[Hammarlund] Why 2nd RF stage?

[Kenneth G. Gordon]

I just thought of two other reasons for two RF stages:

1) To eliminate any HFO feed through back through the antenna. The Navy 
was very particular about this, especially during WWII. National had to 
add a second RF amp stage to the RAO (NC-100) to meet Navy specs on this. 
And the Scott receivers were all designed specifically to reduce this to 
a very low level. Although it was never proven that the enemy ever used 
the re-radiation of the local oscillator of a receiver to DF a target, 
the Navy made sure it never could happen.

2) The second RF stage, especially when biased to a gain of 1, helped to 
prevent front-end overload products from getting to the mixer stage. The 
added selectivity at RF made the difference.

The OT designers weren't stupid, despite not having 'pooters at the 
time...

Ken W7EKB