Thruline RF Power Meter, Model 4421
37
11. Press dBm.
Note:
“dBm” should change to “SWR”.
12. Press FWD.
Note:
“SWR” should change to “FWD” and “ ” to “.0000 W” (or a very low number).
13. Hold down MAX.
Note:
“.0000” should change to “1.0000”.
14. Release MAX.
Note:
“1.0000” should change to “.0000” (or a very low number).
15. Press LIGHT.
Note:
The back-light should turn on.
16. Press LIGHT.
Note:
The back-light should turn off.
17. Press s (up).
Note:
The power meter should change ranges each time it is pressed until it reaches “0.000 KW”.
18. Press
t
(down).
Note:
The power meter should change ranges each time it is pressed until it reaches “0.00 W”.
19. Turn the power meter OFF.
Power Meter Repair
Replacing Fuses
1. Gently pry the fuse drawer out of the AC module. The fuse holder does not detach from
the AC module. See
Figure
17
.
2. Install the replacement fuses then close and secure the fuse holder. Fuse 1 is a spare
fuse and fuse 2 is the active fuse.
WARNING
To avoid personal injury, disconnect the power cord from the AC line before
performing any maintenance, including fuse replacement or changing the line voltage
setting.
WARNING
To avoid personal injury, disconnect the power cord from the ac line before
performing any maintenance, including fuse replacement.
CAUTION
Failure to install the properly rated fuse may result in equipment damage or nuisance
failures.
