Help with sega turbo PCB

Orion7319

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So I managed to screw up my machine somehow. The game was working until I attempted to install a high score save kit in it. I removed the chip at IC 114 and added a socket for the NVRAM. I have continuity from all the sockets and everything looks good, no shorts or anything. I removed the socket and tried again with a new socket and a replacement TMM2016P-2 chip and no dice. I checked my work and it all looks good to me, so I don't know what I did. I could have flexed the board and broke something or over heated a nearby chip I suppose. Anyway here is a video and a picture of what it's doing. Does anyone have any ideas. I'm pretty novice when it comes to board repair, so I don't know where to begin with this.

https://youtu.be/BDjdYr17ivI
 

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Right where is says IC114 looks like you ripped the trace. (its the thick one)

Thank you for the reply. I forgot to mention that I repaired that trace with a leg I had clipped from a capacitor and I'm getting continuity from the top of the pin in the socket to where that trace is supposed to go.
 
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These are some pictures of the chip and socket installed. I tried another z-80
Just for kicks and that didn't change anything.
Edit:
I asked in another thread, but I might as well ask here as well. Does anyone know of anyone who works on Turbo boards other than El Dorado games?
 

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Your turbo went turbo!!! I just went through the same thing when installing the high score save kit. Is it the kit from Matt Osborn at scoresaves.com? If so he was very helpful at working out the problem with me. You probably just need the additional romms from him. The kit came with 1 rom and a nvram. When I installed them my turbo was doing the same as the image s u posted. If u put the original rom back in does work again? Let me know if I can help, or reach out to him. His kits are great, just did my Gyruss too.
 
Your turbo went turbo!!! I just went through the same thing when installing the high score save kit. Is it the kit from Matt Osborn at scoresaves.com? If so he was very helpful at working out the problem with me. You probably just need the additional romms from him. The kit came with 1 rom and a nvram. When I installed them my turbo was doing the same as the image s u posted. If u put the original rom back in does work again? Let me know if I can help, or reach out to him. His kits are great, just did my Gyruss too.

Thanks for the reply! I really appreciate someone trying to help me get this game working again. Yes that is the kit I got. I had to cut the legs off the chips in order to get it off the PCB. It was a 2128RS and I replaced it with a used TMM2016P. That didn't fix the issue at all, so I assumed I broke something. The rom was working for free play. I didn't have an issue until I tried to put the NVRAM in. Perhaps I need to try another 2128RS? What sucks is that I had basically given up on this board set and literally just bought another complete board set on eBay for $80.00. But if I can get this one working again as well, that would be awesome! Thanks!
 
I would really just reach out to him, And have him send you the three roms that you need. That should do the trick, mine works perfect. As for the other board you just bought that's a good price on the board and it's always good to have a spare. Good luck!
 
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cc99931bc1bc7eb372343ac3d70cbc85.jpg
 
Here's a photo of my board just to reference. The two ROM chips in between the one Mark turbo HSFP and the NVRAM we're the ones I had to replace. When it was in this configuration the screen was doing exactly what yours is doing in the video. When the other two were replaced from the one Matt sent me it worked perfect. Good luck.
 
I would really just reach out to him, And have him send you the three roms that you need. That should do the trick, mine works perfect. As for the other board you just bought that's a good price on the board and it's always good to have a spare. Good luck!

Thanks! I reached out to Matt, I'll see what he says. Yes I agree with a game like Turbo that no one really seems to work on, it's good to have another board set. This one has all three boards in the stack as well as the LCD display, so it was a good deal.... even though my wife doesn't seem to think so! Lol!
 
I just read your post about your restore, what a project! You really resurrected that turbo from the dead. You can't quit now you're almost at the finish line! I'm sure you will figure it out, good luck.
Also, the sticker you had made up for the gearshift there, did you just bring that to a local print shop and they were able to make it? Mine is missing and it looks much nicer with that on there, would like to get one. Let me know, thanks.
 
I just read your post about your restore, what a project! You really resurrected that turbo from the dead. You can't quit now you're almost at the finish line! I'm sure you will figure it out, good luck.
Also, the sticker you had made up for the gearshift there, did you just bring that to a local print shop and they were able to make it? Mine is missing and it looks much nicer with that on there, would like to get one. Let me know, thanks.

Thanks! I'm not giving up, but I do have to finish this up or get to a point where I can stop for a bit as the wife is getting pissed! Lol! The sticker, yeah I took that picture I found here and vectorized it in illustrator and then printed it on my printer, just to see how it looked. I sent the file to Etienne to have him print it on Aluminium and I'm just waiting for him to do a run. He has the file and if you contact him I'm sure he'll include you in his next run.
https://www.easywebshop.com/arcadedecals/
I've spoken with Matt (great guy) and I have a few things to try. It doesn't look like my work was bad, but it's also looking like this board is having some issues that are a bit much more then incorrect roms. We will see if I can get this board working, but right now that's not looking so good. Hopefully the new board stack I ordered will work.
 
Turbo has several different encryption modules in the wild. You have to make sure that you get the correct rom sets that match the encryption module of the cpu.

The rom that Matt gave you was most likely encrypted with a different key than the encryption key of your cpu module, and doesnt match your other two roms either. You will need all three roms to be matching.

I went through the same thing with mine. I have a rom burner, so I was able to re-burn the other two eproms with various rom versions from MAME until I got the correct ones and the game worked.
 
Turbo has several different encryption modules in the wild. You have to make sure that you get the correct rom sets that match the encryption module of the cpu.

The rom that Matt gave you was most likely encrypted with a different key than the encryption key of your cpu module, and doesnt match your other two roms either. You will need all three roms to be matching.

I went through the same thing with mine. I have a rom burner, so I was able to re-burn the other two eproms with various rom versions from MAME until I got the correct ones and the game worked.

I think I have an unencrypted rom set though. Are there different unencrypted rom sets? When I put all three original roms back in the board it still won't boot. Perhaps it might be a good idea to get the full set of roms from Matt. He thinks the game isn't running any code at all because the video is scrolling sometimes and not always a static image of garbage. I think if my new board set works (which looks like its unencrypted as well as it doesn't have the metal can on it) I'll try swapping all three roms on to it and see what happens as I suppose it's possible the roms are somehow now toast. I should probably replace all the sockets for those as well. Other then the roms and the CPU, does anyone know of any other chips that I should be looking at when the board won't run any code? I think it's got a z-80 processor in it but I'm not sure what version of z-80 I need either as the lettering on mine wore off.
 
It's not the roms. I bought another board set and it would boot to a screen with garbage as well. I swapped the unencrypted roms from this one to the newly acquired one and it booted up, so the roms are all good. Also the new audio PCB was working fine for about 5 minutes when it abruptly died. It has no hiss or hum or anything. It's like it's not getting power. Does anyone know if that would that most likely be a rectifier or a cap or something else on this board?
 
Does your Turbo have a switching power supply in it? Mine did, and it was bad. When I first got my Turbo the board would boot to garbage as well. I tested voltages at the board and it was very low. Replaced the switcher with a new one and it came to life. Could be that your switcher is bad.

If your roms are working in another unencrypted board set, then your problem is either voltages or some other failed component on your board.

Probably worth it to triple check your work around the socket you installed, and make sure to buzz out continuity on every single trace, pad, and via. Also, good idea to remove every single chip, clean the pins with an eraser (these are usually totally cruddy on Turbos), check for bent legs, and reseat properly.

If that doesn't resolve it, then I think it's time to break out the logic probe and compare to your new good working board set.
 
Does your Turbo have a switching power supply in it? Mine did, and it was bad. When I first got my Turbo the board would boot to garbage as well. I tested voltages at the board and it was very low. Replaced the switcher with a new one and it came to life. Could be that your switcher is bad.

If your roms are working in another unencrypted board set, then your problem is either voltages or some other failed component on your board.

Probably worth it to triple check your work around the socket you installed, and make sure to buzz out continuity on every single trace, pad, and via. Also, good idea to remove every single chip, clean the pins with an eraser (these are usually totally cruddy on Turbos), check for bent legs, and reseat properly.

If that doesn't resolve it, then I think it's time to break out the logic probe and compare to your new good working board set.

My switching power supply holds a constant voltage. When I first got the machine someone had it cranked all the way up though. I do have it set around 5.25v as I am getting a slight voltage drop and it's coming into the board right at 5V this way. Also when I drop it down to 5V at the switcher the gas pedal doesn't work right or consistently. I noticed that the chips I measured were at 5V or in some cases down to 4.5v or so. Perhaps I should adjust it up a bit more? I have cleaned and reseated the roms several times now, checked my work with continuity about 10 times and it seems fine. I resocketed the z-80. I don't own a logic probe but I suspect it might be time for me to get one! Your right I have something to compare it to now and I just might be able to figure it out with a probe now! Thanks for the reply, it was helpful!
 
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