Transmit Mode

the FREQ SELECTION line as explained in paragraph 1-16. Received audio passes to the front panel and is routed to

the internal speaker and the handset earphone. If the speaker is turned on, the incoming signal is heard through it and

the handset. If the speaker is turned off. the message is routed through the RCV AUDIO line to the handset earphone

where it can be heard only by the operator.

1-18. Transmit Mode

The transmit mode is enabled when power is applied to the radio and the handset PTT switch is pressed. When the

switch is pressed, it generates the PTT signal. After passing through the front panel. PTT is applied to the transmitter

and turns on the necessary transmit circuits. PTT also switches the transmit/receive switch to the transmit position. As

soon as the push-to-talk switch is pressed, the radio is ready to transmit the operator's message. When the operator

speaks into the handset microphone, the XMT AUDIO line carries the voice signal through the front panel to the XMT

AUDIO line and the transmitter circuits. The message is transmitted on the frequency selected on the front panel rotary

push-button switches. This frequency was programmed into the transmitter circuits by signals on the FREO SELECTION

line as explained in paragraph 1-16. Outputs from the transmitter are passed through the XMT SIGNAL line, the

transmit/receive switch, and the UHF/VHF switch. Depending on whether a UHF or VHF frequency was selected, the

UHF/VHF switch

1-19