Atu Output Power; Connecting Dummy Load To Atu - Furuno FS-1575 Service Manual

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5.3 ATU Output Power

For the procedure for making adjustment of TX output power, refer to information in

"5.2 T/R Unit Output Power Adjustment and Measurement" on page 5-14.

As shown in Fig. 5.3.1 below, connect dummy load to ATU.

Connect a 50 ohm Dummy load for the HF band and a 10ohm + 250 pF antenna for the

MF band using a non-inductive resistor, respectively.

Furthermore, activate the automatic tuning function by selecting [MENU] -> 9.

SERVICE -> 3.RT SETUP -> 1.SETUP -> TX TUNE -> "ON."

Select Dummy load with appropriate power capacity according to transmission

1) Dummy resistors should have power capacity twice or more as much as TX

output power to be measured.

2) Capacitors should withstand a voltage of 10 kV or more.

3) Make the ground of the dummy load for the HF band as short as possible using

a copper band of 50 mm or more in width.

4) Particularly for the dummy load for the MF band, minimize impedance

between the antenna connection point and the ground connection point.

Fig. 5.3.1 Output Power Measurement circuit-1

CONFIDENTIAL (internal use only)

This confidential document is used only by FURUNO authorized persons.

It is strictly prohibited to reproduce the document in whole or in part without prior written permission of FURUNO.

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5.3 ATU Output Power

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