Re: QRP PA devices for 10 GHz
Neil Smith G4DBN
HMC952A looks reasonable at around £37 plus tax at Mouser and £34
at Digikey in 10-off Cheaper from Arrow/Richardson RFPD, but
DK/Mouser deal with UK import VAT, saving customs fees. I just
bought ten in case they decide to go on back order adn 52 week
delivery, like some parts.
35 dBm saturated , P1dB 32 dBm, and over 30dB gain at 10368 MHz internally matched and with a power detector. Needs negative bias and interlocks for bias loss, overcurrent, and needs a temperature monitor. Power is +6V at 1400 mA quiescent and 2 A flat out. The PCB needs to shift heat well, the pad is 3 x 3 mm and needs to lose 10 watts, Thermal resistance is already pretty high, so cooling is a serious challenge, even if the PCB has lots of vias under that pad and it is soldered to a copper case or spreader.
There are still some gasfet devices around, but of the current crop of non-obsolete parts, this one looks to be best value. HMC487 is lower power, lower gain and double the price for no obvious benefit.
On 07/05/2021 21:36, Greg - ZL3IX wrote:
We've recently seen a couple of posts on this group about higher power (and expensive) PA devices, but what are guys using for the lower powers, maybe 0.5 - 2W? Are there devices around for a more reasonable price? I'm making fair progress with my home brew transverter for 10 GHz, and the next stage will be to produce a little power on the band. ideas?