Instruction Manual

2-1
Audio Input 50 mV at 2.5 KHz into
200 S input circuit for
±3.5KHz deviation, adjst.
Audio Distortion Less than 5%
SECTION 2
OPERATING INSTRUCTIONS
2.1 OPERATING FEATURES
The Technisonic TDFM-136 airborne FM transceiver is visually similar to the industry standard TFM-
138, a two line by 24 character display is centered at the top of the unit, just below the display are
six user controls on the left and a 12 key keypad on the right (refer to Figure 2-1). The TDFM-136
support the following features:
1. 150 memory positions which can each be programmed with a transmit and receive
frequency with 25 or 12.5 kHz analog channel spacing, Tx/Rx CTCSS tones or DPL
codes and a 9-character alphanumeric title. Or the memory positions can be
programmed to P25 Digital mode (12.5 kHz) with or without a P25 Talkgroup.
2. 2 guard channels which can each be programmed with a Rx frequency with 25 or 12.5
kHz channel spacing, CTCSS Tx tone or DPL code and a 9-character alphanumeric title.
Or either guard channel can be programmed to P25 Digital mode (12.5 kHz) with or
without a P25 Talkgroup.
3. Scanning of programmed memories with selective memory scanning, in 5 scan lists.
4. Priority scan of memory channel 1, if desired.
5. Direct frequency entry mode.
6. Receive frequency simplex function.
7. Switchable RF output power between 1 watt and 8-10 watts.
8. Lockout of keyboard to prevent inadvertent entries.
9. Variable frequency mode to manually scan up and down in 2.5 kHz steps.
10. LED display variable dimming mode.
11. Selectable 90 second Tx time out feature.
12. Quick download of any of the 150 memory positions to the guard memories.
13. PC Memory Upload or download capability.
2.2 OPERATOR CONTROLS
The user controls comprise a main volume control – with integrated on/off switch - a guard volume control,
a squelch defeat button, a MAIN/GD selection switch, a GD1/GD2 selection switch, and a high/low power
switch. The keypad layout is a 3 by 4 matrix, the layout being similar to a telephone keypad, though the
options are arranged differently.