Sync-ope : sync restoring circuit - next revision ideas

I’ve used the MisMatcher which has a similar circuit. It isn’t the same thing as a TBC but it has the same practical effect in terms of stabilizing a glitched signal for capture devices, projectors, etc.


Mismatcher is actually what I’ve been having trouble with… hmm, maybe there is something wrong with my build.

I’ve been glitching high definition component video using rotary potentiometers and am wondering if anyone has or will build something like this that restores sync for high definition video. I use a scaler that does an ok job of keeping my monitors from cutting out to a blue screen, but something like this for HD seems like what I might need. Is it possible to affordably build sync-ope for HD with YPbPr or Rgbhv inputs?

I’m working on a blanking/clipping circuit kind of similar to Sync-ope, using a digital sync/blanking generator, in order to choose SD/HD framerate, resolution and scan type with switches (might even implement a format auto-detection feature but still have to write and simulate the code).

Then Sync-ope can definitely be set for HD formats since the horizontal and vertical blanking timings are set using two monostables (74HC4538) and the timings are defined using trimmers/resistors/capacitors, following the formula T = 0.7RC. The values shown in the Sync-ope schematics covers NTSC/PAL, then since vertical sync is the same for SD and HD (50Hz/60Hz), the vertical blanking timings doesn’t need to be changed/can be achieved using the existing RC values. Then not sure for the horizontal blanking interval, may ask to lower the capacitor value to achieve a better precision when setting the timings with the trimmers, though might not be even needed. I’ll give it a go with my sync-ope and report.


Great to hear you’re working on that. What inputs will it have because sync-ope appears to just have composite and idk how to change that

It will only have a single RCA 75R input which can work with Composite/Component/RGB (and why not S-video with the right adapter). Cause Component and RGB only contains sync in Y and G signals respectively, so only this signal needs to be stabilized, Pb/Pr and R/B can be glitched without stabilizing them as long as the Y or G is in-spec. That was why I was saying that Sync-ope can be used for HD too, as you only need to stabilize the signal that contains sync.

Ok thank you so much for explaining that!

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i guess that in this use case the knob that mixes between clean and glitched signal on the sync_ope would only work for the channel that contains sync…

although a passive mix between the other channels should work fine since they are already in sync

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Thanks and thanks for all your work!

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