I have several old radios here and thought a signal generator would be a nice Arduino-ish project to help alignment. This is the result:

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I used a breakout board with Si5351 and TCXO from Etherkit.com. My unit brings out all three signal outputs, individually programmable for frequency (500 Khz to 160 Mhz), sweep width and limited level control. There is a Teensy LC for control using Si5351 libraries from Jason Milldrum NT7S. The battery and charger are out of a cheap cell phone booster.

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