Not much info in the 1976 WRTH, but here is the pertinant stuff:

Selectivity: 2.5 and 5 kHz.
Sensitivity: AM 2 uV
CW/SSB 1 uV

Says that the shape factor of the filters is not good. There are images
and birdies.

There is an optional calibrator available, QR-6 MK, 500 kHz.

Steve
Holland, MI

Drake R7, R8 nd R8B

Thanks so much for the data! Its better than nothing...which thus far
is about all I've found myself. Thanks!!