[ARC5] RU-16 Versus RU-18

[Mike Morrow]

Wayne asked:

> Okay I know that has been discussed before, but will an RU-18 coil set
> fit an RU-16?

Yes.

Receivers (CBY-46036, 46041, 46046, CBY/CW-46048*, 46051*) from the 1932 RU-3 through the 1941 RU-19, plus the 1934 RAJ, all use the same coil set design.

The only exception are 1938 and 1939 RU-8, 9, 15 (CBY-46064).  That receiver (and also the RU-2A CBY-46012A) uses a ganged main tuning capacitor providing a nominal 2 to 1 high-end to low-end frequency span for each coil set, just like all of the SCR-A*-183/283 receivers.  All the other RU/RAJ receivers have a tuning capacitor providing a nominal 1.5 to 1 
coil set frequency span.

The differences between the RU-16/17 CW-46051A command set receiver and the RU-18/19 CW-46048D liaison receiver are due to the two-receiver design of the RU-18/19 system, which required differences in the AGC bias and AF stage power circuits, and transmitter sidetone input.

Mike / KK5F