User's Manual
TECHNISONIC INDUSTRIES LIMITED
www.til.ca
TFM-550 Installation & Operating Instructions TiL 99RE262 Rev A Issue 8
1-1
SECTION 1 - GENERAL
DESCRIPTION
1.1 INTRODUCTION
This publication provides operating and installation information on the TFM-550 Transceiver
manufactured by Technisonic Industries Limited. The unit offers an extended frequency range
with selectable channel spacing and is intended for use (in the U.S.) only by government
agencies or contractors thereto, who have obtained licensing for operation in the 138-150 MHz
portion of the VHF band. If the TFM-550 transceiver is used in CANADA, VHF operation is
restricted to the following sub bands: 138-144, 148-148.99, 149.005-150.005 and 150.05-174
MHz. The UHF band is only authorized to operate in the following part 90 mobile and land mobile
frequency bands:
406.1 – 410.0 MHz 456.0 – 460.0 MHz 467.7375 – 470.0 MHz
410.0 – 420.0 MHz 460.0 – 462.5375 MHz 470.0 – 512.0 MHz
450.0 – 454.0 MHz 462.7375 – 467.5375 MHz
It is a violation of FCC rules if the device operates on unauthorized frequencies.
Do not use the TFM-550 in the frequency band 406.0 MHz – 406.1 MHz. This frequency band is
reserved for distress beacons.
Furthermore the TFM-550 is a frequency agile transceiver which is restricted to airborne use and
must not be operated as a base station in Canada.
1.2 DESCRIPTION
The TFM-550, Transceiver is a frequency agile, fully synthesized airborne FM transceiver
capable of operating in the 30 to 50 MHz, 138 to 174 MHz and 403 to 512 MHz frequency range
in 2.5 kHz increments with either 25 kHz or 12.5 kHz channel spacing. The Transceiver can
operate without restriction on any split frequency pair in either band.
The TFM-550 Transceiver provides 200 operator accessible memory positions per band, each of
which is capable of storing a transmit frequency, receive frequency, transmit frequency CTCSS
tone or DPL code, receive frequency CTCSS tone or DPL code, an alphanumeric identifier for
each channel and wideband (25 kHz) or narrowband (12.5 kHz) channel spacing assignment.
Operating frequency and other related data are presented on a 96 character, four-line LED matrix
display. Data entry and function control are performed via a 12 button keypad. Preset channels
may also be scrolled and scanned (scanning only possible in VHF high and UHF bands) through
keypad function activation. Data may also be entered via computer with the provided software
and optional PC Up/download cable, P/N 993390-1.
1.3 PURPOSE OF EQUIPMENT
The TFM-550, VHF High/VHF Low/UHF Band FM Transceiver is designed to provide secondary
airborne communications to facilitate operations which are typically performed in a low altitude
environment. The transmitter sections of this unit have a minimum of 8 watts and do not exceed
10 watts output power, which may be reduced by a front panel switch to 1 watt, in order to reduce
interference to land based systems.
1.4 MODEL VARIATION
There are four variations of the Model TFM-550 Transceiver. All units offer identical features and
performance except for the following differences:
TFM-550, P/N 991095-1 GREEN display and 28 Volt back lighting.
TFM-550, P/N 991095-1 (5V) GREEN display and 5 Volt back lighting.