My new U3S is online :-)
I build my own 5-band version of G0UPL famous U3S kit kit. I placed it in an BOPLA ULTRAMAS cases.
The powersupply is a cheap chinese step-down-converter for the 5VDC rail of the U3s. For the PA power I used a LM317 based variable linear regularor.
The U3S with one PA FET gives the following output power:
The power readings are from home-build RF powermeter.
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