What's new

mR_CaESaR

Champion
Joined
Jul 10, 2018
Messages
1,267
Reaction score
1,772
Location
Sydney, Australia
Here I am with another project - I'm a sucker for punishment! :D

A few weeks ago, I was given an ad on Gumtree for a couple of Blast Cities located in Newcastle. I was umming and ahhing about getting them as I really don't have room. Mrs said, "just buy and fix them up, then decide what you want to do, keep both, keep one and sell another cab in your garage, or sell both, you know you love to bring things back fro the dead". Soon after I msg'd the seller to pick up the coming weekend.

Unfortunately I didn't have a vehicle to transport it, so I asked a mate to use his car and off to the local 7-Eleven we went to hire out a trailer.

joBme4Zl.jpg


The ad for the Blast Cities were NOT WORKING, and of course, there's nothing more I love than bringing cabs back from the dead - all dependent on Joey. If Joey can bring them back, great, if not, I'll sell for what it cost me to get to my house. Here they are loaded up

apZ1ICQl.jpg


Lucky for me, the seller decided to give me a whole bunch of chassis and I took the opportunity to grab whatever he would give me. In the end I got 2x MS2931 and 3x MS2930 (2 of which were in side the cab) and a Wei-Ya chassis that I was advised was a drop in

H9TuggSl.jpg


After the drive home, I left it as it was and started sussing out what I was in for the following day..

qr9Cj06l.jpg


One cab appears to be worst for wear than the other, multiple areas have paint flaking off - I am not repainting these cabs, they are just too much work, so I will embrace the war wounds.

YNEeKssl.jpg


Hlxa7STl.jpg


Eg3uewil.jpg


Never worked on a Blast City before, I had no idea what was what and this spaghetti of wires was quite intimidating, I had a trusty multi-meter, but fortunately, the other cab was quite intact

QQhapejl.jpg


After a solid hour of detangling wires and putting some cable ties, I ended up with something a little more respectable. This cab unfortunately is missing a JAMMA loom.

FGimEVgl.jpg


Decided, I'll give it a good clean once I have everything working.

I reached out to Joey and he advised that he wouldn't touch any chassis that had black goop. Of the 5 chassis I got, only 2x were black goop free (a 2931 and a 2930).

Removed the monitors out of the cab - WHAT A PITA IT WAS!! Compared to other cabs I've worked on, the Blast City is by far the most painful cab to get the monitor out.

Eventually got them on the floor :)

zVszdrhl.jpg


It was a shame that both tubes had some burn in with one monitor having worse burn in than the other.

Now the monitor was out, I quickly ran some test to see what the go was with them and one had no image, just a blue screen.

5Ze3Sorl.jpg


Off to Joey they went.
 
Joey advised that he worked on both chassis and was able to bring them back to life so they were operational. He also stated that he used the last 2931 flyback he had so that was a bonus.

They arrived and looked brand new compared to what they were when they were sent to him.

MS2931

Ed3xzazl.jpg


MS2930

62xXIV4l.jpg


I couldn't decide which chassis to test first, so I decided to go the 2931. As soon as I connected it, I was in awe of the picture quality - but something was "off". After trying to adjust the display, the best image I could get wasn't a full screen image, it appears to have been zoomed in by about 20%

PSLyLiMl.jpg


I reached out to Joey and he asked me to try and make adjustments on the B+ pot


As you can see in the video, the image slightly adjusted - but nowhere near enough of what I am expecting.

So I decided to work on the other chassis, the 2930.

Connected it all up, and upon turning on, I got background image, but I couldn't get any red or green on the image and no amount of turning the gain pots changed the image.

TVOOCiwl.jpg


By this point, I was extremely frustrated with both chassis and I've always heard how much of a PITA they were. Reached out to Joey again and he said to check the neck board for some loose transistors, they seemed fine, so the only thing I could really do was to send the chassis back to Joey for further inspection.

I was ready to cut my losses and call it a day......

But me being me, I am quit stubborn and I don't like to wave the white flag so easily so I thought I'd do some trawling on the interwebs :D :D

After reading numerous threads, I believe I came to the conclusion that the flyback being used on the 2931 is not an original nanao. Whilst new, it wasn't a complete 1:1 and it seemed to point to that direction. So I decided to try my luck and roll the dice.

The plan was to do some electronic surgery :) remove the flyback from the dead 2931 and put it on the newly refurbished one to "test" the theory! Never worked on CRT's before at this level, I was packing s**t!

10 minutes worth of desoldering, I was able to get the flyback off both 2931's. I was a little weary about the flyback as there appears to be a break on the anode cable.

SnxZ8Hdl.jpg


I still went to test - curiosity got the better of me.

After installing the flyback and the chassis back to the monitor, I turned it on - expecting arcing, or a loud hum, noise.. I was greeted with the following image

N0lRLEKl.jpg


WINNER! so I thought!

The original flyback clearly shows the image is much smaller than the other flyback I had. I started adjusting the image, and then a few funny things started happening which got me scared so I turned it off.

Check it out from 47 seconds...


Called it a night as I was a little too scared :D

The following day, I spent some time reading through more threads and with the help of djcalle, he pretty much confirmed that the MS2931 and MS2930 share the same flyback. I have 2x dead MS2930's but may have working flybacks.

So I decided to once again desolder the flyback. Nice and clean!

uYuMeEdl.jpg


Flyback cleaned and dusted - it was at this point I realised why some monitors may potentially die. All the black goop appears to have gone on a pin on a flyback and I couldn't get any form of continuity from the pin to the top where the black goop was.

1beOjpol.jpg


Installed the flyback and kept everything crossed and hoped that nothing exploded on me when I put the power on.....

Voila! Perfect 15khz full screen image!!

qxhcRWVl.jpg


I let the game run on for a lot longer and I got 30 minutes without any funny zooming in or anything like in the previous video


Big massive win for the 2931. Next up tackle the 2930.
 
So this post will be about the 2930!

As mentioned in the previous post, when I plugged in the 2930 all I got was a blue image, I couldn't get any Red or Green bias dialled in. When I reached out to Joey who said check the transistors which I did and couldn't find anything obvious. Rather than sending it back to Joey, I thought, I'd try my luck with changing the neck board with the other two spare 2930's.

Simple enough mod, desolder two wires from the flyback and unplug a couple JST connectors.

When I fired her up, I was greeted with a red and green! Of course there's no blue!!

Ux8hARfl.jpg


So I tried my luck with the third and final neck board....

VOILA!! WE HAVE COLOUR

ROEXFmwl.jpg


Whacked on a game and she came out all good, obviously needed to dial in the horiztonal/vertical size and positions.

D9JF0a3l.jpg


So 15khz is now running perfectly, I thought I'd try my luck with getting 31khz...

First attempt at using a DC didn't go down too well.

GdJmZZvl.jpg


As you can the image is waaay too narrow and my horizontal pot was already maxed out.

Reached out to a few people I knew that had the blast city and a 2930 who don't seem to have this issue. So I had to trawl the interwebs further :)

I found a jumper on the chassis that stated "narrow" and "wide", so I tried swapping it around

O76g875l.jpg


That didn't work. I then tried the 2931 to see if it was experiencing the same issue with 31khz, no such issue as I was able to adjust accordingly.

NqZodPWl.jpg


I then read a post on Arcade otaku about changing a horiztonal limit. After looking for about 5 minutes on the board, I tried changing "H.S.L" and saw it improve so I maxed it out to get full screen. I later found out this pot stood for Horizontal Size Limit

KkoaweZl.jpg


Working perfectly with a Naomi! Look at that buttery image! :)

A74eSY6l.jpg


Monitors are now working, so it's time to work on the cab itself, test for power and what not as they haven't been tested at all yet.
 
I sort of hate you for finding those cabs. Not that i'm anywhere near there, just get this evil hatred feeling.... but in a friendly kind of way :)

A blast city is a cab i want to get one day, not that i have anywhere to put one.

Look forward to more updates!
Don't worry, you're not the only one! I always give @mR_CaESaR crap about how cheap he gets all of his cabs for... Super envious as well! :D
 
I sort of hate you for finding those cabs. Not that i'm anywhere near there, just get this evil hatred feeling.... but in a friendly kind of way :)

A blast city is a cab i want to get one day, not that i have anywhere to put one.

Look forward to more updates!
Ironically, a friend from Melbourne was the one that pointed me to them... I ummed and ahhed on them for about 4 hours before the Mrs said to me... "just buy them and fix them up, you love doing that crap"

Thing is, I haven't been a fan of them.. and I know why I've never had one.. the chassis drama has been a PITA. Parts are a pain, but I will do everything I can to get them working again :D :D (that's just my stubbornness). Then I'll see what I end up doing going forward

Don't worry, you're not the only one! I always give @mR_CaESaR crap about how cheap he gets all of his cabs for... Super envious as well! :D
:D :D :D

The beauty of buying "broken" - problem is, it could be a "cheap" fix or an expensive fix. And I'm only confident to buy Astro's cheap because we have Jomac. Everything else is easy. With these cabs, Joey really made an exception as he doesn't normally do these chassis - pita that's why LOL
 
Now I sorted out the monitors, it was time to start making my way onto the cab and seeing what else needs to be fixed.

First off the rank was power. I needed to figure out what was the status of the power.

This cab is 100v, so I purchased an external step down transformer from ebay as my test rig. I have plans to do internal step down at a later point in time (if I can be bothered
biggrin.gif
)

Plugged the psu into its respective spots in the I/O, plugged the JAMMA harness with a pandora's box as a test pcb... flicked it on and... nothing! No fan, no light, no sound, nothing! Boo!

Went over the cab again, made sure the "kill switch" at the door was pressed (even made the adapter for the kill switch), checked and replaced the fuse on the psu, still nothing.

LAHnNgll.jpg


Made sure 110v was coming out of the step down - check!

X7ZO17yl.jpg


Unfortunately, I couldn't find the reason it wouldn't power on. I gave up for the night
biggrin.gif


The following day, I was advised to check the Blast I/O if it was getting 100v, since everything has to go through the I/O before it can be fed back to the PSU. I started pronging around to find the 100v line and I eventually found where the 100v was and realised - wtf? It went nowhere!

fUjURb5l.jpg


So I did what everybody should always do first - RTFM!
biggrin.gif
biggrin.gif


I found exactly what that connector did when I read the f***ing manual
biggrin.gif


LcmbmO3l.png


It's clear in the manual, there's a connector to loop back the 100v, so I made the little connector.

VkmX7g3l.jpg


The moment I connected that, things started to work as expected
smile.gif



After getting power to the cabinet, I tested the voltage of 3.3v, 5.0v and 12v. Both 3.3 and 5v needed to be dialed back but I didn't realise the 12v didn't have an adjustment pot on the blast!

5v right on 5.00

x4z2oN9l.jpg


3.3v right on 3.3v

v1RwPSCl.jpg


12v is slightly under - hope this doesn't cause issues.

t27zv6yl.jpg


The last thing to check are the speakers - I've heard a lot of issue with the blast speakers, especially the challenges involved when you have to find a replacement.

I'm lucky to say both speakers appear to work - I haven't bothered taken them out as I don't really want to split the whole cabinet in half to get to the speakers.

 
yep! I spent a good hour the first night trying to figure out wtf was going on.... then it took me 20 minutes after reading the manual and tracing back with a multimeter LOL
 
So this post will be about the 2930!

As mentioned in the previous post, when I plugged in the 2930 all I got was a blue image, I couldn't get any Red or Green bias dialled in. When I reached out to Joey who said check the transistors which I did and couldn't find anything obvious. Rather than sending it back to Joey, I thought, I'd try my luck with changing the neck board with the other two spare 2930's.

Simple enough mod, desolder two wires from the flyback and unplug a couple JST connectors.

When I fired her up, I was greeted with a red and green! Of course there's no blue!!

Ux8hARfl.jpg
My guess is a broken solder joint on the neck connector socket. I had that exact same issue and reflowed all the solder joints on that socket, blue was restored afterwards.
 
My guess is a broken solder joint on the neck connector socket. I had that exact same issue and reflowed all the solder joints on that socket, blue was restored afterwards.
If the 3rd neck board swap didn't work, a reflow of that whole area would've been my next attempt.
 
Since the first cab is now confirmed operational, this cab seemed to be the better condition cab so I gave it a good clean!

It's amazing what some elbow grease and a magic eraser can do! I personally like some "war wounds" on the cab so I decided to keep this particular cab as my shmups cab

Some before shots

hWTbHZMl.jpg


XUiZV7gl.jpg


FoEMO1jl.jpg


eNGTXCRl.jpg


Some after shots

nGQQxj3l.jpg


VBsDcjYl.jpg


1y3Qdqgl.jpg


p36vm2Ul.jpg


Once all the dirt, grime and stains were gone, I spent a decent time on hand cutting and polishing the cab using some septone fibreglass boatcare products

zUMMyd3l.jpg


After all completed, she's looking clean and shiny!

g85eomcl.jpg


The control panel has come good too

hfkIu47l.jpg


Will start installing the monitor and parts back into place
 
I hit a snag the other night
frown.gif


I started cleaning the second cab and as I gave it a good wipe down, the paint just started flaking off, and it go worse and worse as I cleaned more..

The initial thoughts were "touch up" but what started like this...

Hlxa7STl.jpg


Ended up like this after some elbow grease

gJ65WQTl.jpg


Some flaking...

vQTjeadl.jpg


After a wipe down it looked like this - so I just started sanding

IRvPr6Fl.jpg


And then I decided, there's no way I could "touch" this up without a proper colour match, so for those that remember my Naomi Universal project and me saying in the first post " I am not repainting these cabs, they are just too much work, so I will embrace the war wounds", it looks like I'll be painting this mofo :D :D

I'll keep this cab and get rid of the other "better" condition cab - I really am hating this cab of all the cabs I've worked on lol

An hour later, the cab is officially stripped out! (took me an hour, since I've never stripped a blast before and there were so many JIS screws - which I f***ed two up and needed to drill out)

6iOJY6Yl.jpg


I am hoping this doesn't end up taking me 5 months like the universal - it shouldn't as there's no rust damage or patching I need to sort out. It's all in the prep work!

I also realised why the speakers sounds so crap when I tested it...

kq2mvFsl.jpg


The foam has rotted away! And of course, there's no "easy" replacement speakers for this cabinet - unlike the astro's or naomi universal... the hate for this cab grows daily! :D :D
 
Managed to get some a few hours worth of work on the weekend.

First had to spray the decal residue with some IPA

kjJME9Fl.jpg


The next 3 hours were spent on hand sanding/feathering on all the areas that had flaking.

wgPZKicl.jpg


wRq6X1kl.jpg


zI4DHJ9l.jpg


pzzd1NRl.jpg


Gave it a good clean with wax and grease remover before putting on the first coat of primer!

tzyTIGRl.jpg


Can already see the massive difference in this area

5MzQflzl.jpg


And of course... I ran out of primer as I was getting to this side.. *facepalm*

IXfUu4Wl.jpg
 
Not much has been happening, we've had terrible weather the last few weeks and I just cbf atm.. lol

The only thing I've worked on are the speakers.

I purchased these speakers online https://www.parts-express.com/aurasound-ns2x3-184-4a-2-x-3-extended-range-driver-4-ohm--296-256

They are slightly bigger than the original stock speaker, but it's the closest thing I can find to a drop in.

Old vs New

6Cg3rkHl.jpg


4FUVDhnl.jpg


Foam installed where the old one was

L0RHY2vl.jpg


Caulked some of the gaps at the front where the existing bracket was

eYtSYX3l.jpg


A quick test and at least I know she works. They definitely sound a lot better than what they were and they will definitely be sufficient for arcade games, but they're no Namco Noir - which to me, has become my benchmark for Candy Cab speakers :)

 
4FUVDhnl.jpg


Foam installed where the old one was

Amazing thread! I'm also restoring a Blast although I'm much less experienced. Can you give information on the dimensions and size of this foam you're using? I'm planning to also use the same speakers and apply caulk as well to seal any air gaps.
 
When you removed the speakers from your blast, was it difficult to also remove the speaker grills? I assume they are glued in or something? Do you think you'll be able to re-insert them and what is your plan for that? The speaker grills on my Blast appear to have been pushed in a bit probably from some careless person in the arcade. If the risk is too high I may just leave them as is but I would much prefer to get them looking flush with the cab again.

EDIT: After some searching, I managed to come up with this over on OA: https://forum.arcadeotaku.com/viewtopic.php?t=29408

Looks like others have discussed this issue, but I couldn't find anyone talking about success/failure afterwards. Only what they planned to do in advance.
 
Last edited:
Wow, it's been 4 months since I last updated!

I haven't really had much motivation to finish it off, I had one cab in its place with the rest of the cabs which made me really delay the finishing of the other cab.

With that said, I recently sold off one blast so I needed to get a crack on the other one. I'm gotten to the point where I don't care any more about the paint job LOL. I've gone through about 10 coats doing the two major pieces with sanding in between as I either can't "get the right finish" or it ends up having some paint running because I'm getting too impatient. The last coat I did is the final coat for the two shells (if there's runs, there's runs, if it's uneven, it's uneven). I'm done, I just want to build it and get it done.

The paint has dried, but I'll wait a few more days for it to cure. On the photo, it doesn't look too bad, but on closer inspection, there's definitely a run or two - oh well!

99MLbFFl.jpg


These pieces aren't too bad to paint, definitely a lot easier to get a decent finish than the two shells :)

0ULkV8yl.jpg


In between paint coats, I decided to mod the coin mech that I purchased from YAJ. Since it accepted ¥100 coins, I knew the Capcom tokens I had were slightly bigger, but also knew these coin mechs should be able to have some sort of adjustment to allow for slight variations.

Capcom token, next to ¥100 and next to a 10 cent coin (AUD)

kT71odKl.jpg


Here's the first step

7CipI2xl.jpg


Second step

vOYdgU8l.jpg


Last step

E98qufPl.jpg


Video of it all working


Hopefully in the next week or so, I can at least put the two shells together and start the rebuild process!

I hope I still remember how to re-install everything, I was supposed to use the other blast to copy, but now that's gone, silly me didn't take proper pics and what not - I'm sure I'll figure it out :D
 
Back
Top