In talks with Joachim, PA1GSJ we decided to build the simplest possible (construction wise) transmitter for 28MHz.
Using a "canned" - in my case IC-like housing - oscillator on 28.322 MHz and a 74HC(T)240 as the "power amplifier" it is possible to get an output of around 50 mW, sufficient for a QRSS MEPT.
Joachim already has his model working, and I am in the process of building mine. The oscillator is there (duh)and the "PA" is just about wired, now I need to make the keyer , will be using a PICAXE processor, and the output matching circuit/low pass filter.
QRP-LABS 5Watt PA - I am still struggling to make a "simple" 5Watt PA for the 1.8 - 50MHz range The QRP-LABS 5W PA could not deliver more then 1W at 28MHz using the original...
8 minutes ago