R145 Redifon Receiver

R145 Redifon Receiver

Click to view block diagram in a new window.

Click to view detailed pictures of the receiver.

General Description

The R145 Receiver was produced by Redifon (U.K.) in 1959 for use by various government departments. It is a monumental piece of engineering excellence.

The set was specifically designed for high stability operation, with the oscillator having a stability of 250 cycles and the bfo 20 cycles. The set covers 2 - 30 Mc/s in fourteen switched bands of 2 Mc/s each. It is a single conversion superhet on 2 - 4 Mc/s and double conversion on higher bands. An optional sideband adaptor adds an extra stage of conversion when fitted.

This is a highly complex receiver. It is extremely heavy at 36.2 kgs (80lb) and needs to be mounted on a very rugged bench. If you put it on a collapsible card table it sure will! It is an excellent performer, with all the facilities of a high grade communication receiver. The sensitivity is better than 1uv unmodulated for a 14db signal/noise ratio. The set contains 24 valves and includes a mains operated power supply.

These receivers were reputedly used by O.T.C. and D.C.A. (Australia) often on RTTY links. Although it appears that these are SSB receivers, they are not by the current meaning of SSB. Rather than single sideband reception, the adaptor has the ability to select either sideband of an AM transmission, which it does to great effect. These sets are real collectors items if one has the space and lifting capacity!

Detailed illustrations of the receiver are shown on a separate page.

Back to Top or Go to Home page.

© Ian O'Toole, 2009. Page created: 25/11/06 Last updated: 4/12/2009