Summary of Contents for Ritron DTXM II Series
- Page 1 Rev. 07/14 RITRON DTXM SERIES II DTXM-X60 FAMILY PROGRAMMABLE WIRELESS FM MODEM TRANSCEIVERS VHF/220 MHz/340-400 MHz/UHF 6.25 kHz/12.5 kHz/25 kHz Channels Multiple Protocol...
-
Page 2: Model Identification
INTRODUCTION GENERAL The DTX Plus Series II modem is a wireless modem designed to operate on the frequency bands at VHF, UHF, and 220 MHz. It supports over-the-air data rates of 4800 bps in a 5.0/6.25/7.5 kHz channel, 9600 bps in a 12.5/15 kHz channel, and 19.2 kbps in a 25/30 kHz channel. -
Page 3: Fcc Regulations
8.3 in. (21.0 cm) Antennas other than the Ritron RAM-1545 must be tested with the DTXM for RF exposure compliance in the environment in which it is to be used per the FCC’s OET Bulletin 65, Edition 97-01 or Industry Canada RSS-... -
Page 4: Specifications
12.5 kHz channel 9600 bps 25 kHz channel 19,200 bps Modulation Voice Direct FM Data 4FSK Over-the-Air Protocols Ritron Proprietary Number of Channels Operating Bandwidth 38 MHz 220 MHz 28 MHz 340-400 MHz 20 MHz 400-430 MHz 30 MHz 20 MHz Synthesizer Step Size 2.5 kHz... - Page 5 FM Hum and Noise 6.25 kHz channel 35 dB min. 12.5 kHz channel 40 dB min. 25 kHz channel 45 dB min. Current Drain 1 watt 1.1 A max. 2 watts 1.6 A max. 6 watts 2.2 A max. 10 watts 2.6 A max.
- Page 6 DTXM I/O CONNECTOR AND INDICATORS 15-PIN I/O CONNECTOR Connector Pinout Name Description Comments AUDIO_IN Input Input for Audio to be transmitted in Voice mode AUDIO_OUT Output Line level receiver audio output SPEAKER Output Receiver audio output to drive a speaker Input Channel 1/2 or High/Low power Not Used...
- Page 7 This is the positive power supply input for the modem. Pin 7 Receiver Alginment This pin is the output pin of the modem IC’s input operational amplifier. It is used during alignment to set the receiver gain and DC offset for proper modem IC receiver decoding. This pin must be left unconnected by the user! Pin 8 RD (Receive Data)
- Page 8 INDICATORS The DTXM Modem has two indicators on the side of the unit, one green RX LED and one red TX LED. They function as follows: GREEN RX LED-This LED can be programmed to be illuminated under a variety of conditions. The choices are: Never (Off), whenever power is applied (Power On), when receiving, whether or not an actual signal is on the frequency (RX Synthesizer Lock), and when receiving and an actual data packet is being received (RX Data).
-
Page 9: Operation
OPERATION CHANNEL SELECTION Via the 15-pin connector, the DTXM supports one channel if the A/B pin (pin 4) is programmed for high/low power and two channels if the A/B pin is programmed as a channel select input. Channel A is set when the A/B pin is activated and the A/B pin is in the logic high state i.e. - Page 10 Warning: Although the output power can be set as low as 1 watt, and the module is certified as low as 1 watt, operation below 2.5 watts output power is not recommended. At low power levels, the output power can vary by 50% or more with variations in ambient temperature. Transmit Mode –...
- Page 11 Also, a fan option is available from Ritron which can significantly increase the duty cycle, up to 100% at room temperature in some cases. Contact Ritron for additional information on these options and special instructions on attaching heat sinks...
-
Page 12: Installation
“Setup.exe” on the CD Rom. The Ritron modem should be connected to the host computer by the 9-pin connector. The red wire in the cable should be connected to positive supply voltage for the modem while the black should be connected to the negative side. - Page 13 The button at the upper right is the Programmer Configuration button and is used to set the serial communications baud rate for communications between the programmer and the host computer. It defaults to 38400 baud, but can be set to other common serial rates. In addition, if the host computer baud rate is unknown, the Test Configuration button can be selected to auto-detect the baud rate.
- Page 14 particular model use. In addition, there are five other tabs and five buttons that can be selected. These are summarized below: PAGE TABS The page tabs show up on all of the pages. Clicking on a tab moves one to that page. Frequency-as explained above, this page allows the observing and entering of operating frequencies.
- Page 15 GENERAL TAB PAGE The General Page is shown below: The selections are: A/B Input One or Two Channel-Determines the function of the A/B pin. This pin can be used to control the power selection, high or low, for one channel, channel A or it can be used to choose between channel A and channel B, in which case, the output power is high for both.
- Page 16 Low Latency Protocol with no CRC-This is as close to a bit in/bit out protocol which can be supported by the Ritron radio modem. A synchronization pattern is affixed to the beginning of the transmitted stream, but after that, each symbol transmitted directly corresponds to two input bits.
- Page 17 Test Patterns (via Test Pin)-Selecting any of the selections in this box will cause a test pattern to be transmitted when the Test Pin (PTT) is active. If no selection is made, activating the Test Pin will cause the radio to transmit in analog/voice mode. The choices are: Bit Error Rate (BER)-A pn pattern is generated which allows for the computation of bit error rate, setting deviation, or observing an eye pattern.
- Page 18 ANALOG TAB PAGE The analog page allows selection of the analog/voice mode parameters and is shown below: The selections are: TX pre-emphasis-Selects whether the external audio signal is pre-emphasized i.e. had its high-frequency audio content boosted or whether the signal is sent with a flat audio response. Voice signals typically use pre-emphasis.
- Page 19 Carrier Detect On (dBm)-Sets the RF signal level in dBm such that the carrier detect pin will go active and the output audio, if squelch is selected, will go unmute. Carrier Detect Off (dBm)-Sets the RF signal level in dBm such that the carrier detect pin will go inactive and the output audio, if squelch is selected, will be muted.
- Page 20 RESTORE EE PAGE This page allows the configuration of the radio to be saved for loading into other DTX Series II radio modems. This page is shown below: If it is desired to save the current configuration, one of the three boxes should be checked. Besides not saving a configuration by not checking any option, there are three options: Saving all parameters, saving all except the squelch and RF power level (useful is the a radio modem already has power and squelch settings with are to be retained), and an option to convert older DTXM-X54 series products to the configuration of...
Need help?
Do you have a question about the DTXM II Series and is the answer not in the manual?
Questions and answers