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SMS 8301A-K Key to Serial Component Digital Converter
Frequency Response Adjustment
This adjustment sets the analog video frequency response from
the module input to the A/D converter input. Follow the steps
listed below:
1.
Connect 100% level line sweep to module video inputs.
2.
Observe response with oscilloscope at TP7 and adjust Y/G
Response C240 to obtain flat response to 5.5MHz.
NOTE:
If a source of line sweep flat to 6MHz is available, response
adjustments should be made to provide flat response to this frequency.
Key Video In H Phase Adjustment
This adjustment sets the timing of the modules EAV/SAV digital
timing reference output and digital H blanking. Follow the steps
listed below:
1.
Connect video input signal with sync to module key input.
2.
Remove shorting jumper on JP103 and short all three pins
together using a small piece of wire. Refer to
for
jumper location.
3.
Force the digital clamp to operate at mid-scale by shorting all
six pins of JP200 together with a short length of wire. Refer to
Figure 12 for jumper location.
4.
Change input format switch to position 3 to enable a test
mode which inhibits digital blanking.
5.
Observe digital output with digital signal analyzer. Adjust
R929 to place analog sync leading edge 50% point at Y sample
736 for 525 line standard, or 732 for 625 line standard.
6.
Remove wires used to short JP103 and JP200.