Hello,
I have problems with a voltage tuned 29Mhz xtal oscillator, it has no output signal. Checked the bias of the transitor, all ok, replaced thre transitor, varicap and the x-tal, still the problem exist.
It can be a component that went out of spec. I do not have schemtics but tried to drow the wiring of the oscillator and it is attached. also, desoldered all the caps and took there value by a capacience meter, but values below 20pf can not be measured.
My first question, does this circuit represent a complete 29Mhz Oscillator ? the reason I am asking is that I could have missed other components on the curcuit board beloging to the oscillator. L1 is 560nH.
Description of the circuit:
Input power is 10V
Bias input isalways -5.2.
Tune voltage is 3.72V when the instrument is powered on.
Any hints what I can do or test?
Thanks
George
I have problems with a voltage tuned 29Mhz xtal oscillator, it has no output signal. Checked the bias of the transitor, all ok, replaced thre transitor, varicap and the x-tal, still the problem exist.
It can be a component that went out of spec. I do not have schemtics but tried to drow the wiring of the oscillator and it is attached. also, desoldered all the caps and took there value by a capacience meter, but values below 20pf can not be measured.
My first question, does this circuit represent a complete 29Mhz Oscillator ? the reason I am asking is that I could have missed other components on the curcuit board beloging to the oscillator. L1 is 560nH.
Description of the circuit:
Input power is 10V
Bias input isalways -5.2.
Tune voltage is 3.72V when the instrument is powered on.
Any hints what I can do or test?
Thanks
George
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