National NC-300 question

Schichler, Alfred ASchichler at MICROWAVEDATA.COM
Wed Feb 22 10:22:12 EST 2006

I was wondering if anyone out there is familiar with the normal operation of
the NC-300.

I recently bought an NC-300, and have restored it so it is working pretty
well and calibrated, but I'm not sure if the crystal filter is aligned
correctly or working exactly the way it is supposed to. 
The phasing control variable cap was cracked when I obtained it, so I had to
glue it back together and align the plates so they don't ever touch each
other. Now I'm not sure exactly where the capacitor is supposed to be
positioned when the phasing control is in the middle position, since I had
to take it all apart and put it back together again. 
I think I have it adjusted pretty close, but the resonant frequency seems to
be slightly different in each of the different selectivity positions. Also,
the signal strength seems to be quite a bit higher with the crystal filter
switched in the circuit compared to being in the "off" position where it is
switched out. Is this normal, or is there maybe a cap that has changed value
or something like that?

Thanks for any help,
73, WA2AS

The information contained in this message is confidential and intended only
for use of the designated recipient(s) named above.  If the reader of this
message is not the intended recipient or an agent responsible for delivering
it to the intended recipient, you are hereby notified that you have received
this message in error, and that any review, dissemination, distribution,
copying, or alteration of this message is strictly prohibited.  If you have
received this communication in error, please notify the originator
immediately and remove it from your system.

This list is a public service of the City of Tempe, Arizona

Subscription control -
Archives -

More information about the Boatanchors mailing list