Here you will find the design of an Amplitude Modulated shortwave transmitter. (with roughly 4 Watts output on the desired frequency set by the crystal between 5.5MHz and 10.24MHz.)
All capacitors are ceramic type.
I use fixed mini-presets. You can also use external POTS for the Microphone/ Mixing controls.
(Use Preset in the emitter circuit).
The transmitter is suitable for A.M. voice purposes on the HAM band.
On the 7MHz Amateur Band, more then160 miles have been achieved using a 40mtr wire dipole antenna.
The 22pF trimmer aligns the frequency. The coils and the 47pf trimmer tunes for maximum output.
It is ideal to tune this circuit using a field-strength meter placed a few inches away from the transmitter.
Tune for maximum output.
When testing or operating this radio transmitter PLEASE DO MIND the legislation of the airwaves!
Success !!
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