Jay,
You might try the following procedure. I found this to work if the Drake procedures won't.?
?
If C19 & C25 adjustment procedure above does not work, provide a pulse source?
and adjust C19 and C25 for minimum pulse noise level, preferably zero with?
the function switch in the NB position. Verify adjustment by turning the function switch?
from the NB position to the Normal position and verify operation.
?
For the pulse source, I use my Weller WLC100 Soldering Station. It has an SCR to regulate the heat and is very noisy. Remember that the 4NB works on pulse noise. It will not work, in most cases with power line-type noises.?
?
73's,
Mark, WB0IQK
