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BC109C Oscillator Issues

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holmesat21

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I made a BC109C circuit on spice that runs but my physical design doesn’t run. I was wondering if anyone sees an issue with this design I have shown.
 

Unusual low LC circuit impedance. How did you arrive at the LC values?

Did you assign series resistance to model Q values according to inductor datasheet in your simulation?
 

I think you have a bunch of an unused 100nF capacitors in your drawer...
Replace L7 with 5uH, and R3 with 1.5k, and you will get the oscillation.
 

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Unusual low LC circuit impedance. How did you arrive at the LC values?

Did you assign series resistance to model Q values according to inductor datasheet in your simulation?
They’re hand wound inductors. I chose .507 as it was just the easiest to wind. I knew it had something to do with the tank but really just wanted help in case it’s the biasing or something dumb like that
 

I think you have a bunch of an unused 100nF capacitors in your drawer...
Replace L7 with 5uH, and R3 with 1.5k, and you will get the oscillation.
With spice you still get the oscillation with the given values but they’re at the desired frequency (1MHz) I can try this solution to see if it works but it would take some time to wind that inductor and ultimately it wouldn’t be what I want it at.

Can you explain why R3 would be better at 1.5K rather than 15K?
 

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