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Dreamstate

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Really a fun read. Nice job so far. I wanted to mention that you may be able to find foam replacement for those old speakers. I was about to throw out some old (but well made) Boston Accoustics rear speakers that I use for 25 years with my home theater. Found that you can often order replacement foam, and it is really easy to replace. Just an FYI if you did not already know or if someone else was unaware.
 

mR_CaESaR

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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.

cxykfIZl.jpg


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!

qmnCeVnl.jpg


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

P8MkMMkl.jpg


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)

pOZPGrkl.jpg


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

tCoe68el.jpg


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!

EcjCoU3l.jpg


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

Z4qAGQEl.jpg


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

3bIEBXol.jpg


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!!

View: https://www.youtube.com/watch?v=J7pfhLlOJ70


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

cwPWfWil.jpg


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

4nfHpJal.jpg


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!

ud3PwFbl.jpg


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.

d8704Q7l.jpg


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

CXLIZGBl.jpg


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!
 

mR_CaESaR

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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.

1NpiAyYl.jpg


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.

9pVOshul.jpg


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)
 

Hedonism Bot 2.0

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That geometry bow is common, I've had it on a 2930 and a 2931. Just how these semi curved tubes are, some are like that from factory.

Looks great though!
 

mR_CaESaR

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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

tQ1KRyKl.jpg


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

YKvH3rrl.jpg


PSU is reading exactly 5.0v and 3.3v

eORGmOql.jpg


eqItNEDl.jpg


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

S76BY98l.jpg


0FxsqbGl.jpg


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.

i6IcDUUl.jpg


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

B7UpGjil.jpg


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

7bT2chzl.jpg


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 :)

nIitqg9l.jpg


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

8GGL7pql.jpg


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
 

mR_CaESaR

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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 :)

tspuZsEl.jpg


Found a little friend :)

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

Xp9YI2il.jpg


The only cap I could find in the kit are these

xxVle7pl.jpg


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*

7qAIfmGl.jpg


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

O7mKc0ol.jpg


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.

QkK3qdql.jpg


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.

Kka8sfil.jpg


6C55yaLl.jpg


p8RtVqKl.jpg
 

THCsoftcore

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What a labor of love. Amazing transformation.
 

DMRSX

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Great thread.

N00b question here: With the Noctua fan swap... do you just connect the red and black wire and not the yellow?
 

mR_CaESaR

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Great thread.

N00b question here: With the Noctua fan swap... do you just connect the red and black wire and not the yellow?

Yes, that's correct. I simply cut the yellow cable. Recrimped with JST XH pins (sxh-001t-p0.6), used the existing connector, I didn't have any spare XH 2 way (only 6 way)
 

mR_CaESaR

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The universe just doesn't want me to love the blast city! :D

Backstory:

The blast city had some "buzzing" that got louder as time went on. After reading a thread on here, it pointed to some stuff inside the yoke and would need "cleaning" but to do so would mean removing the yoke - something I was absolutely petrified of doing due to the risk of damaging the neck.

Last week, I received convergence strips and finally worked up the courage do the maintenance.

Upon removal of the yoke, a few crusty bits came off and some permalloy strips also came off the tube

HY4856ll.jpg


I gave the yoke a good dust with a dry brush and got it to a reasonable state

qHKTYg5l.jpg



After putting back everything, the buzz was mostly gone - still a little buzz, but nowhere near as loud.

I started mucking around with the convergence strips and you can see the difference.

Before convergence strips


After


Only problem I have now is I seem to have introduced "wavy" corners and I have no idea how or why they've been introduced.

I don't believe it can be "caps" as I don't recall this previously and this chassis has been serviced back in October with very minimal use. They seem more prominent on the right side versus the left side, but it's definitely there.

Would loose windings cause this?

If you look at the top there's probably a couple of loose copper.

dotwhzyl.jpg


 

mR_CaESaR

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A lot of trial and error on the weekend :D but still haven't gotten to the bottom of it unfortunately :(

I tried plugging in the vga (31khz) to my naomi universal and I didn't get any wavy corners. Monitor is powered via the blast city, everything else is on the naomi


So I thought, I'd try it on my Blast in 31khz - same result, no wavy corners.

Tried it on my Astro City in 15khz with a new 15 te amp up cable and totally separate from the blast city (didn't use the blast city at all) and unfortunately the wavy corners are still there even when using the astro city


Confirmed that the wavy corners aren't there when using the MS8 on the astro city, so it's definitely related to the monitor and the gut feeling is something in the yoke.

I took out the yoke again for further inspection and couldn't really see anything outside of some residue from the tape

eMqOhIgl.jpg


28YPxMVl.jpg


Upon putting the yoke back, I introduced MORE buzz


I also reached out to Jomac who stated this:

That appears to be caused by some sort of coil vibration, probably not something you hear though. It would be causes by loose coils windings or convergence strips vibrating against the coils, I would find something plastic you can get between the yoke and tube and see if putting pressure on different spots stops it happening, when you find it try putting some silicon on that part to absorb vibration.

After taking out the yoke again, inspecting it some more, this fell out and I thought bingo! This vibrating is what's causing the buzz and interference on the corners.

19UzHVVl.jpg


Unfortunately, upon installing back it got rid of the buzz, but wavy corners are still there.

Going back to what Joey said, I thought those couple of windings that appear to be loose could be the cause, so I tried securing it with electrical tape to see if it had any effect

VZlFwuwl.jpg


Unfortunately no effect :(

So right now, there's still a slight buzz and the wavy corners still exist.

I'm really out of ideas exactly trying to "secure/seal" the yoke as best as I can with silicone as outlined here - http://www.albyhus2.se/_eget/monitors/MS-2930-S/

One side of the yoke has "movement" when you press down on it unlike the outer side that has no movement

 

mR_CaESaR

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Purchased a can of PCB Lacquer to tighten the windings up and used up almost 1/2 the can - she was pretty secured!

eqFKrV2l.jpg


After the initial test, there was no change to the wobble, so the last ditch effort was to impregnate the yoke with silicone.

rA2jfHsl.jpg


There was no way this the windings were vibrating!

Still no difference. I decided to live with it as it wasn't present on 31khz and in 15khz it wasn't all that bad once playing a game. I was fixing the corners and then for whatever reason, I decided to do one more removal of the yoke and when I installed it back, I forgot to plug the yoke connectors to the chassis. I turned it on, heard some buzzing and no pictured. Quickly turned it off and then I realised the yoke wasn't connected. After connecting the yoke back, turned it on, I got this :(

8ptZpODl.jpg


BOOOO!!!!;(;(;(

What do you do, it is what it is unfortunately. Hopefully I can get this fixed.
 
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Offsider

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The dreaded blast yoke buzz!

Quite a daunting task with yoke removal mate , not everyone can do this level of troubleshooting in the hobby. Put it down to another skill added to your repertoire. We are only human after all just a little setback here. Give yourself a pat on the back , I have a feeling she’ll be back up and running better than ever!

-Tom
 
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mR_CaESaR

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Joey's analysis of my 2931

Well turns out mate that it's the tripler inside the flyback that has failed, it had damaged an SMD IC in the regulation section plus the 5 pin regulator and zener protection diode, H-Drive transistors and vertical IC, this is supposed to shut the chassis down but as the IC was shorted it kept driving.
I replaced the blown bits and within a few seconds it blew everything again, so I took your flyback out and put it in another old one of these chassis that's in real bad shape I only use for testing flybacks, anyway within seconds it shutdown like it was supposed to.

I don't have a good flyback spare and the after market ones just aren't any good, also the SMD IC that blew on yours isn't readily available I only found them parts on an old parts chassis, so many hours later ( over 5 today ) still no working chassis !! damn frustrating these things, every time I work on one it only cements why I don't do the MS293xx series anymore.

I do have a nice fully working spare that I wasn't planning on parting with if you want to go that way.

So essentially I FUBAR'd my 2931 - note to self, never turn on a chassis ever again without the H/V connectors from the yoke connected.

I received the working spare chassis on Thursday and to say I was careful when putting on the chassis is an understatement! :D :D

Turned her on... and BEAUTY! SHE WORKS!!! :D :D

After the excitement of seeing it alive again, reality came back down when I couldn't stretch the image wide enough

QxS3ue2l.jpg


See how I was on HSIZE MAX but I'm still missing a big chunk on the right and a little on the left?

On a good note, the video clearly shows that the wavy corners are no longer present. So it must've been the chassis all along and not the yoke!


I guess as a bonus, I have an impregnated yoke. There's still some buzz that occurs when you start up the cab, but seems to disappear after a while.

So after searching for information all over the place, I couldn't for the life of me figure out why I couldn't get the image to expand. I tried the H-Drive pot (didn't change it too much). I tried the "extension" menu with additional settings (hold down a button for 3 seconds) but there was no setting. I know on the 2930 there was a pot HSL for horizontal size limit, but I couldn't find anything for this chassis.

When in doubt, what do you do? RTFM :D :D. I found the service manual of the 2931 - low and behold there's commentary there talking about entering a "factory adjustment mode" which is different to the "extension" mode

rv5cRi9h.jpg


So I did exactly as the manual said to, hold down all three buttons for 3 seconds and VOILA! Factory Mode

4s7ZTFYl.jpg


Scrolled through the menus and what do you know, I came across a H-LIMIT option :D (I went from 18 max to 34).

wnn21Hjl.jpg


What did increasing it from 18 to 34 do? Edge to edge image!

zTEWATOl.jpg


Spent another hour or so trying to get the colour right and this was as good as I could get it

e5AULqFl.jpg


And of course, it wouldn't be my cab without this game on the test bed :D

BeoDRttl.jpg


ngIpqebl.jpg


This was a very good weekend for the cab - unlike a few weeks ago :D

Next to do is fix the corners properly and then do this exercise all again for "31khz".
 

mR_CaESaR

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Spent some time on the public holiday to configure the monitor.

Here's the cross stitch of the monitor before any convergence work..

PNgyQXIl.jpg


After about two hours worth of mucking around and me $h**ting myself, this was the best I could do (also ran out of convergence strips)

ITSNZncl.jpg


The bottom left could probably use another one or two strip, but there's definitely a difference on all corners, especially the top left! In game, it's a lot more forgivable and nowhere near as noticeable as it used to be.

Of course, the back view :) - yep, I got happy with silicone. I really don't want to be taking this monitor out anytime soon

UdlIYTTl.jpg


She's finally back in the cab and I had a good gaming session on Wednesday night.

Was about to drop a few coins on it yesterday until this happened.....

Turned the cab on, noticed something was off when I saw the monitor and upon checking the colour chart... blue channel is missing!! FMD it just doesn't stop! This cab really hates me! hahah

eqoWIrsl.jpg


At this point in time, given the history of this cab, I almost rage quit and threw in the towel, but I stepped away for 10 mins, regathered as I knew I had a spare neck board for this chassis - I already came across this issue with the other blast city and I replaced the neck board.

Back on the "workbench" (aka floor :D), I desoldered the two wires on the neck board and swapped them around. Turned it on and voila! I got blue but no red! ARRRGGGHHHHH

3PS3XCWl.jpg


My last resort before emailing Joey was to reflow the 3 transistors responsible for the 3 rgb channels on the neck board.

Turned the cab back on with the reflowed neck board and bob's your uncle! Everything is back to normal! Thank f**k for that!

U9WcTeOl.jpg


Got her installed again (back didn't like it) and dumped a few credits on DOJ!

uBvUtx0l.jpg


For now, arcade universe is balanced again and I really hope there's no more challenges for this blast city ever. I've been told by a few people to sell it off, but given the amount of work I've put in, it'll most likely be sticking around for a few years :D
 
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