A 432 MHz High Power Amplifier with a GS35b

(C) DL4MEA 03/1998

Inner View of the Resonator

This Tube seems to work best - Dino Power

What length must I take  for the devil

D:  Diese Endstufe befindet sich zur Zeit im Bau und läuft noch nicht wie erwartet, daher nur vorab einige Bilder des Aufbaus. Die Kathodenverschaltung ist analog zu CT1DMK's 70cm-GS35b..

E: This amp is currently under construction. It does not work as expected, so here are just a few pictures from the construction. The cathode circuit is similar to CT1DMK's 70cm-GS35b..

25.03.98: Ok, its done... Yesterday I got the expected result. I drove it with around 100W and got 2kW out. Plate voltage was around 4kV and 1A current. Efficiency then is around 50%.
Here is a brief description:

The resonator is 200mm x 200mm cross section. The cathode part is 80mm high and contains an input circuit just copied from CT1DMK's, but not bent. You can see a photo of it in the description of the 144MHz-GS35b. The anode resonator is about 30cm high. With respect to the photo in the middle, the complete 10cm diameter part on the tube head (including cooler) is 125mm long.
The output is coupled with a 35mm disc at around 8mm distance, the tune capacitor is about 50mm x 30mm and about 10mm distance.

More tests are to be done in the next time.