User's Manual

Sub D 15 Pin Connector

The DR-142/442 is equiped with a 15 pin female sub D connector with the following functions:

Pin# Function

1 least significant channel select bit (CS0)

2 channel select 1 (CS1)

3 Most significant channel select (CS2)

4 N/A

5 N/A

6 + 8 to 16.7 VDC input

7 N/A

8 auxilary ouput

9 PC programing port

10 Volume adjust with external 10k pot

11 Auxilary monitor input (pull to ground to open squelch) or valid tone indicator (low)

12 Speaker output

13 Carrier detect output (pulls to 5 VDC through 390 ohms)

14 N/A

15 ground

INTRODUCTION

GENERAL

RITRON's DR-142 receiver module is designed to operate over 136-156 MHz or 154-174 MHz. The DR-

442 operates over 400-420 MHz or 450-470 MHz. The units receives voice through a nominal 1 watt

speaker output. It supports up to 9600 bps 4-level FSK through its auxiliary output port.

Each radio can be “dealer or factory” programmed to contain a unique set of eight operating frequencies

and options. 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. Quiet Call (CTCSS) or

Digital Quiet call (DCS) tones can be programmed per channel.

Model Identification

The DR-142/442 model, serial number and FCC Identification are displayed on a label located on the

bottom of the PCB.

FCC Label

An FCC label must be visible on the unit as installed in its final configuration. If the unit is to be used as

shipped from RITRON, this would be no problem since an FCC label is affixed to the bottom of the PC

board. If the DR-142/442 is to be installed in an enclosure, the installer must ensure that either the FCC

label on the unit is visible through a door, window or other opening, or add a label to the outside of the

enclosure. If a label is to be added to the outside of the enclosure, the label must be of a type which is

not easily removed or damaged and contains wording: Contains FCC ID: AIERIT17-142R for the DR-142

and FCC ID: AIERIT17-442R for the DR-442.

Unauthorized Modifications

Note: The manufacturer is not responsible for any radio or TV interference caused by unauthorized

modifications to this equipment. Such modifications could void the user’s authority to operate the

equipment.

MAINTENANCE INFORMATION