Ask general Genesis/MD/Sega CD/32X questions here (for new members)

[Teh Lurv]

Quick tech question:

I stopped at my local thrift store after work this evening to browse and I found someone donated a bunch of random European electronic stuff. Among the items was several SCART cables including a mini-DIN 9 to SCART cable. The store wanted $3 for it so I figured "Why not?" and bought it. What are the chances that this cable matches the pin-out for the Model 2 Genesis? I have nothing to plug the SCART end into and I was curious on the odds should I ever get around to buying a SCART to component transcoder.

[EyeDeeNo76]

@Goati I have been using white lithium grease on plastic components in electronics, silicon grease can be hard clean off to work on plastic components again. As for the microswitches in the ASCII fighter stick, no. I think it is the same as SG-6 https://youtu.be/l7-SizOiy0I?t=62

[EyeDeeNo76]

Why does Super Street Fighter II and Virtua Racing not have the rainbow banding like may other games on my stock HD non-TMSS model 1 VA3 Genesis? I using composite on a Toshiba FST Pure 27AF42 CRT TV. Virtua Racing has SVP chip so I guess that maybe why no rainbow banding for that game, but does SSFII have some graphics enhancer chip on the PCB too that could be keeping it from displaying the rainbow banding?

What do you think or know why this is so?

Would have posted here what is rainbow banding ? but didn't want to make anyone upset by posting on an old thread.

[Auzern]

Probably needs a damn good clean on the inside if you haven't used it for years. At least take the top off, get yourself an old toothbrush and some methylated spirits (rubbing alcohol I believe the Americans call it), hold the console upside down and give the connector and damn good scrub. Also get cotton bud (alright Q-tips to the Americans) with said Methylated spirits and give the game pins and damn good rub over too. If you see black on the cotton bud, you have kicked a goal.

Thank you,
This fixed it in December, 2014.
It still works great today as well.

[Xaranar]

So I'm having issues with my Mega Drive 2 currently. It works great, only I'm getting some strange audio interference that seems to vary depending on what is being displayed on the screen, for example if I'm flicking through menu items in a game, it will squeak or buzz upon the highlighted item changing. I've done a little Googling on my own about what could be causing this, and everything from a possible ground loop to video noise could be the culprit, even though I have a Mega Amp installed. I've tested different power supplies, I've disconnected my 32X and Mega CD and tried running the Mega Drive on its own, but nothing seems to affect it. Any help would be greatly appreciated.

[gaggi]

I've stumbled upon an partly broken Sega Mutli-Mega (CDX in the USA) with working CD Player but defective Mega Drive part.
Im about to mess around with it and try to get it working again but i would realy like to know if the Mega Drive part will work with detached CD PCB as it would make testing a lot easyer.
Also does anybody know the pinout of the Connector from Power PCB to Mega Drive PCB?

[Solkia]

Is there anyone who makes replacement contact pads for the 3 button controller?

[GhaleonX]

I have a model 2 Genesis VA1 board that was working for a while and hooked up to a 32x that I s-video modded. At one point the S-video started looking mostly purple, then went out. Afterwards, the Genesis seems to still boot fine, but I can't get video out of it anymore. Audio still works and I can seemingly play a game. None of the caps look damaged, nor do any of the ICs. I was planning to recap the board anyway, but I'm pretty sure that has nothing to do with my video problem so I'd like to figure that part out first.

Is it possible the CXA1145M got fried by the 32x (and just doesn't look it)?

[GhaleonX]

Quick question:

Is there a cap on the Sega CD (model 2) that would prevent the optical drive from spinning?

I just dug mine out of storage and found [what I'm assuming is] electrolytic fluid all over the bottom of the board. While the unit did work, it seemed to have interference on the display, so that's when I opened it up and found the underside of the board in that condition. I changed 80% of the caps (ran out) and the image problem was still there. I got some of the other caps I was missing and now it says it's checking the disc but it does not spin or seem to acknowledge a disc is present. I do see the laser come on if I hold the door sensor down.

Before I adjust any of the pots, it seems rather coincidental that before changing about 7 capacitors the drive was working just fine, but after changing them it does not work.

Thanks for any help.

Additional Info:
PCB: 171-6528C-A
Brand of new caps: Combination of Elna's standard and Elna's SILMAC II capacitors

Notes: I misread the cap at C413 and replaced it with a 16v 10uf like the other 28 on the board. I found a service manual http://www.progettosnaps.net/manuals/pdf/segacd2.pdf that stated the cap value at C413 is 50v 1uf, so I tried that, no change in behavior. Put the original 50v 10uf cap back on and I'm still having the same problem.

Again, the drive was working just fine prior to changing the caps (which I did because of display problems and signs of electrolytic fluid on the board), so considering how suddenly this occurred after a cap change, I'm disinclined to believe adjusting the POTs will have any affect, and would rather not adjust them unless necessary.

[GhaleonX]

Made a video about it https://www.youtube.com/watch?v=fa13hxUrzAM

[Elliotw2]

Speaking of Sega CD, I bought one that seems to work, but the internal RAM gives an error of "CANNOT FORMAT", even after changing the battery. Did I not get the battery in right, is the RAM dead, or is it something else maybe?

[GhaleonX]

I just made my own RGB cables for a model 1 Genesis and I'm not able to get the picture to sync properly. I'm connecting to a Sony PVM-14M4U monitor and when I select RGB with the external sync, I get no picture (if I power the system off then on again quickly, I will see the TMSS screen briefly before it disappears). If I turn EXT SYNC off and remove the sync cable, then I can see the picture but it's all wibbly-wobbly, of course. Do I need a sync stripper, or should I have not used pin 6 (if looking at the back of the Genesis, it's the upper left pin; comp sync)?

Thanks.

EDIT: Ok, so I decided to try adding a resistor to the sync cable and tried a 100 ohm & 330 ohm resistor and no change. Found another resistor lying around and checked it with a multimeter to find it was a 3.3k resistor, and the picture finally showed (with an occasional "cycle"). Grabbed a 1k ohm resistor and looks pretty good so far!


gen1.jpggen2.jpggen3.jpggen4.jpggen5.jpg

[astimp13]

I just received a cd model 1 in the mail from good will and of course it doesnt work(no power). I determined that the green AND red fuse were blown. I bridged/jumped both fuses and it still doesn't work. What are my next steps for fixing no power problem? Also what is the red fuse specs so I can buy a replacement? I already found replacement fuse for the green fuse. I also have a working power supply. Any help is GREATLY appreciated. I really was excited to get my first sega cd and play my first cd game.

[ComradeOj]

I just received a cd model 1 in the mail from good will and of course it doesnt work(no power). I determined that the green AND red fuse were blown. I bridged/jumped both fuses and it still doesn't work. What are my next steps for fixing no power problem? Also what is the red fuse specs so I can buy a replacement? I already found replacement fuse for the green fuse. I also have a working power supply. Any help is GREATLY appreciated. I really was excited to get my first sega cd and play my first cd game.

As far as I know, the model 1 sega cd only has one fuse. It's a green component marked as "F1" on the circuit board.
Here it is circled in green. http://i.imgur.com/ZKbzo.jpg

By "red fuse", are you talking about the component to the bottom left of the fuse in the image? If so, it's a diode not a fuse. It may have shown no continuity in a test, since it only allows current flow in one direction.

I'm not really sure of a definite fix other than the fuse. Try jumping just the fuse and try turning it on for a second. I wouldn't let it run too long like that though. It's possible that jumping the diode caused the system to not turn on. (Or damaged something else)
If it doesn't power up by jumping the fuse, try following where the power goes to see if there is some other dead component.


Here is the schematic for the power input area of the SCD model 1. Maybe it can help you.

[astimp13]

As far as I know, the model 1 sega cd only has one fuse. It's a green component marked as "F1" on the circuit board.
Here it is circled in green. http://i.imgur.com/ZKbzo.jpg

By "red fuse", are you talking about the component to the bottom left of the fuse in the image? If so, it's a diode not a fuse. It may have shown no continuity in a test, since it only allows current flow in one direction.

I'm not really sure of a definite fix other than the fuse. Try jumping just the fuse and try turning it on for a second. I wouldn't let it run too long like that though. It's possible that jumping the diode caused the system to not turn on. (Or damaged something else)
If it doesn't power up by jumping the fuse, try following where the power goes to see if there is some other dead component.


Here is the schematic for the power input area of the SCD model 1. Maybe it can help you.

Thank you for the information! un-bridging the red diode fixed the power issue(along with bridging the green fuse(replacement on the way)). NOW the disc is not spinning when I put a game in(it ejects a little bit later). The tray and eye move fine, but it seems like it doesn't even try to read the game. Any help would be greatly appreciated(I am going to go through the listed steps now on cd repair thread).

EDIT: cleaned laser with alcohol and put a different rubber band in and now disc spins and reads! I have a working model 1!!!! thanks for the help and these threads!