So, long story short, my friend has a framemeister, hes got a SNES Jr., I preformed the Voultar RGB amp board mod. (The new board which doesnt require manually bridging a solder point for anything or doing a seperate single wire mod for rerouting Csync as that used to be needed with his old boards) I hooked it up via scart cable to my BVM in the following way:
SNES Scart cable>Female Scart socket cable that terminates in RGBS BNC (dont know if my female scart socket cable has sync stripper) and it plays perfectly.
My SNES SCART cable is a very cheap older unbranded chinese job.
I take it over to my friends place, we hook it up directly to his Framemeister's RGB in port (with Female SCART socket to Mini DIN adapter of course) via HIS Retro Gaming Cables SNES SCART cable (wired for Csync). This initially produces NO picture. We do have sound. After going into the sync options and dialing the sync level to around 5 or 6, we get EXTREMELY intermittent picture. Visible for half a second then gone for a few seconds etc.
Im thinking its just a bad cable. Its been in his setup for a while, he used to use it with an old model 1 SNES and it seemed to work fine. Physically, part of the SNES side connector has started to deteriorate and break (as all of my RGC cables eventually did) but I dont see any wires showing through or anything. We hooked his old SNES up again this way and initially got no picture at all but after trying about 5 times of re seating the game we got it to display fine with no drops, so maybe was the console or dirty game?
We also hooked the same cable up to his NS1 N64 thats also had Voultars RGB mod and we get no picture at all. (again this N64 displayed fine on my BVM setup with cheapo Chinese cable)
My thoughts are, he either needs some sort of sync stripper? OR The cable is trash? Or maybe theres something the Framemeister isnt liking here, sync wise?
We are at a total loss, any help is appreciated!
Framemeister Expert help needed! (SNES Jr RGB mod sync issue
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Capitalistix
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NewSchoolBoxer
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Re: Framemeister Expert help needed! (SNES Jr RGB mod sync i
I don't have a Framemeister but I know it's a bad idea to use TTL sync with it. In other words, csync at 2.5-5V level is bad and ~300mV level aka 75 ohm level is good. All consoles with native csync output TTL level. Could put resistor in console mod or cable, cable is more common and usually makes more sense. Resistor in both places will kill video.
I'm confused how you could use cheap Chinese Scart cable on a BVM. It's like you're going for consumer CRT quality. I'm confused why you mention a sync stripper. If you're PAL then I get it but no NTSC cable would use a sync stripper chip on luma or composite video. The cable would also cost $10 more due to the chip's cost. You should specify PAL or NTSC console. I know RGB sits outside of PAL vs NTSC but PAL has +12V whereas NTSC has csync on the same pin.
You haven't proven you did the RGB mod correctly. Verify the solder joints and resistor and capacitor placements. You have a multimeter if you're doing mods right? Do you know the continuity test? It's the diode icon. Sends a small DC voltage and meter beeps if the connect is good between two points. A capacitor in the path will either block the beep or only allow a beep for a second. Use the meter in this way.
Can you unscrew the cable? Look for resistor on the sync pin. If there and 330-470 ohms or some other high value then it's 75 ohm sync, which is fine. If you see a chip on a PCB then it's a sync stripper cable. Look for the resistor on the PCB. If not there then getting TTL so you need to add one. All sync chips output TTL by default. TTL is normal sync for rest of world but in our scene we invented 75 ohm csync.
If no PCB or resistor but you see 220uF capacitor then do capacitor measure test from that pin to the csync, luma and composite video multiout pins and figure out which one it is. As in, which one shows a ~220uF value. Is kind of a pain to get multimeter probe on one multiout pin but can be done. If no capacitor then do continuity test on those pins. If csync pin beeps then do resistor measurement test to confirm correct value.
At this point, you should know which kind of sync you have. Only bad option here is csync with no resistor.
Other greater concept is electrical isolation. Change only 1 thing and test. Use another, better Scart cable. Use a different SNES power supply. The original one can die or be near end of life. Use a different SNES. Use a different television. Use Composite or S-Video with Framemeister. Use Composite or S-Video without Framemeister. Rule out which thing isn't working as best you can. You've done a pretty good job of this by verifying cable doesn't work on one N64 + Framemeister -> BVM but does work on N64 -> BVM and SNES -> BVM. Not proof since mods can be done wrong. No one will guarantee their product works on a modded console.
Could be more than one thing wrong. You 100% do not need a sync stripper (if PAL) for csync, unless cable is low quality, which it is. BVM and PVM with very few exceptions, will accept every from of sync in existence and csync over TTL or 75 ohm voltage level. Framemeister will safely accept composite video as sync, luma as sync or 75 ohm level csync. Again, do not feed it TTL.
I'm confused how you could use cheap Chinese Scart cable on a BVM. It's like you're going for consumer CRT quality. I'm confused why you mention a sync stripper. If you're PAL then I get it but no NTSC cable would use a sync stripper chip on luma or composite video. The cable would also cost $10 more due to the chip's cost. You should specify PAL or NTSC console. I know RGB sits outside of PAL vs NTSC but PAL has +12V whereas NTSC has csync on the same pin.
You haven't proven you did the RGB mod correctly. Verify the solder joints and resistor and capacitor placements. You have a multimeter if you're doing mods right? Do you know the continuity test? It's the diode icon. Sends a small DC voltage and meter beeps if the connect is good between two points. A capacitor in the path will either block the beep or only allow a beep for a second. Use the meter in this way.
Can you unscrew the cable? Look for resistor on the sync pin. If there and 330-470 ohms or some other high value then it's 75 ohm sync, which is fine. If you see a chip on a PCB then it's a sync stripper cable. Look for the resistor on the PCB. If not there then getting TTL so you need to add one. All sync chips output TTL by default. TTL is normal sync for rest of world but in our scene we invented 75 ohm csync.
If no PCB or resistor but you see 220uF capacitor then do capacitor measure test from that pin to the csync, luma and composite video multiout pins and figure out which one it is. As in, which one shows a ~220uF value. Is kind of a pain to get multimeter probe on one multiout pin but can be done. If no capacitor then do continuity test on those pins. If csync pin beeps then do resistor measurement test to confirm correct value.
At this point, you should know which kind of sync you have. Only bad option here is csync with no resistor.
Other greater concept is electrical isolation. Change only 1 thing and test. Use another, better Scart cable. Use a different SNES power supply. The original one can die or be near end of life. Use a different SNES. Use a different television. Use Composite or S-Video with Framemeister. Use Composite or S-Video without Framemeister. Rule out which thing isn't working as best you can. You've done a pretty good job of this by verifying cable doesn't work on one N64 + Framemeister -> BVM but does work on N64 -> BVM and SNES -> BVM. Not proof since mods can be done wrong. No one will guarantee their product works on a modded console.
Could be more than one thing wrong. You 100% do not need a sync stripper (if PAL) for csync, unless cable is low quality, which it is. BVM and PVM with very few exceptions, will accept every from of sync in existence and csync over TTL or 75 ohm voltage level. Framemeister will safely accept composite video as sync, luma as sync or 75 ohm level csync. Again, do not feed it TTL.
Last edited by NewSchoolBoxer on Thu Jul 21, 2022 5:59 pm, edited 1 time in total.
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NewSchoolBoxer
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Re: Framemeister Expert help needed! (SNES Jr RGB mod sync i
You know what, I've read people saying Retro Gaming Cables are very good and people saying they were very good until X number of years ago. Sorry I can't help you on where good Scart cables come from.Physically, part of the SNES side connector has started to deteriorate and break (as all of my RGC cables eventually did)
Chipnetics and maxtherabbit who post here sell VGA multiouts for Nintendo and Sony consoles. I know maxtherabbit can make a PAL one and you can specify which sync you want and price is only $25 shipped to US. I use that + VGA to BNC cable to PVM or VGA to Plasma or DVI to capture card.