GROUND RADIO BULLETIN NO. 15 - SEPTEMBER 29, 1949 COMMS. DEPT. L.A.D.
51N-2 REMOTE CONTROL
The 51N-2 remote control systems have been Installed as in GEN-3A-816-2. This drawing shows the RF gain of the receiver being controlled over a phantom circuit using two 94E repeat coils. With this type of circuit, a good ground connection between the receivers and the control point is not required when' the receiver is used for phone reception. When the receiver is used for CW, however, loud signals may sound as though the receiver is blocking, although the actual cause is the inability of the 1.0 MFD condensers to carry all the audio output resulting in voltage variations in the receiver RF circuit. When a good ground between the receivers and the control point is available, better control may be had by using a simplex circuit to control the RF gain.
To do this, it is necessary to change the transformer connections. Referring to the functional diagram, GEN-3A-816-2, the 94E repeat coil (receiver end) terminals 1 and 6 are tied together and connect to the receiver RF terminal 7« No condenser or ground is used. At the control end the 94E terminals 3 and 8 are tied together and go to ground through the gain control. No condenser is used here. We are considering installing a small terminal strip on future models so that the type of control used may be selected with a jumper wire.
INSTRUCTION BOOKS
We now have available new part lists with up-to-date part numbers for the instruction books of transmitters, receivers, etc., which we employ. One complete set of these lists is being sent to each station. Additional copies can be supplied upon request from the DCS office.
FORM 9211—2107
