@Pieritz: When you ask about the sensitivity of used MOSFET, do you talk about as modules or single MOSFET?
The Greek modul use an IRF640 and the German use two types RD06HHF and RD16HHF, here you must 'Google' the datasheets.
If you talk about as modules, the Greek has about 27dB. at 28V. Look here:
http://www.rfsource.gr/files/PM62FDC.pdfThe German has 30 dB Gain at 13.5V, 10mW in, 10W out (P/P):
http://www.qrpproject.de/UK/qrppa2008.htmlMy setup: 'Home made Exiter --> QRP-PA2008 (inside the exiter) --> PM62FDC' --> SB1000 --> 1 kW P/P (250W AM).
The Spitfire: One of my friends has a Spitfire and I will ask him about he has a diagram, but i think it has a kind of LP filter there adjust to a '3 meter wire', so the output impedance is 'unknown', but if he has a diagram, I will see what there can be done so it works as 50 Ohm.
Best 73 Ole

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