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Radio system testing with the antenna connected, Vswr, Figure 6-2: transmitter vswr testing – Codan Radio MT-4E Analog and P25 Digital - Maintenance Guide User Manual

Page 67: Made in canada

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MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS | MAINTENANCE GUIDE

Chapter 6: Additional Radio System Tests Page 59

RADIO SYSTEM TESTING WITH THE ANTENNA
CONNECTED

VSWR

An antenna system VSWR test can be performed by connecting a Wattmeter such as the Bird Model 43
Wattmeter between the antenna port of the fi ltering equipment and the antenna as shown in Figure 6-2.
Measure the forward power and the refl ected power using the Wattmeter and calculate the VSWR. The
Wattmeter can also be placed between the transmitter and power amplifi er or between the transmitter
or power amplifi er and duplexer to measure the VSWR at these locations.

Figure 6-2: Transmitter VSWR Testing

TRANSMITTER

CNTL
BUS

MIC

RF OUT

A D

ANALOG
DIGITAL

NORM
OFF
KEY TX

MIC MODE

REF

IN

USB

FREQUENCY (MHz)

MADE IN CANADA

MODEL # CODE

RECEIVER

NORM

SQ. DISABLE

OFF

CNTL
BUS

A D

RF N

I

REF
IN

USB

FREQUENCY (MHz)

MADE IN CANADA

MODEL # CODE

VOL

SYSTEM REGULATOR

METER

+

-

MADE IN CANADA

ON
OFF

SPKR

INT

EXT

EXT

SPKR

OFF

POWER

ON

2

1

5

4

3

6

7

8

11

10

9

FUNCTION

12

REPEATER

CONTROL

RX B

TX B

RX A

TX A

PULL DOWN
TO REMOVE

9

5

3

7

11

15

9

13

3

7

11

15

SWITCH A

SWITCH B

Directional Wattmeter

To Antenna

RF OUT from Tx

to Duplexer

Antenna port on Duplexer

to Wattmeter