Tait T800 SL2 25W, Service Manual

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M8SL2-00-002-812
T854 Functional Testing C4.5
© Copyright Tait Electronics Limited August 2004. All rights reserved.
4.5 Frequency Response
If the T854 has been correctly adjusted, the pre-emphasis and limiting responses should
closely match those shown in Figure 4.2 and Figure 4.3 respectively.
Note: The limits shown on these graphs should not be exceeded.
1. If you are using an RF test set, turn off all filters.
2. Measure the pre-emphasis response as follows:
Reduce the line level to give ±1kHz (±0.8kHz) [±0.5kHz] deviation at 1kHz.
Sweep the modulation frequency.
The response should closely match that shown in Figure 4.2.
3. Measure the limiting response as follows:
Set the line level to give ±3kHz (±2.4kHz) [±1.5kHz] deviation at 1kHz.
Increase the line level 20dB and sweep the modulation frequency.