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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.




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




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




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




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.








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




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.




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 :)




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.




Off to Joey they went.

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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.










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%




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.




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 loses 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.




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




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!




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.




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!!




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.



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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!!





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







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





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.





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





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.





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





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





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.



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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.




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




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!




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




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




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




3.3v right on 3.3v




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




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.



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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














Some after shots














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





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





The control panel has come good too





Will start installing the monitor and parts back into place

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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...




Ended up like this after some elbow grease




Some flaking...





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





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)





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...





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

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Managed to get some a few hours worth of work on the weekend.


First had to spray the decal residue with some IPA





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














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





Can already see the massive difference in this area





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



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  • 4 weeks later...
  • 2 weeks later...

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








Foam installed where the old one was





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





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 :)


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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








Foam installed where the old one was





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





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 :)



Even if though the speakers are bigger, do they drop-in okay?

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  • 4 months later...

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!





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





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)





Here's the first step





Second step





Last step





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

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  • 2 weeks later...

This weekend that just passed, I set myself the goal of "just getting the shell screwed in to the base" as the shells had "dried*"


*more on that later.




The wiring deceivingly took WAAAAY longer than I expected as I decided I would take out all the old clips and put some double sided gorilla tape on them so I could reuse them... some 3 hours later I ended up with this - and it still wasn't done complete!




Once the wiring was done, I thought yeah why not, let's put the two shells back together. Voila!




Remember the "dried" comment earlier? Well there's a couple of spots that have my fingerprints on it as I pressed on it too hard when I was screwing the shells back together - I'm guessing 1 week in the garage hasn't really "cured" the whole paint job - fmd. I wasn't going to sand it down and re-paint - I'm well and truly over it! I just want to play on this cab! The show must go on :D but it was well past 1am so I called it a night.


Saturday morning came around and I thought "I've done my goal of putting the shell together, why not clean the marquee, install the led and test the bezel out in Tate mode"


Marquee cleaned up and installed the DDP artwork from sellsells2000 (will eventually change to Esp Ra.De or if he makes a Futari one)




Marquee and bezel installed! Not too shabby! Was very happy with the results




That was pretty much my Saturday as I had to adult :)


Sunday morning... I thought,"only thing let is really the monitor, I've got a spare few hours in the morning, why the hell not!"


What an absolute debacle getting the monitor lined up properly to get those bolts exactly in place. I had a 30 minute attempt, but my arms needed to rest. Spent another 30 minutes trying to line it all up and eventually got there. The geniuses (or is it genii?) at Sega decided to make bolts shaped in a certain way and can only go in a certain way - why not stick to circular like the astros?! Anyway, the monitor was finally in, wired her all up, triple checked the connections, crossed my fingers and hoped for the best as she was being turned on for the first time!




It's aliiiiiiive!!! :D :D


Then I noticed only ONE speaker was working! What?! Are you f***** kidding me?!?! I haven't done anything since November, how the hell could the speaker not work? I thought maybe I wired the loom incorrectly or the cps2 board wasn't connected to the stereo plug. Tried another PCB and it was the same issue. Insert a couple of profanities at this point because I knew what I needed to do.. take the monitor out again to investigate further FML


With the monitor out, I quickly made an extension wire to commence the trouble shooting




Wired the right channel to the left speaker which wasn't working - she worked!


I then wired up the left channel to the right speaker which I knew 100% worked - didn't work. So it became evident the left channel is the issue.


Grabbed the trusty multi meter and tried to translate the wiring diagram




Continuity was confirmed against all points on the left speaker and connector so it wasn't the wiring. I placed the psu back and to see how it was touching and it didn't "look" right, so I unscrewed the connector and just straightened it a little and then gave the psu a good push to make sure the connection was secure.


Gave it a whirl, and boom!! Both speakers were working perfectly!!



At this point I had a massive sigh of relief that I didn't have to take the whole cab apart :) I was not looking forward to that.


Next on the list is the cp... the cp has been sitting for a couple of weeks now so I figured it's time to put it back together.


The bare cp




A new 100 yen sticker, the cp and the move list DDP art with the glass cover all installed




I had already modified the coin mech to accept the capcom tokens, but I didn't realise the token didn't fit the coin slot!




Easy enough fix with some filing to extend the cut and a number of different tokens will now go through instead of just 100 yen and the smaller namco/taito tokens.




Final testing was to put the 360 and see how it looks, of course the first game to load is Futari! :)




I need to fix the geometry of the monitor, but if I can't fix that immediately, I will park it and look into it at a later point so I can finish the cab.


The end is soooooo close!

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Push through last night and installed the cp and 3 button harness just to get going!


Happy to report everything is working properly!


Here's a quick test run with DDP DOJ on IGS PGM



One issue I have (and a lot of blast city owners) is corner convergence. Not much I can do about it at the moment until I get some convergence scripts, but there's also a massive bow in the geometry.




Look at that woeful geometry!!!


I knew there was an extended menu for the 2931 and I figured I'd give mucking around the settings to see if I can somewhat get rid of the bowing and straighten. To my delight, I was able to get it much better than when I first started.




It's time to look for some blast city decals to "finish" it off!


I must say, as much as I've hated this project and have hated working on the blast, once it's all done and working, she's definitely a nice looking unit! :D Much nicer to look at than the NNC shape (but I much prefer doing maintenance on the NNC than the blast)

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  • 2 weeks later...
  • 2 weeks later...

Into the final stages of this project.


It took a couple of attempts, but I've come to the conclusion when I use a NetDimm on the Blast City PSU, I can't use it on a single PSU. I've been told to do a re-cap on the PSU which "should" fix it, but we will see (cap kit has been ordered).


When I was testing the Naomi using the Sega 001 loom, using a Sega to JVS Jamma IO, every time a game loaded, I would get this error and doesn't show up in the test menu




The moment I use a separate Sun PSU, everything is seen correctly as expected




PSU is reading exactly 5.0v and 3.3v






If I take out the NetDimm and use a normal cart, the IO is seen using the Sega 001 loom. Since the NetDimm is a power hungry unit, I will try the re-cap when I get it, but as an interim, I've installed the Sun PSU with an inline switch I've thrown into the control panel so when I turn the machine on, I can also turn the Naomi on.


Now I've sorted the Naomi out, it's time to finally put them all together. During this point, I was literally humming the gameboy tetris music :D. It took a number of tests, but I eventually got there! Made use of the 5v on CN12 of the Naomi to power the Raspberry Pi






The first pcb is the Sega I/O. I attached it to a fingerboard so I can do a "kick harness" style as this particular I/O normally sees buttons 4, 5 on the Jamma edge and the normal working I have for my harnesses are B1, B2, B3 and then kicks for B4, B5, B6 (not that I need 6 buttons for a shumps cab, but since this cab will also be using a 360, navigation purposes I need an "a and b" which are B4 and B5).


The next pcb is another fingerboard to provide power to the UVC and also use the JAMMA edge to connect to my "PS360 arcade box" which I made a few years back for this exact purpose - using a 360 controller with a jamma edge using Sega wiring schematics.




The wires plug directly to the 12 way connector coming out of the fingerboard and the kick harness goes directly to the kick harness on the cab. The kicks are mapped to (A, B and RT)


Inside that box, there is a spaghetti of wire hidden well :D :D




The 3rd pcb is the unicorn of a pcb that down scales the 480p signal from the 360 to 240p RGB goodness! Why would I downscale 480p when the Blast City takes 31khz? Simple, I want to see those scanlines for the shmups on the 360 :D




This is the closest I can ever get to a CV1K game in 15khz


The price of DDP SDOJ is out of this world and I'm far from skilled enough to be able to tell you the difference between arcade pcb and port, so this method will do :)




With all that said and done, once all placed in the cab, she looks like this!




Only thing left for this cab is for me to order some side decals from Noodleshirt.


Playing games on this unit is quite satisfying and has slowly become a favourite :D

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  • 3 weeks later...

So the feedback I got from a few people was to "recap" the PSU and it "should" fix my issue with the Sega I/O


TL;DR - I'm exactly in the same situation as I was prior to the recap :D


Blast PSU Recap Adventure :D


After getting my cap kits from Arcade Parts and Repair last week, I thought I'd "see" how I go last night with my first attempt at "recapping"


First the disassembly - wow. Didn't realise how filthy this PSU was and I genuinely thought I cleaned this when I cleaned out the first PSU, but obviously didn't *facepalm*


Sorry for the spam of pics, but it's the best way to show how bad it was :)





Found a little friend :)

















Commenced the first lot of caps C36 and C44 listed as 50v 0.47uf.





The only cap I could find in the kit are these





Now I'm not an electronics guru, but I asked a few people and I was recommended NOT to use the tantalum capacitor vs electrolytic found on the PSU. I decided to leave those caps for the time being as I don't really know which way to put them on. The notes on the cap kit is the +ve side is normally the longer leg and the "stripe" side is normally the -ve side but since I wasn't 100% sure, I didn't recap C36 and C44.


Being my first recap and lack of experience, I learnt a quick lesson - don't pull the caps even though you think it's already desoldered!


As a result of the blob that was on the cap securing it, I yanked out the cap but also ripped a trace! FMD! *facepalm*





C39 was the one trace that got ripped off (fortunately, things are still working!)





One of the last things to do was the PSU fan - damn that things was loud! Enter Noctua NF-A8 FLX to save the day! I cannot get over how MUCH of a difference this has made. I had to triple check the fan to see if it was working as I could not hear it at all compared to the stock PSU fan that was there.





3 or so hours later the recapping was complete for both the psu and the sound amp - what an effort! I probably could've blitz through it a lot quicker by taking all the caps out first and then soldering them, but I went one by one so I could be 100% sure the values were correct and the documentation was also correct. Needless to say, it was a painful task.


At this point, I quickly assembled it again to test to see if it turns on (due to that trace) and if it fixes the issue that I did a recap in the first place.


PSU turned on - phew! But the IO still wasn't seen, so I was back at square one albeit recapped and cleaned psu.


PSU is now as clean as I can get it without taking apart most of the components.









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Nice work! Can you provide more details about the pcb that down scales the 480p signal from the 360 to 240p RGB? How does the 360's dashboard and game menus go displaying at 240p? Are you worried about the 360 overheating jammed in the middle there? Cheers, this is an awesome restore for playing those Cave titles.
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Thanks. The pcb is a little unit called universal video converter. Unfortunately, it's a bit of a unicorn pcb, I searched high and low for it and spent a bit of coin to get one.


​​Only place you can find them are the forums, ebay.


Emphatic wrote about it here




There's also a pretty big thread on the shmups forum about them.


The dashboard looks horrible in 240p and there are some games that are a little difficult to navigate through (sdoj comes to mind) but once in game, I can't be happier. Colours are good, I don't feel any major lag and most importantly, there's scanlines! 😅 I'll gladly play futari like this than pay 3k+ for the pcb. I'm perfectly OK with that :)


As for the 360 overheating, I haven't had any major issues just yet but the longest I've played for is about an hour and this is the new and improved 360 corona, so it's not like the original Zephyr, Jasper, Falcon models where heat was a major issue.




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