04-12-2008, 01:41 PM
Using one of those 1960's Heathkit sig gens with external AM worked wonders at a museum display a few months ago. One addition that I made to the set-up was a step-up transformer (1:4?) from the CD player output to the AM input. Distortion was surprisingly low and not detectable to the ear.
In a pinch I use a double balanced diode mixer (hp 10514) as a modulator- this arrangement gives you very low distortion but you are limited to about one milliwatt max. This comes in very handy when you need to generate a modulated IF or RF signal and you only have a CW carrier source and a separate audio source.
In a pinch I use a double balanced diode mixer (hp 10514) as a modulator- this arrangement gives you very low distortion but you are limited to about one milliwatt max. This comes in very handy when you need to generate a modulated IF or RF signal and you only have a CW carrier source and a separate audio source.
Pete AI2V
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