q-Tech Q71B User manual

Q71B – 1200 bps FSK Radio Modem
for XL4 and DATRAN II eXcel RTUs
Quick Start Guide

Q71B – Quick Start Guide – v1.0 – February 2013
www.qtech.co.nz Tel: [phone]
Overview
The Q71B modem allows you to connect a DATRAN RTU via an RS232 serial port to a
DATRAN 1200bps radio communications system using the V.23 FSK protocol but without
the backward channel. This allows 1200bps in both directions as the modem is uses a
special turn around feature.
The Q71B interfaces to either a Tait TM81xx radio (fitted with a Q82 interface), or a
DATRAN Q80 telemetry radio.
The radio type needs to be specified so QTech can supply the correct cable.
Each Q71B is supplied complete with a 1m Radio cable and a 400mm RS232 serial cable.
The Q71B can also simplify radio network upgrades from 300bps to 1200bps as it
removes the need to change the internal modem hardware.
Prerequisites
The DATRAN II eXcel must have Q03 firmware v5.21 or later.
The Q90 software required is v3.27 or later.
If using the DATRAN XL4 RTU, all versions are compatible.
All versions of Workbench software are compatible.

Q71B – Quick Start Guide – v1.0 – February 2013
www.qtech.co.nz Tel: [phone]
Power Supply Connections
The Q71B is designed to operate from a supply voltage in the range 8.0V DC to 15.0V DC.
A supply voltage greater than 15.0V will blow the 500mA fuse inside the Q71B.
A supply voltage less than 8.0V will result in degraded or unreliable performance.
The DATRAN XL4 RTU and the eXcel (Rev D) RTU have two RS232 ports; both can use
the Q71B for analogue radio communications.
The significant difference between the two ports, is that the lower RS232 port (RS232-B)
on the Q22D has a +Vsup DC output supply line. The Q71B can be powered via this line,
so long as jumper J23 on the Q22D is in the 1-2 position. RS232-A port on the processor
does not have this supply line, so the Q71B must be powered through the three terminal
power supply connector, the power supply connections are shown on the top cover
Left Pin
Middle Pin
Right Pin
G
Power Supply Negative
+Power Supply Positive (8V – 15VDC)
Not connected
The default installation position of the Q71B is on the lower RS232 port.
All new RTUs will be configured with the correct jumper setting for this.
However, please check this jumper on existing RTUs before using a Q71B.
If using the modem on the RS232-A port do not apply power from both the
port and the external supply
If the DATRAN RTU is powered from a 24V DC system:
Do not connect the Q71Modem to this 24V DC supply.
Do not connect the Q71 modem to the RS232A port; use the 12V DC supply
that the radio uses & connect to the Q71 power connector.

Q71B – Quick Start Guide – v1.0 – February 2013
www.qtech.co.nz Tel: [phone]
Configuration
The DATRAN II eXcel must be configured so that it will use the Q71B for communications.
Power up the RTU and connect Q90 software to the RTU.
Navigate to the “Communications” tab and set “Device Type” as shown below.
The upper RS232 port is configured in the same way.
Q03 RTU Configuration XL4 RTU Configuration
Diagnostics
The Q71B has three status LEDs.
PWR – Power. Green LED is on when power is applied.
RX – Receive. Orange LED in on when radio mute is active.
TX – Transmit. Orange LED is on when RTU is transmitting.
If the Green PWR LED is not on check the fuse.
Tuning
Q03 RTU Tuning
Once the Q03D has been configured to use the Q71B, the transmit audio signal level can
be adjusted by pressing the “Set TX Level” button in Q90. This will make the Q71B
transmit a continuous tone, and an AC voltage meter can be placed across the pins of the
connector labelled “LVL” in the Q71B.
Turn the potentiometer anti-clockwise to reduce the signal level
Turn the potentiometer clockwise to increase the signal level
Note – this process will have already been performed as part of the factory setup at QTech
prior to delivery. The default level is -3 dBm (548mV) into a 600 Ωresistive load.
XL4 RTU Tuning
This is performed in a very similar method to the above Q03 process but via Workbench.