432 MHz page


Because of my 144 MHz EME experience I wanted to become active on 70cm 432 MHz and needed more power than the standard 25 Watts from my Yaesu transceiver.
From the former Traxys network in The Netherlands I could do tests with some amplifiers which were used for 24/7 duty running 40 watts.
For SSB use I had to add a bias circuit in order to get correct performance. After the modification I tested the maximum power which was 100 Watts.
Because I had several of these amplifiers I eventually put 2 parallel using the Wilkinson power divider concept.
And I used one extra at the input to boost the input power and therefore it was not needed to run my transceiver at maximum power. The final result is about 200 Watts RF power on 432 MHz at 13 Volts and 30 Amps.
Some photo's of the testing and close-up of the bias circuit.

Testing 70cm amplifiers Bias circuit two parallel
input Wilkinson power divider power final result in 19 inch frame

With these amplifiers I worked OE5XBL. Next step is to try more tropo and EME contacts.


Home