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Old 08-26-2022, 09:09 AM
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Notimetolooz Notimetolooz is offline
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Location: Dallas, TX
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I didn't want to interfere in the effort but I took a look at the Leader LGC-396 manual and it does not mention a 1KHz sound signal.
If it did that could be used to get the discriminator at least in the ballpark.

The way a NTSC RF signal is produced is that the sound signal (1KHz lets say) is FM modulated onto a 4.5MHz carrier, then that sound (sub)carrier is added to a video signal, that combined video signal is AM modulated onto a RF channel frequency carrier. The result is that there is a FM sound subcarrier that is offset from video carrier by 4.5MHz.

Do you have an oscilloscope?
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