Re: "Fuzzy" FM
For a simple answer to the 'wobbulator'/sweep generator problem, a cheap solution could be a simple one transistor oscillator - based on an old 10.7MHz IF transformer, perhaps.
For the sweep, remove the varicap diodes from a scrap UHF tuner, and either apply the sawtooth from the oscilloscope's timebase or use AC to drive both the scope and the oscillator. The maximum rating of the diodes is nominally 28V, so a 6V transformer - ~17V pk- pk (variable for sweep width) superimposed on 0 - 9V from the transistor supply, for centre frequency adjustment, would work.
Obviously, further discussion would be best in another thread elsewhere, but I'm throwing the idea out here as it is relevant to what has been said in this thread.
Perhaps somebody has already done something similar?
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