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Re: Mighty Mike Transmitter


 

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I don't see the feedback path to cause the crystal to oscillate.? If Q2 is supposed to be a Colpitts oscillator, it is not correct and missing the feedback capacitors from base to emitter and emitter to ground.? If you remove C1 and replace it with a 220 pF capacitor, and add a 100 pF capacitor from the base to the emitter it will probably oscillate.? You might have to experiment with the size of R3 to set the drive output of the Q2 circuit.

Hope this helps,

Jim, K8IQY

On 4/23/2025 6:25 PM, Steve Z via groups.io wrote:

I've begun building this transmitter (Manhattan style) but cannot get the oscillator to oscillate. Has anyone built this before? I also put the oscillator into LTSpice and did not see oscillation. Does anyone know if this will work?

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