It’s kind of hard to cook those fets. If
it’s not shorted, it’s probably good.
It would take a pretty good static spike to
cook the gate.
Do you have 12V on the tab?
Your not seeing any current increase with
the bias pot?
You sure the voltage is making it to the
Take a close look at T1 and T2 and make
sure their installed correctly.
Transpose the ends of the windings and it
doesn’t work anymore.
Just going down the check list. This is
when having a ‘Scope saves a lot of time.
The diodes were good. 5.1V supply was
I think I cooked my IRF510 somewhere along the line.
Power out with the modulation pot at it's highest is 5-10 mW.
Bias pot doesn't make any difference to the output despite
the gate voltage. I did start fully CCW.
I think I'm getting a pretty good signal to the gate, but not
is happening at the output.
I'll replace the IRF510 and try again.
On 2/17/2019 8:41 AM, ajparent1/kb1gmx wrote:
Check to be sure you didn't put the zener
diode (d1) in backward.
FYI the crystal for the 5351 will age and move in frequency
so retest in a month or two.