FMTR151R
151MHz Transceiver

Description

The FMTR151R transceiver is a 151MHz half-duplex radio data module. With a RF power output of 100mW combined with its light weight and compact size, makes it suitable for long distance mobile applications. Applications such as wireless communications, radio remote controls, telemetry or wireless security systems is most suitable for the FMTR151R transceiver.

Data rates from 300 to 4800 bauds can be transmitted and received.

Transmit Mode

When the enable pin is high (+5Volts) the transceiver goes to transmit mode. In transmit mode, when an input signal (Data) is fed to the TX Data pin a FM modulated signal is transmitted directly through the antenna output terminal (Sh A Sh) block. A suitable 151MHz antenna should be connected to this terminal block. We recommend the Elsema ANT151, 151MHz antenna.

Transmit mode should be disable (TX enable pin to 0 Volts) to avoid unnecessary transmission if no data is on TX Data pin. This also enables the receiver which puts the transceiver into the receive mode.

For technical specifications on the transmitter refer to the T15105 radio data module.

Receive Mode

When the transmitter is disabled the receiver will receive signals. This can be from another FMTR151R transceiver or any other FM modulated signal that matches the carrier signal.

For reception a suitable antenna must be connected to the antenna terminal block. Transmitter output and receiver input uses the same antenna terminal. We recommend the Elsema ANT151, 151MHz antenna.

For technical specifications on the receiver refer to the R15105 receiver.

Operating Distance
Up to 5000m, depending on installation and type of antenna used. Recommended Antenna is Elsema ANT151.

(Range tests were done in an open area test site with line-of-sight operation and no interference. The receiver antenna wire was fixed vertically, away from any metal objects.)

Signal Strength Indicator

The 151MHz receivers have five blue LED’s on the board. The table below indicates the level of the valid transmitted signal.

                                                                                                                                               
Noise Strength Indicator
If more than 1 led is “ON” without a valid transmission, this indicates that there is noise on the frequency selected. Change the 3-way dipswitch on the receiver module to select a different frequency. The default setting is for 151.6MHz (All 3 dipswitches “ON”). Below is a table with the Dipswitch settings and the frequencies.

R15105	T15105

Technical Data

Block Diagram