Channel Crosstalk Test; Table 5-5. Suggested 8520C Velocimeter Channel Crosstalk Combinations - Honeywell Chadwick-Helmuth 8500C Maintenance Manual

Chapter 5 - Maintenance And Repair
ad. Repeat steps r through ac for the Velocimeter channel and magnetic pickup channel
combinations listed in Table 5-4.
5.5.2.4

Channel Crosstalk Test

This test measures the amount of energy induced by a signal on another 8520C channel. This is done
by placing a signal level on one channel and then measuring the relative signal amplitude of the other
channels listed in Table 5-5.

Table 5-5. Suggested 8520C Velocimeter Channel Crosstalk Combinations

Velocimeter
Channel
(Cable 8278)
a. Connect cable 8278 to Velocimeter channel 1 and remove cable 10502 from magnetic
pickup channel. Set up signal generator as follows:
(1) For channel connected to magnetic pickup input, set to Frequency = 100.00 +/-
0.1 Hz, Waveform = Sine wave, Amplitude = 19.0 mV pk.
(2) Monitor signal generator output with spectrum analyzer with marker at 100 Hz.
Adjust signal generator output channel connected to Velocimeter input until
amplitude is 13.44 +/- 0.05 mV RMS.
b. Press SPECTRUM key on 8500C/C+.
c. Press SETUP key.
d. Key in 1000 <Hz> with numeric keys.
e. Select SEEK field with arrow keys.
f. Press CHANGE soft key to select <SEEK OFF>.
g. Select INPUT field with arrow keys.
5-20 Chadwick-Helmuth A Business Unit of Honeywell International, Inc.
1
2
3
4
5
6
7
8
9
10
11
Velocimeter
Channels
(selected one at a time in test
step)
2-12
3-12
4-12
5-12
6-12
7-12
8-12
9-12
10-12
11-12
12