PS: I read in old Dutch Radio Bulletin magazines from the 50's that in the beginning of tv reception motors of mopeds frequently caused interference with reception of the Amplitude Modulated (AM) television screens. Which caused disturbing horizontal lines on tv screens in passing by any tv antenna. You probably know that television images are not transmitted as Frequency Modulated (FM) images because of the then much larger required bandwidth, why they are modulated in AM. Which normally only creates 2 in size limited sidebands, and makes it even possible to remove one of the sidebands saving power. Also still used by radio amateurs on Short Wave Bands (SSB modulation). Therefore in those years they obligated by law engine noise filters on mopeds.

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Thanks Mark!

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By-the-way: The dynamic microphone that was used in this FM PIEZO WX-172 wireless microphone transmitter measured 257 ohm on the 2k scale.

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Yes Imoudu, that was also what I thought when I noticed the badly condition of the rusted case compared to the nice looking pcb board. Afterwards all components were fine but not the corroded battery contacts and the case itself after the batteries must have leaked and had deteriorated the inside.

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Yes that was a great time Paris! In that time in the 80's most of those pirate music stations operated from Belgium. And I heard that also in my home town someone even was caught with a live tv pirate station. I myself however never saw that channel in action on tv, only heard about it and knew who that person was. But I also had built such a working VHF tv transmitter with in its endstage a 2N3866 transistor with only very limited rf output power. It was from an article in Dutch magazine Radio Bulletin.
And then came the release of the 27 Mc citizen band (Dutch: Bakkies) still at first only for 500mWatt RF power. It was great fun and also could be useful, but all of course before todays mobile phones existed. 27Mc probably was also released at that time because transmitting tv channels over cable instead of air made TV signal interference less likely. Especially in the event someone still used an illegal RF power amplifier to enhance his limited RF output.

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