ICOM-735 as a shortwave pirate transmitter?

[diegocollado]

Hello again, everyone!
First of all, thank you very much to all of the kind users that helped me on my previous post. I really appreciate it.

I found lying around an old ICOM-735 which was used mainly as a receiver. Since I am still looking forward to the adventure that pirate radio is, do you think it would be a good shortwave pirate radio transmitter? If so, what would be the easiest way of adding an audio input?

Thank you very much!
Best regards,
Diego

[CoolAM Radio]

Simple connection



Don't forget - when you're planning to do long broadcasts,
it's best to place extra "cooling fans" at backside transmitter.

Try with low carrier first - then open audio!
Beware of "overmodulation!"


André
CoolAM Radio - ShortWave
the Netherlands
http://jingleproductions.coolam.nl/

[TheRelayStation]

Simple connection



Don't forget - when you're planning to do long broadcasts,
it's best to place extra "cooling fans" at backside transmitter.

Try with low carrier first - then open audio!
Beware of "overmodulation!"


André
CoolAM Radio - ShortWave
the Netherlands
http://jingleproductions.coolam.nl/

while this method will work to get the sound content through the radio, it will not sound that good for a few reasons:
1) its an amplified microphone circuit, it needs to be brought down to line level impedance at 600 ohms or less.
2) the amplified microphone circuit in the radio itself utilizes audio filters primarily designed for speech between 200Hz & 3Khz; typically, audio frequencies below 200Hz and above 3Khz are greatly attenuated, attempting to "boost" these missing audio frequencies will always result in distortion.
it would be much better to locate the low-level modulator/RF mixer IC using a schematic diagram and feed your line level audio to that instead.
this procedure is just the start, there are several other modifications that are necessary in order convert an amateur radio to operate like a full-range broadcast transmitter especially if you want to broadcast on AM.