Greetings to All!
Is there, by any chance, anybody out there in T-T Land who has their
(working normally) Omni VI opened-up & could maybe take a couple of voltage
readings for me for check purposes?
I need the readings (with respect to ground) on pins 1, 2 & 3 of U1(A) -
which is a LM358 on the 9mHz Mixer/IF Board (81594). My Omni VI still shows
a full-scale reading on the panel meter, with meter switch in FWD position,
on receive. I'm beginning to suspect the LM358, on which my pin 1 reads 7.7v
pin 2 reads 7.0v
pin 3 reads 0.0v
all readings on cw receive.
The supply to this i.c, pin 8, reads 9.4v & I'm guessing that maybe an
internal breakdown is putting the 7.7v onto pin 1, which translates to 7.0v
on pin 2 via D24, but would really like a little reassurance from a better
brain before I pull the i.c and try another one!
Any ideas please folks?
73 de Mike, zl1mh
Oh, btw, readings on the other pins of the i.c all seem to be what (I think)
they should be.
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