Use Manual

2
INTRODUCTION
General
RITRON's DTX-145M transceiver module operates on one of 5 frequencies in the license free VHF
band. Typical radio parameters such as frequency, power, deviation, deviation balance, squelch level and
audio input and output gain are PC adjustable and have been set up at the factory for typical operation.
The transceiver is a single board unit with components on one side and pin for pin compatible with the
DTX-145.
The unit supports voice through a microphone input and a nominal one watt speaker output or data through
the auxiliary in and auxiliary out ports. Each radio is preprogrammed with the following frequencies which are
compatible with the Ritron JBS-146M and RQX-156M:
DTX-145M
JBS-146M
Frequency
BW
Channel
Table number
MHz
wide or narrow
1
1
154.6
WB
2
2
154.57
WB
3
19
151.82
NB
4
20
151.88
NB
5
21
151.94
NB
6
22
154.6
NB
7
23
154.57
NB
8
23
154.57
NB
Pins 1, 2 and 3 of the DB-15 connector select the channel. When all three channel select inputs are tied to
ground the radio operates on channel 1. The channel selection is done in a binary manner on the CS2, CS1
and CS0 inputs. Separate RX and TX Quiet Call (CTCSS) or Digital Quiet call (DCS) tones can be programmed
per channel. The unit is factory set to transmit 2 watts when operating at 12.5 VDC. The standby current drain
at 12.5 VDC is typically about 22 mA.
Model Identification: DTX-145M-AB
The DTX-145M is available in an aluminum encased version with a BNC connector or a board-only.
The board only version can have one of a variety of RF connectors.
A is the connector type:
B = BNC
C = BNC on flying coaxial cable
M = SMB
S = SMA
X = MCX
B designates the case:
E = enclosure (DTX-145M-BE has BNC connector and right angle DB15)
R = board only with right angle DB15, no enclosure
V = board only with vertical DB15, no enclosure
Contact the RITRON sales department for further details.
A board only version with an SMB connector would be DTX-145M-MR or DTX-145M-MV.