Kenwood TM-641A Instruction Manual

Also see for TM-641A: Instruction manual Service manual

4-3. TRANSMITTER OPERATION4-3-1. TransmissionCAUTIONS1. Ensure that an antenna with a low standing waveratio (less than 1.5 SWR) is attached to theantenna connector before attempting to transmit.Failure to provide proper termination may resultin damage to the final amplifier section.2. High-power and extended transmission increasesthe unit temperature.NOTE1. Always check to ensure the frequency is clearbefore transmitting.wr. Press the BAND SEL key for the desiredtransmission band. The PTT indicator will light forthe corresponding band. Bands in which the PTTindicator are not lit are used for reception only.(Example: 440 MHz band). Select the desired operating frequency .. Press the PTT switch. The ON AIR indicator willlight, and the RF meter will light.4. Speak into the microphone. The recommendeddistance to the microphone is 5 cm (2 inches).NOTETalking closer may result in over deviation of yourtransmit signal, which might be reported as a lossof clarity or an excessively wide transmit signal.Talking too far away may result in reports of weakaudio.5. Release the PTT switch to return to the receive mode.The ON AIR indicator should go out, and the RFmeter will return to zero.Simultaneous reception on the other bands is possibleduring transmit.NOTESome combination of transmit and receive frequenciesmight cause a reduction in receiver sensitivity.4-3-2. TX. AlertDifferent beeps can be heard for each band by pressingthe PTT switch. These signal which band you aretransmitting on.Press the PTT switch while pressing the F key.The TX alert function is then turned on or off.27