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« on: October 30, 2019, 2229 UTC »
i thought i was pretty much alone and misunderstood when i did the same thing as you, modifying a PLL controlled FM receiver with FM modulation "tapped" in the circuit by prodding around with line-level audio through a hi-Z cap until i got good modulation results and using the local OSC RF output as an "exciter" which could be further amplified down the line, i used the amplifier module from an "airplane" VHF transceiver with a home-made vertical dipole @ 87.9Mhz.
i did not have the capability to provide a true stereo signal but i did "tap and borrow" the 19Khz pilot tone from another receiver tuned to a local powerhouse FM station just to "appear" as stereo - back then in the 80's and 90's, it was better to "illuminate" the stereo indicator on ones receiver, there were many receivers back then that would "mute" a signal that was not in stereo anyway.
i fed a mono signal from a 4 channel radio shack mixer into a 2x6 EQ, left channel sloped from low to high, right channel sloped from high to low, fed each channel from the EQ into each channel of the AGC circuit of a Hi-Fi VCR deck and combined the output into mono, that was my "sound processor" and it worked pretty well.
the interesting part was using T180 cassettes in "EP" mode to record my shows, i have hundreds of them now, stored away, i used a full-size VHS camcorder to provide the video to "stabilize" the recordings (most VCR's cant record a stable audio recording without a video source).
in addition to having a two more VHS Hi-Fi decks which was used to play recorded VHS shows from others who wanted some airtime as well as playing my own shows, both VHS decks were wired together so when one program ended on deck 1, deck 2 started the next program, enabling me to run the station and have free time with friends - when the last program ended, a relay kicked in and turned off the TX amp (i used another 4 band EQ to the TX as FM pre-emphasis).
i had two "technics" turntables, two "pioneer" cassette decks, one CD player, one cardioid mic and two Hi-Fi VHS decks and hundreds of vinyl records, CD's and cassettes.
those were the "fun" days before the proliferation of the internet, MP3 players and satellite radio, i sure do miss those days.
i dont think i could ever do it again, it just wouldnt be the same today.
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