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Argus25 · 15th Dec 2019, 8:11 am

I could point out that all of these types of designs are just "toys".

If you want a good Pantry transmitter it requires the following:

1) A power output stage with a proper impedance match to the antenna.
2) A crystal timebase, not just a drifting L/C oscillator.
3) A Linear Amplitude modulator.
4) A proper system of audio compression (AGC) to allow for the wide range of levels with different audio source material.
5) A system of audio soft peak clipping (with a visual indication) so that the carrier does not get over-modulated.

I have mentioned all this before with posts of circuits how to do it, but most don't bother and as a result most Pantry transmitters out there are pretty terrible quality.

15th Dec 2019, 8:11 am	#5
Argus25 No Longer a Member Join Date: Oct 2016 Location: Maroochydore, Queensland, Australia. Posts: 2,679	Re: AM Pine Board Project I could point out that all of these types of designs are just "toys". If you want a good Pantry transmitter it requires the following: 1) A power output stage with a proper impedance match to the antenna. 2) A crystal timebase, not just a drifting L/C oscillator. 3) A Linear Amplitude modulator. 4) A proper system of audio compression (AGC) to allow for the wide range of levels with different audio source material. 5) A system of audio soft peak clipping (with a visual indication) so that the carrier does not get over-modulated. I have mentioned all this before with posts of circuits how to do it, but most don't bother and as a result most Pantry transmitters out there are pretty terrible quality.