A: 1 Vcc
59mm
A: 2 Gnd
3.1mm
A
B: 1 RF Gnd
B: 2 RF in
1
B: 3 RF Gnd
C: 1 TXE (MOD TX_ON)
C: 2 TXD (MOD NC)
C: 3 AF in (MOD NC)
C: 4 RSSI
8.9 mm
Squelch adj
.
C: 5 SQF (MOD NC)
C: 6 AF out
Input gain
.
C: 7 RXD (MOD NC)
C: 8 +4.4V out
C: 9 0V
C: 10 PGM
1
C: 11 P1 (MOD TXD)
C: 12 P2 (MOD RXD)
C: 13 P3 (MOD NC)
C
Unit height
10mm
B
53.3mm
Figure 3: TR2M Footprint (Top)
Pin Description - TR2M
Pins Name
Function
4.5V-16V
Ground
A1
A2
Vcc
GND
B1
B2
B3
RF GND
RF
RF GND
RF ground
To the antenna
RF ground
C1
C2
C3
TXE (MOD TX_ON)
TXD (MOD NC)
Transmitter Enable. Low = ON, Open = RX mode. Internal 10kΩ pull-up to 4V
DC coupled digital data input for 3-12V CMOS logic. Leave open if unused
AC coupled Analogue Input Limit to 1Vpk-pk 10% to keep distortion <1.5% and
peak deviation >2.5kHz
AF in (MOD NC)
C4
RSSI
SQF (MOD NC)
AF out
DC level between 0.5V and 2.5V. 60dB dynamic range
Noise operated carrier detect. Open collector. ON/low = no signal
200mVpk-pk audio. DC coupled, approx 1V bias. Muted by squelch
Open collector output of data slicer suitable for Biphase codes
Regulated DC supply. 75mA max. drain. Present if unit is powered
Ground
C5
C6
C7
RXD (MOD NC)
+4.4V out
0V
C8
C9
C10
C11
C12
C13
PGM
Serial programming/configuration input at RS232 level
P1 (MOD TXD)
P2 (MOD RXD)
P3 (MOD NC)
Parallel frequency select inputs. Inverted logic, internal 10kΩ pullups to 4V
Notes:
1. TR2M receiver section inverts the sense of the baseband stream, so a logical inversion is present
between input of TX and output of RX. A version is available (TR2I) which inverts the transmit
datastream as well (resulting in no net inversions between a pair of TR2I radios).
2. Carrier detect on TR2M mutes the AF Out and RXD outputs. It can be factory disabled.
3. All the open collector outputs must be connected to Vcc/+4.4V out via a pull-up resistor.
4. The software incorporates a 1200baud dumb modem, compatible with that implemented in
TX2M, RX2M radios (I1200 tones and format)
5. With 1200baud modem mode enabled, parallel selection of channel is unavailable as the P1-P3
lines are used for modem input/output operations.
6. PGM and MOD TXD (pin 10 and 11) tolerate true ±RS232 levels. No buffering is required.
Radiometrix Ltd
TR2M Data Sheet
page 3
RADIOMETRIX [ RADIOMETRIX LTD ]
