 464 MHz with a 10 MHz bandwidth. Perfect for GMRS but unusable for 70cm ham radio. So now I have a use for it in my GMRS repeater. I mentioned it in another thread earlier today. It's perfect for my repeater because 5 watts is the minimum specified power setting of the Kenwood TK-805D I'm using as the transmitter. That will raise its duty cycle, although it's not bad at its current setting of 12 watts. The amplifier is rated 50% duty cycle mobile and 100% duty cycle in a repeater, at 25 watts output. I had no documentation on the amp. It is still a current model, so I was able to find some data on it from the Henry website. I decided earlier this evening to email the company and ask about Part 95A type classification, and also asked if I could get a manual. I received an email reply within the hour from Ted S. Henry. He assured me that it is indeed type accepted, and attached a pdf of the manual. Two thumbs up for Henry Radio!

I have a Henry 1-5 watts in, 25 watts out amp. Center freq is 464 MHz and rated bandwidth is 10 MHz. Henry doesn't specify 95a type acceptance, at least on their website. But here is what they do state: "Type acceptance: When used with type-accepted exciters - where applicable." I might end up using it in my repeater. I think I saw a comment on this thread or another one on the site to the effect of there being no point in using an amplifier because most mobiles output at least 25 watts anyway. Well, here's my point in considering its use: duty cycle. The transmitter in my repeater is rated at 25 watts, but only with a 10% transmit duty cycle. This is typical. I'm currently running it at ~12 watts for a higher duty cycle. If I add the amplifier, I could reduce the transmitter power to its minimum of 5 watts while doubling my overall output power. Running that amp at its full rated power is not a problem since Henry rates it at 50% duty cycle in mobile use, and 100 % in repeater use! I believe it too, because its heat sink is nearly 4 times the size of the sink on my 25 watt radios. There's another advantage to running an amp, too: I'm using spatial separation instead of a duplexer. With an amp, I can locate the receiver antenna near the repeater and the transmit antenna farther from the repeater. That means the line loss will be mostly on the transmit side. So I can locate the amp out there near the transmit antenna and just increase the exciter power to compensate for the loss. Kind of a reverse of how the serious VHF/UHF weak signal guys put a preamp at the antenna feedpoint to negate receive line loss.