Don:
Thanks. Yes, I know what that is for. Without it when you work a
repeater, sometimes on returning form transmit back to receive, the
receive frequency jumps to the transmit frequency. As I recall the
problem is caused by transient drops in the voltage at that point as a
result of T/R switching. I put in this mod and it fixed the problem for
me. I put in a 4.7 uf cap. I when I heard about the mod, the value
mentioned was 1 to 4.7 uf.
73,
Bob WB2VUF
Don Bullard wrote:
Bob,
The capacitor is a 1uF, 50V electrolytic. It jumpers across resistor
R32 (10k) with the positive end going toward Q8. R32 goes from ground
to the base of Q8. Maybe it extends the reset signal to U4?? Not sure.
I would be interested in details on the other cap you added to reduce
the CTCSS level. Thanks!
73,
Don W4IML
Don:
I'm curious. Where in the circuit did they add the capacitor and what
was the value of the cap? I might be similar to the capacitor that I
added to my 1220 to cure the excessive CTCSS tone level.
73,
Bob WB2VUF
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