23 cm ATV Transmitter
This is the box containing video pre-emphasis and the audio FM
modulator at 6Mhz.
The transmitter uses a modified ALPS VCO normally running at
950 MHz and after modification of the internal ceramic resonator (using a short
coil in parrallel with the resonator ) to bring it to 1275 Mhz.
This is a look on the bottow where you can see the VCO and the BFQ68 final
transistor.
Output power from this driving module is about 1.2W
This shows you how microstrip chokes and tank circuits are used.
The final PA build with a hybrid module increases power to
about 18W at 23cm
The output of this PA goes to my 25 element home made loop yagi ,about 20 m
above the ground.
