Re: 50 Watt PA Rev. 2

George Korper


D5 is very low. 07 volts  D3 is .7volts. I Changed D5. No change. 
Maybe C16 is bad...I'll try changing it.. I never did like the way it is too large  Hi Hi. 

On Mon, Jul 13, 2020 at 12:55 PM Ronald Taylor <wa7gil@...> wrote:
George, that sounds right. Now, while in receive mode check the voltage drop across D3 and then across D5. Both should show 0.6 volts or so of drop. If that's good then the problem is elsewhere. All that's left of this part of the circuit are C1 and C16. You might want to check and make sure they are indeed 1 uF ... (105) just to be sure... Good luck...Ron

On Mon, Jul 13, 2020 at 9:23 AM ajparent1/KB1GMX <kb1gmx@...> wrote:
RX attenuated...  

Q3 and Q5 are RX switching, they only have DC and during RX.

The drain of Q3 should have near 0 volts (less than 1) during RX.
gate of Q3 should have More than 6V.

IF gate of Q6 is not at least 6V during RX check Q5 gate of
Q5 should be 0 Volts or very close to that.
If that is not true check what is wired to jack X2 (Keying) or
possible Q6 in wrong or has a shorted solder connection.

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