[Collins] filter id

[Dr. Gerald N. Johnson, electrical engineer]

The X250 and F250 probably indicate center or carrier frequency of 250
KHz, though that is LOW for a crystal filter. If the other filters don't
show center frequency and bandwidth on their labels, the only ways to
identify them are to find them used in a radio, find their Collins
specifications (takes a current employee), or search with signal or
sweep generator. There might be specifications in a Collins mechanical
filter catalog for the mechanical filter, mine isn't handy at the
moment.

I have a shoe box of odd crystal and mechanical filters, mostly labeled
with center frequency and bandwidth that I've collected from Collins
Surplus in years past. These could fit there, better than being thrown
out.

73, Jerry, K0CQ, Technical Advisor to the CRA.
-- 
Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.