Blast City Club

[Pasky]

Again, if someone with a MS 2931 chassis please tell me the value of C230 and C233 I'd appreciate it. Arcade Otaku lists them as 22uF, but I pulled them both off and one of the original caps is 2.2 uF not 22 uF, but I don't know which is which.

I would really appreciate it, thanks.

 

[kuze]

Again, if someone with a MS 2931 chassis please tell me the value of C230 and C233 I'd appreciate it. Arcade Otaku lists them as 22uF, but I pulled them both off and one of the original caps is 2.2 uF not 22 uF, but I don't know which is which.

I would really appreciate it, thanks.

I'll try and check into this for you tomorrow bro

 

[Pasky]

I'll try and check into this for you tomorrow bro

Thanks!

 

[kuze]

MS2931

C230 - 50v 2.2uF
C233 - 50v 22uF

https://imgur.com/a/SN3KBQX

Maybe you can get the cap map at AO updated when you get a chance? If not, LMK and I should be able to take care of it.

Disclaimer: This is from my only MS2931 chassis and it's broken, but as far as I know the caps haven't been changed from the originals.

 

[Pasky]

MS2931

C230 - 50v 2.2uF
C233 - 50v 22uF

https://imgur.com/a/SN3KBQX

Maybe you can get the cap map at AO updated when you get a chance? If not, LMK and I should be able to take care of it.

Disclaimer: This is from my only MS2931 chassis and it's broken, but as far as I know the caps haven't been changed from the originals.

Thanks dude! Surprised no one else has ever mentioned this.

 

[kuze]

Thanks dude! Surprised no one else has ever mentioned this.

Glad to help! Hope you're able to fix the issue you're having with your chassis.

If not you might consider sending it to Sharp Image Repair or PNL Video and have them take a look.

 

[ChuChu Flamingo]

Might have been fixed from the factory/revision. Old capacitors values are the gospel whenever changing stuff since factory fixes can and have happened.

Don't quote me but I swear i've read somewhere before that some of these capacitors might have been underspec'd from the factory. Would kinda explain the reliability of them.

 

[Pasky]

Might have been fixed from the factory/revision. Old capacitors values are the gospel whenever changing stuff since factory fixes can and have happened.

Don't quote me but I swear i've read somewhere before that some of these capacitors might have been underspec'd from the factory. Would kinda explain the reliability of them.

Seriously doubt that. C230 goes to a CXA2055. It's the Pre-amp and C230 also goes to pin 27 on that chip which is the composite sync output. I doubt it'd be under spec'd. It also explains why I have a damn rolling picture on my tube after recapping. 2.2 and 22uF seem like a typo 100% especially considering Kuze's was also a 2.2uF

 

[Pasky]

So out of necessity I bought a Makvision 27". I know all about the reputations of these CRT's, they're rebranded Weiya's the picture isn't great etc... It's unfortunate because the only other monitor I could find to replace mine they wanted $1300 for.

So I'm gonna attempt to keep working on my current one, the tube is good but the chassis is having issues, either find another ms2931 or fix this one at some point, the flyback is still good so other devices can probably be replaced and fixed. In the mean time I'll have the Makvision. So I know the bezel won't fit but does it mount correctly or am I going to have drill some holes? What do I need to know about fitting the Makvision in the blast, I heard you can dremel the bezel or something along those lines so I may pick up a spare blast bezel and modify that but I don't know what is involved. Any advice would be appreciated. Thanks.

 

[kuze]

I can't say from experience but I'd expect needing to swap the monitor frame to the new tube and possibly backmount to get it to fit right. There will still be a bit of a gap between tube and bezel.

 

[Pasky]

Just got the monitor in today

The mounts don't fit the blast bolts at all. Not sure how I'm going to go about this as I'd like to keep the original monitor and work on it. Anyone else ever fit one of these Makvision tri-sync's in a blast city cab before? I know some people on this board have. Would appreciate any advice.

 

[radiantsvgun]

Just got the monitor in today

The mounts don't fit the blast bolts at all. Not sure how I'm going to go about this as I'd like to keep the original monitor and work on it. Anyone else ever fit one of these Makvision tri-sync's in a blast city cab before? I know some people on this board have. Would appreciate any advice.

This isn’t what you want to hear, but a lot will swap frames. It’s time consuming and a pain in the butt to do, but probably the only way to make it work. I did a similar swap with a pfx in the Astro and I had to use the Astro mounting frame.

 

[Pasky]

Ya hmmm, I'm gonna take the top and bottom off of the makvision frame when I have some free time this weekend and measure it, see if there's enough meat to drill some mounting slots.

 

[todosnk]

Blast City sound - help!

Hey guys, I'm seeking for some advise here.

My monitor (or chassis, I am unsure) since a few days ago starts making some noise. I made a small video here:

https://photos.app.goo.gl/6tgn2XUQ6xRXtbnF7

After a few minutes, the noise drops and it seems to be almost gone, but still I can hear it a bit and I have no idea where is it coming from, I thought maybe covergence strips might be loose but its not the case.

I have a PC inside the cab but the noise comes as soon as I turn on the cab, even with the PC powered off.

Also I can see some black liquid in the middle of the chassis out there. I guess that is normal because its tight, nothing that seems to have been dropping recently at all.

But I am concerned on both, could anyone please guide me a bit whats going on to my beloved Blast City? I am not technical but I'll try my best to understand

If this has some fix, I am really appreciating how to best proceed here. I hope I don't need to buy a new one though

Any advise please?

Thanks a lot!

 

[Kid Panda]

I can't see the video but the black goop is non conductive. Little research could have shown you that. If the "chassis" is making a whine noise it's the flyback. Try loosing the screws that hold the chassis to the frame first, that technique works sometimes on a New Net City.

 

[todosnk]

Thanks for the reply!
I gave it a try, unfortunately the whine noise still persists.

 

[Westcb]

Thanks for the reply!
I gave it a try, unfortunately the whine noise still persists.

I have gotten rid of the noise on a couple blast chassis by pressing toothpicks into the core of the flyback. Usually there is a crack and the vibration is what causes the sound. By probing around and applying a little pressure you will be able to see if the noise goes away. Once you find the sweet spot a little hot glue will usually hold it in place. Don’t worry a wooden toothpick will not zap you just don’t go jabbing or touching other parts while you attempt this.
If you decide to google for it lookup flyback whine toothpick trick you should find some results. Another place I have found the noise is on the copper windings around the neck of the tube.

 

[NEgO MANIAC]

I've had a miserable time keeping the NANAO monitor going in my Blast. I've had the chassis go out several times for different things. It's been re-capped. I was wondering if the monitor uses a "field ground" connection. I know there is a ground through the JAMMA harness, but I don't recall a field ground on the frame. If there is one were is it located? If not, would it make sense to add one? Every American wood cab I have has this.

 

[todosnk]

I have gotten rid of the noise on a couple blast chassis by pressing toothpicks into the core of the flyback. Usually there is a crack and the vibration is what causes the sound. By probing around and applying a little pressure you will be able to see if the noise goes away. Once you find the sweet spot a little hot glue will usually hold it in place. Don’t worry a wooden toothpick will not zap you just don’t go jabbing or touching other parts while you attempt this.
If you decide to google for it lookup flyback whine toothpick trick you should find some results. Another place I have found the noise is on the copper windings around the neck of the tube.

Thanks mate! I'll try it out but from what I read doing a search in google, this could well make the trick

 

[the7k]

Finally found a new place to set my cabs up at. Got me in the mood to make a new Blast City marquee for Third Strike.

Based it off of the SF3:New Generation flyers: https://flyers.arcade-museum.com/?page=thumbs&db=videodb&id=1099

Edit: I think I like it better without all the extra info. Not sure.

 

[The_Chosen_One]

Definitely better without all the extra stuff, looks much cleaner.

 

[tonyt76]

Hey guys i'm trying to use a Sega 838-13683-93 Rev B JVS to Jamma for my Naomi in my Blast.

I have CN8 on the Blast wired to the 14pin input correctly. All I am getting in the Naomi I/O test menu is buttons 6,7,8.

Has anyone successfully gotten buttons 4,5,6 to work with this JVS adapter?

 

[NERDtendo]

Hey guys i'm trying to use a Sega 838-13683-93 Rev B JVS to Jamma for my Naomi in my Blast.

I have CN8 on the Blast wired to the 14pin input correctly. All I am getting in the Naomi I/O test menu is buttons 6,7,8.

Has anyone successfully gotten buttons 4,5,6 to work with this JVS adapter?

Let’s see pictures of how you have both I/O boards and the NAOMI hooked up.

 

[cornerstone]

Is there a monitor repair flowchart available? I feel like I’ve read about one somewhere.

My Blast is playing blind currently.
-PSU starts up, but is in need of a cleaning and new fan
-Marquee lights up
-Movement of SCREEN pot and a few other video pots will produce some faint sort of sound like it’s changing something
-No “clicking” when cab starts up
-doesn’t seem to have any static buildup on monitor after being on for a while
-I’ve reseated I/O and monitor Molex connections
-I haven’t completely checked grounding but don’t think there’s any loose cords
-ceramic chassis fuses are old, so I’ve ordered two new ones, have to wait on that

Is there any way a bad PSU would run power to jamma board and marquee but not allow monitor to come on?

I feel like this is more of a bad chassis, but it was working a few days ago before transport. Possibly something came loose?

This is the manual sync chassis

 

[skate323k137]

Hey guys i'm trying to use a Sega 838-13683-93 Rev B JVS to Jamma for my Naomi in my Blast.

I have CN8 on the Blast wired to the 14pin input correctly. All I am getting in the Naomi I/O test menu is buttons 6,7,8.

Has anyone successfully gotten buttons 4,5,6 to work with this JVS adapter?

4 and 5 connect to the JAMMA edge. You use the normal loom for P1 and P2 for those buttons. Button 6 from the extra connector.