Grass Valley 8901 - Manual (Page 17)

8901/8902/8906 Instruction Manual 17
Module Adjustments
Module Adjustments
The following adjustments can be made from front edge and on-board con-
trols on the module circuit board. There are no remote control adjustments.
Gain Adjustment
Overall gain of the outputs on these modules can be adjusted ± 2 dB with
the front edge GAIN potentiometer R1. To adjust gain:
1. Connect one of the output BNCs to a waveform monitor.
2. Adjust the input signal to the desired amplitude with the GAIN
potentiometer.
Equalization Adjustment
On the 8902 and 8906 modules, equalization can be fine tuned with the
front edge EQ potentiometer, R2.
To fine turn equalization:
1. Connect a test signal such as Multiburst (up to 20 MHz) to the module
input and terminate the unused loop-through input.
2. Use the front edge EQ potentiometer to adjust for equal frequency
response on the multiburst signal while monitoring an output from the
module.
White Clip Adjustment
The white clip level of the signal can be set with the White Clip Level
adjustment, R95. The adjustment range is from 500 mV to 1200 mV.
To adjust the white clip:
1. Set jumper JP3 to On (pins 2-3) and place the module on an extender if
possible.
2. Connect an output BNC to a waveform monitor.
3. Connect 100% Color Bars to the input. Use one of the following
methods to make the adjustment:
a. Unterminate the output you are monitoring and adjust the white
portion of the signal to be below 1 V.
b. Leave the output terminated and adjust the white portion to clip
where desired for your application.