National AN/URR-27

The URR-27 is a VHF receiver from 110 MHz to 190 MHz. Manufactured by National in the early 50s, it was heavily deployed by the U.S. Navy on both surface and underwater vessels.  An interesting peculiarity of this receiver is the balanced RF amplifier and RF mixer.  This approach was chosen to avoid RF leakage to the antenna.
Page 1
Page 2
Page 3
Page 4
Page 5
Page 6

(Click on images to get high res)
(Extensive Water and Hammer Damage!!)






Last Update 5/5/2001