On 2/9/2017 2:08 PM, Michael Black wrote:
Collins used mechanical filters in their receivers, but not all
of them.

Collins introduced them in the 75A-4 and 51J-4 receivers back in
the early '50s.

Drake used a 50 KHz IF and tuned LC filters in their receivers up
until the mid '60s.

The alternative to Collins mechanical filters were multi-pole crystal
filters. Which was what everyone else was using.

One of the stranger things to come across was Henry Radio offered a
kit to install a Collins mechanical filter in the Drake 2B receiver.

Absolutely pointless, but it allowed you to win "dick waving" contests.




--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com