RITRON, INC.
TABLE OF CONTENTS 1 2 INTRODUCTION 1.1 GENERAL 1.2 MODEL IDENTIFICATION 1.3 FCC REGULATIONS MODELS DTX-154 AND DTX-454 SPECIFICATIONS 2.1 GENERAL 2.2 TRANSMITTER 2.3 RECEIVER 3 DTX-154/454 INPUT/OUTPUT CONNECTOR 4 ACCESSORIES 5 OPERATION 5.1 CHANNEL SELECTION 5.2 POWER SUPPLY VOLTAGE 5.3 DUTY CYCLE/KEY-DOWN LIMITATIONS 5.4 OPERATING MODES 5.
1 INTRODUCTION 1.1 GENERAL The RITRON DTX Plus modules are programmable 2-way radios, which operate either in the VHF or UHF professional FM communications bands as well as a number of other bands in the 220 MHz and 350 MHz region. Each of eight channels can be programmed to contain a unique set of operating frequencies. The DTX Plus module is made up of two PC boards, an RF board and a control/loader board.
E designates the maximum power level: 3=3 watts 6=6 watts 9=10 watts F designates whether the control/loader board has a regulator and if so, at what current level: D=no regulator; the unit must operate from external, regulated +7.5 VDC and is limited to either 3 or 6 watts max. L=low current regulator; the power module is not regulated. Used for 10 watt version only. I=high current regulator; the unit operates from 10-15 volts at either 3 or 6 watts max.
This 2-way radio uses electromagnetic energy in the radio frequency (RF) spectrum to provide communications between two or more users over a distance. It uses radio frequency (RF) energy or radio waves to send and receive calls. RF energy is one form of electromagnetic energy. Other forms include, but are not limited to, electric power, sunlight and x-rays. RF energy, however, should not be confused with these other forms of electromagnetic energy, which when used improperly can cause biological damage.
• User awareness instructions should accompany device when transferred to other users. • Do not use this device if the operational requirements described herein are not met. Instructions: • Transmit no more than the rated duty factor of 50% of the time. To transmit (talk or send data), assert the PTT input pin. To receive calls, un-assert the PTT input.
2 SPECIFICATIONS 2.
RF Input/Output Connector BNC standard Power/Data Interface 15 pin subminiature D type Operating Temperature -30 to +60 C Maximum Dimensions (L x W x H) 3.6” x 2.3” x 1.0” including connectors Weight 6 oz. * Not Available Yet 2.2 TRANSMITTER Operating Bandwidth Up to the span of the sub-band RF Output Power (internally adjustable) 3 watt version (DTX-460-0 only) 6 watt version 10 watt version (DTX-460-0 only) 1 to 3 watts 1 to 6 watts (2.5 watts min.
2.3 RECEIVER Operating Bandwidth Up to span of the sub-band Sensitivity (12 dB SINAD @ 1 kHz w de-emphasis) 0.25 uV (-119.0 dBm) RF Input Impedance 50 ohms nominal Adjacent Channel Selectivity +/-6.25 kHz w very narrow IF +/- 12.5 kHz w narrow IF 45 dB min. 60 dB min. Spurious and Image Rejection IF/2 Image & other 60 dB min. 70 dB min. Intermodulation Rejection 68 dB min. FM Hum and Noise Very narrow channel (5/6.25/7.5 kHz) operation Narrow channel (12.5/15 kHz) operation 40 dB min.
3 DTX INPUT/OUTPUT CONNECTOR Connector Pinout Pin Number Name Description Comments 1 CS0 Channel Select low bit 2 CS1 Channel Select mid bit 3 CS2 Channel Select high bit 4 MIC IN Microphone Input 5 CSN High/Low Power or Channel 1/2 6 RAW SUPPLY Power Supply Input Positive Supply voltage input. 7 AUX IN Auxiliary Input Wideband input for data. 8 AUX OUT Auxiliary Output Wideband output for data. 9 PGN IN/OUT Programming I/O External programmer connects here. 10.
reference for all inputs. Pinout Description Pin Number Description 1 CS0-Least significant bit of the channel select lines. Active high 5 volt TTL/CMOS level. Internal 10 k pull-up to +5 volts. 2 CS1-Mid bit of the channel select lines. Active high 5 volt TTL/CMOS level. Internal 10 k pull-up to +5 volts. 3 CS2-Most significant bit of the channel select lines. Active high 5 volt TTL/CMOS level. Internal 10 k pull-up to +5 volts.
ohms. Therefore, it is not recommended that this output drive loads with less than 1000 ohms unless the resultant voltage drop is accounted for. 9 PGN IN/OUT-Connect via RITRON DTXP-PCPK PC Programming Kit to computer for programming the unit. 10 CTS-Clear-To-Send output from the unit which indicates that the unit is transmitting a carrier at the correct frequency and power level and is ready to accept an input signal to be transmitted.
4 ACCESSORIES Note: Programming kits are for use by authorized service/maintenance personnel only. The Programming Kit for DTX-154/454 radios (via compatible computer) is model DTXP-PCKT. It includes: 1) Programming software diskettes, 3.5” (qty 2). 2) 1 25 pin PC to 6 pin modular adapter cable with built-in interface circuitry. 3) 1 modular adapter to DB-15 connector cable with power cable. Factory programming of channels and features is also optional. Contact the factory for details.
5 OPERATION 5.1 CHANNEL SELECTION The DTX module supports eight channels. The desired channel is chosen via pins 1, 2, and 3 of the 15 pin connector as shown: Channel Pin 3 (CS2) Pin 2 (CS1) Pin 1(CS0) 1 2 3 4 5 6 7 8 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 = Logic low (0 to 0.3 VDC) 1 = Logic high (3.5 to 5.0 VDC or left unconnected) A logic low is a voltage level below 1 volt while a logic high is a voltage level above 3.5 volts.
5.3 CURRENT DRAIN VS SUPPLY VOLTAGE The current drain of the module is a function of the supply voltage, the RF output in transmit and the regulator option. The internal 7.5-volt regulator is a switching type such that the current drain actually decreases with an increase in supply voltage. Typical current drain values are shown in the table below: Receive Mode Supply Voltage 7.5 V 11.0 V 12.5 V 16.
13.5 V 5.4 RF PA is unregulated 2.5 A DUTY CYCLE/KEY-DOWN LIMITATIONS The major heat generating component within the modules is the RF power amplifier which has a maximum temperature limit that should not be exceeded. In addition, the temperature within the module itself must be kept below the maximum temperature of the reference oscillator to ensure that regulatory frequency stability limits are observed.
5.5 OPERATING MODES 5.5.1 RECEIVE Carrier Detect and Squelch Operation The DTX is a transceiver; i.e. it can receive and transmit, although not at the same time. A carrier detect system exists within the unit to detect the presence of a carrier which controls the logic state of the DCD (data carrier detect) output. The RF levels at which this output changes state are programmable.
High/Low Power If RNet compatibility mode is not programmed into the unit, high and low power levels can be programmed into the unit on a channel by channel basis. High power is selected by placing the CSN input at a logic high state. Placing the CSN input at a logic low state chooses low power. The CSN input has an internal pull-up resistor; it will assume the high state and the module will be set for high power when left unconnected.
