Coup: 05P0875 (Fs-2575 And Fs-5075) - Furuno FS-1575 Service Manual

5.7.6 COUP: 05P0875 (FS-2575 and FS-5075)

Variable resistors on the COUP boards of the ATU are used to make adjustment of
"IA" ; antenna current.
Connect a 10 ohm + 250 pF dummy load to the ATU, and then make adjustment of the
"R21" IA ADJ. variable resistor so that an Antenna current flowing through the dummy
load in the 2 MHz will come to the IA reading.
Fig. 5.7.26 Location of ATU IA ADJ. Variable Resistors
10.0A
9.0
FS-5075
8.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
1.0 2.0 3.0
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It is strictly prohibited to reproduce the document in whole or in part without prior written permission of FURUNO.
3900.0kHz
2182.0kHz
1605.0kHz
4.0 5.0 6.0 7.0 8.0 9.0
IA
5-54
R21: IA Adjustment
R20: IA Adjustment
Fig. 5.7.27 Example of
IA Reading Characteristics
10.0A
5.7 Board Adjustment
AT-5075
AT-1575