Amp came with data sheets and basic guidance. It works, but bias does not seem to be temp compensated and standing current rose as the pallet warmed up.
Input VSWR isn't very good ( I swept it from 400-550MHz by which time is was around 2.5:1. Maybe the tiny trimmer capacitors (are they trimmers?? need a tweak to improve that.
But it amplifies as described....my pre-drivers are not linear or powerful enough to explore what it can really do, so I resorted to a well attenuated and under-driven brick amp. This woke it up and I think I was getting about 10W of DBV-T before I saw any regrowth. It got hot quickly at this level so I'll wait for fans to arrive. But 'good on paper', maybe someone with more knowledge can suggest improvements to the match and such. Both in and out have these small trimmers.
In terms of output, I was monitoring the output into a dummy load via a -40dB (possibly more at 70cms) coupler, and the trace went up 40dBm. The only 'power meter I have isn't rated for 70 cms (200MHz nominally) and it showed 10 watts.....
Gareth
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