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Old 01-13-2016, 03:11 PM
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Electronic M Electronic M is offline
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Join Date: Jan 2011
Location: Pewaukee/Delafield Wi
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If you have a test pattern generator with a strong variable level video output I'd use it the try injecting video to various points in the monochrome signal chain (use a cap in series with the video lead to prevent DC from damaging the unit unless you know the generator has one built in). Start at the monochrome video output (if injecting at the grid gives you video work towards the detector till you loose it otherwise work towards the CRT till you get video). If you have an audio/RF signal generator you may be able to use that in place of the video generator by finding a frequency that is a multiple of the vertical and or horizontal scan rate...I did that in a pinch once, and it worked well....So well that I ended up playing with different frequencies to see what kinds of patterns I could make.

If you have an oscilloscope you can trace the video forward from the detector till you loose it. Best to use a vertical bar gray-scale test pattern for the scope method since it will give you a nice easily recognizable stair stepped pattern between the sync pulses.
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