"N Cook" ha scritto nel messaggio
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Another related piece of cobbled together test kit is a simple spectrum
analyser.
Take a TV tuner and a very basic scope display. Make up a sawtooth
signal generator and feed the ramp voltage to the X i/p and the tuning
Vt of the tuner and feed the tuner if o/p , high f rectified , to the Y
i/p.
For added
sophistication loosely couple the o/p of a TTL crystal oscillator to
the tuner for spot frequency harmonics calibration.

Thanks for your interesting infos !!!

I.