Csync levels, PVMs, Frameister, etc.:

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FBX
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Csync levels, PVMs, Frameister, etc.:

Post by FBX »

I was just discussing with Drew over at Retro-Access about csync voltages and what various range maximums are. Now the SCART standard from what I'm told is to have a range of 220mVpp to 950mVpp. Service manuals for my PVM suggest it can handle a whopping 4Vpp for csync, yet it handles my recent experiment with 315mVpp on my SNES just fine. I heard from Drew that the Framemeister often has trouble with lower csync voltage, causing certain devices to only show up on it if you lower the 'Synce Level' all the way down to 1. I just checked the FM with my 315mVpp SNES csync, and it didn't have any problems with it.

So I guess I have a few questions for those in the know about this:

1. My PVM' service manual claiming 4Vpp. Does this mean I can have TTL or attenuated csync running into it and it will be fine either way? What would the lower limit be then since it handled 315mVpp no problem?

2. What are some devices that have issue with the FM in being too low on the csync voltage? I heard of someone having a problem with a Borti board where it would only work on Sync Level 1 in the Framemeister. Just curious about these nebulous issue with csync.

As many videos as there are that try to 'demystify' csync, it seems it remains still somewhat 'mystified'. :-P

-FBX
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maxtherabbit
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Re: Csync levels, PVMs, Frameister, etc.:

Post by maxtherabbit »

"True" TTL levels are 5vpp, however every console I've personally measured was in the neighborhood of 3.3, which is actually LVTTL
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