Op er at ing in struc tions. 17, Use and func tion of con trols. 17, Ini tial ad just ments. 17 – Bird Technologies 8890-400 Series Manuale d'uso

Pagina 27: Operating instructions, Use and function of controls, Initial adjustments, Zero adjust

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Chapter 4

Operating Instructions

Use and

Function of

Controls

There are no operating controls for the Series 8890-400

Wattmeters. The Model BA-310 Blower Assembly, supplied

with some models, has a manual/automatic switch.

Initial

Adjustments

Before connection of the load, perform the following steps:

1. Wipe all conductors and insulator surfaces on

the transmission line face with a clean soft

cloth and check the RF input connector. Use a

self-drying, non-residue forming, contact

cleaner on the inaccessible portions of the con-

nector.

2. Check the 50 ohm input resistance of the load.

Refer to Section 1, Maintenance.

3. Zero adjust the meter. The meter should be

checked for zero set under no power conditions.

With no power applied, the meter pointer

should set exactly on zero. If adjustment is re-

quired, turn the adjustment screw until the

pointer is set at zero. Refer to figure 8.

17

Zero Adjust

Figure 8

Zero Adjust

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