Having Trouble synching a video waveform generator with a visual cortex

Hi, i recently bought a second hand video waveform generator and I’m having a bit of trouble synching it with my visual cortex.
Ive hooked up the Waveform Generator to sync with the field sync on the Cortex ( the vertical sync) and this keep the low oscillation rate relatively synced, but docent seem to sync the high oscillation rates.

I suspect that the Waveform Generator is running slightly out of sync, there is still slight movement when synced with a low oscillation rate, and this movement is enough to completely un sync it at higher rates.

aka, im getting synced lines that slighty wiggle up and down when the Waveform Generator is running slowly, but it just turns into unsynced noise when its running faster.

Does anyone know any fixes for this problem? maybe theirs some setting I need to change on the back of the Waveform generator. Or might it just be that the second hand waveform generator is a lil busted, and if so is there anyway to fix it?

Thanks so much for the help!!

Is the module receiving sync from the Cortex over the 14 pin ribbon cable connection the CV/gate lines on the power bus (VWG does not use 14 pin sync, see below)? I’m not personally too familiar with the VWG but this is probably the best way to sync it. You can also use a patch cable to the sync input but in that case you’re only getting one sync at a time, but probably you want to keep horizontal sync when you’re trying to sync vertically and vice versa. Patching horizontal sync from the Cortex to the oscillator sync input will probably sort of work (at vertical oscillator frequencies) but will still scroll vertically unless you have the oscillator frequency tuned just so. Getting a sync cable from LZX or making a 14 pin ribbon cable is probably your best bet for using modules from the Visionary line (which I have no experience with, but I use a lot of Cadet modules that use the same sync connections)

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The VWG syncs to Cortex via the power bus. Visual Cortex sends those syncs on the power bus, when the “HV Sync to power bus” switches are turned ON, on the rear of the module. Originally the Visionary series Video Sync Generator was used with VWG and synced it via the power bus. Cadet 1 will do it too.


I’m having this same issue with my secondhand VWG I just got. Toggled HV sync to power bus on back of VC, VWG sync bus set to 1 (the other settings completely unsync it so I know Bus 1 is correct), and also have RCA sync going out VC to a Prismatic Ray. PR is 100% stable at the higher frequencies, but my VWG is jittery on all but the lowest 2 frequency ranges, sometimes even the 2nd lowest will be a bit jittery. Everything is powered off of a 4MS Row Power 45. Other modules sharing power are just Color Chords and Memory Palace w/ DC connector. Any tips?

Have you tried isolating just Cortex and VWG on the power bus to see if that improves your results?

Just did. Switched from my Row Power 45 to my Mantis power bus and removed everything else except Cortex, VWG looks crystal clear. However, even if I add a module (Make Noise Morphagene) with less power draw than most of my other modules on the negative rail (so VC and VWG on Section A of my Mantis and Morphagene and ABC mixer on Section B or C, both of which share negative rail only with A), a considerable amount of noise is added. I have now seen firsthand why sync over power in most situations is not ideal. :slight_smile: Good to know the module fully works at least. One interesting thing to note is that the sync switch needs to be flipped depending on the frequency setting I have. Higher freqs need sync bus 2 and lower freqs need sync bus 1. This has served as a great promo for the upcoming dual VWG for me, I think I’ll have to end up letting this module go since I don’t have a cleaner power solution.

Edit* actually briefly had a config that worked with no issues, it was largely my non-LZX modules causing noise trouble, but I’ll have to keep messing with how I can integrate Memory Palace in this setup. Seems to be a different issue.

Thanks for experimenting to the bottom of the issue. Each generation of LZX modules has improved in the battle against power supply noise and the upcoming modules will be the least noise prone to date. Given the improvements, it might be helpful to keep your VWG for 1V video-rate modulation and noisier textures. It could still prove to be a useful tool.