[Premium-Rx] Collins Mechanical Filters

[Greg Bailey]

I've been helping an aging ham clear out some of his old stuff - of which 
he has an astonishing amount! Most is not likely to be of interest to 
Prem-Rxers - but ...

There are three brand new Collins mechanical filters - military origin. 
They are one of F500Z11LSB, and two of F500Z10USB. These are - I think - 
500kHz IF LSB & USB filters.

Does anyone have a clue about the radio they would have been used in?

Greg