CADETS best way to test / debug

HI guys just finished building a bunch of modules. First time using video modules so I’m wondering what is the best way of testing. Should I attach the C1 to C4 and check if I see a raster in my scope? Do I need to input something or the C1 generates also sync without input?

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It depends on what modules you have build. You can power them up and see if they give image.
for example, if you have these: C1 sync generator, C2 RGB Encoder , C9 VCO

Basic setup test:
Connect the modules to power. connect the 14pin sync header from C1 to C9
Patch the VCO output to the Red input of the C3 Encoder
connect the RGB Encoder output to your TV (a CRT or something with a composite input)
You should see vertical or horizontal lines
Same goes for the C4 Ramps, you should see static horizontal or vertical gradients on the outputs.

note: the Sync generator generates sync on its own.

If you want to test the modules separately, or check for errors:

check for shorts at the power header, look at the IC’s, are the correctly inserted? check the polarity of the electrolythic caps. Check the solder joints, reflow if necessary.

power up C1 and measure (scope) the sync outputs of the frontpanel (H, V and Frame)
You should see pulses like these: (take note of the frequencies)


great today i’ll start that!!!