Blast City Club

grendelrt

Super Spy Agent
Joined
Apr 22, 2014
Posts
623
got mine off YAJ years ago for under 200. gotta have a spare ;)

So this is the question Kuze and I have been batting around. Is it worth testing the chassis when it gets here? My Blast City runs perfect now, so taking out the monitor and switching out the chassis seems like a risk when I currently have no issues, but if I don't then there is no guarantee years from now when I pop that backup in that it works lol.
 

dipindods

needs help. stuck in virgina.
Joined
Apr 23, 2012
Posts
552
ok so one of my blast has had bad speakers since i got it but since its not my main 2 i never took care of the problem. i noticed the right one wouldnt work and left was working but not loud and was very grumbled (if thats a word)
so today i decided to take it apart and replace the speakers with the spares i had. i got 2 new speaker boxes from the group buy and swapped them for ones in my main blasts that werent the best but still worked. so the spares i have do work so i wanted to put them in my 3rd cab today. but when i plugged them in still the right side wont work and the left sounds the same low and grumbled. so now i know its not the speakers what else could it be? and im kinda a noob at the technical talk so dumb it down alot if ur gunna help me hahah :)
tanx guys
 

Westcb

Give an Azn, A Break Here!,
Joined
May 17, 2012
Posts
1,190
ok so one of my blast has had bad speakers since i got it but since its not my main 2 i never took care of the problem. i noticed the right one wouldnt work and left was working but not loud and was very grumbled (if thats a word)
so today i decided to take it apart and replace the speakers with the spares i had. i got 2 new speaker boxes from the group buy and swapped them for ones in my main blasts that werent the best but still worked. so the spares i have do work so i wanted to put them in my 3rd cab today. but when i plugged them in still the right side wont work and the left sounds the same low and grumbled. so now i know its not the speakers what else could it be? and im kinda a noob at the technical talk so dumb it down alot if ur gunna help me hahah :)
tanx guys


Your amp is borked. There is a mono and stereo amp on the sega model 3 amp in the psu, I have two bad amps myself and that is exactly what happens to mine as well. I changed virtually every damn part on mine (all caps, the amp chip, voltage regulator, etc...) damn thing still doesn't work. I have seen one from time to time on eBay but it's about 40 bucks and the description saying it's as is keeps me from buying it. Same amp is also used in the nvs 4000 psu as well. I have working Naomi and sega model 2 amps if anyone wants to trade me a working model 3 :-)
 

cornerstone

King's Dry Cleaner
Joined
Sep 13, 2013
Posts
384
A friend gave me a game elf to try on the blast the other day. The image looks something like this:

photo.JPG

The guy who took that picture adjusted his horizontal freq/hold on whatever monitor he had and it fixed it. I've done this on older american monitors I've had as well.

Does the blast have dial that very subtly adjusts the horizontal frequency? There's probably an easy answer, but I guess I'm more confused with how the manual sync works when I flip the switches to 15khz or 31khz.

Is it possible this multiboard is operating at a weird frequency that the blast won't ever recognize?

EDIT: For what it's worth, an autosync NNC won't recognize the board either. I do have an adapter strapped on it.
 
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Westcb

Give an Azn, A Break Here!,
Joined
May 17, 2012
Posts
1,190
A friend gave me a game elf to try on the blast the other day. The image looks something like this:

View attachment 26677

The guy who took that picture adjusted his horizontal freq/hold on whatever monitor he had and it fixed it. I've done this on older american monitors I've had as well.

Does the blast have dial that very subtly adjusts the horizontal frequency? There's probably an easy answer, but I guess I'm more confused with how the manual sync works when I flip the switches to 15khz or 31khz.

Is it possible this multiboard is operating at a weird frequency that the blast won't ever recognize?

EDIT: For what it's worth, an autosync NNC won't recognize the board either. I do have an adapter strapped on it.


Are you using 15hz or 31hz mode? I have ran into some of those Chinese multi boards that when in 31hz mode the board itself was outputting 800x600 not 640x480 which can cause the screen to get jacked up like that. Just for science here, try switching to 15hz mode and feed the video through the jamma harness. If that resolves it then quit running it on your blast as it can actually mess up your monitor (happened locally to a guy i know on his blast using one of the pandora boards) feeding it unsupported resolutions.
 

dipindods

needs help. stuck in virgina.
Joined
Apr 23, 2012
Posts
552
Your amp is borked. There is a mono and stereo amp on the sega model 3 amp in the psu, I have two bad amps myself and that is exactly what happens to mine as well. I changed virtually every damn part on mine (all caps, the amp chip, voltage regulator, etc...) damn thing still doesn't work. I have seen one from time to time on eBay but it's about 40 bucks and the description saying it's as is keeps me from buying it. Same amp is also used in the nvs 4000 psu as well. I have working Naomi and sega model 2 amps if anyone wants to trade me a working model 3 :-)


ok so where can i get the amp? is it available?
 

cornerstone

King's Dry Cleaner
Joined
Sep 13, 2013
Posts
384
Are you using 15hz or 31hz mode? I have ran into some of those Chinese multi boards that when in 31hz mode the board itself was outputting 800x600 not 640x480 which can cause the screen to get jacked up like that. Just for science here, try switching to 15hz mode and feed the video through the jamma harness. If that resolves it then quit running it on your blast as it can actually mess up your monitor (happened locally to a guy i know on his blast using one of the pandora boards) feeding it unsupported resolutions.


Neither mode works. I've tried different combos of dips on the blast and the VGA/CGA dip on the board itself with and without the VGA plug in. The picture I attached is from the 15khz mode, the other looks slightly different.

Later this weekend I'll try adjusting it on a 15khz only monitor with pots.

But just to be clear, there's no manual frequency adjustment on the blast monitor itself?
 

Westcb

Give an Azn, A Break Here!,
Joined
May 17, 2012
Posts
1,190
Neither mode works. I've tried different combos of dips on the blast and the VGA/CGA dip on the board itself with and without the VGA plug in. The picture I attached is from the 15khz mode, the other looks slightly different.

Later this weekend I'll try adjusting it on a 15khz only monitor with pots.

But just to be clear, there's no manual frequency adjustment on the blast monitor itself?


There seems to be an adjustment for everything on a nanao, but it's more likely your multi board has some kind of sync issue. Cheap components and all... A quick and easy check is hook it up to any computer monitor via the VGA port. If you get a stable image I would gather maybe something needs tweaking on the monitor. Also is there any dip switches that need to be set on the board between the two video modes? Come to think of it i remember the image quality being crap in cga mode on my new Astro but looking decent on VGA mode on my trisync LCD panel. The low Rez mode was tolerable on a WG K7000 though.
tl,dr
Hook it up to a PC monitor and take a pic.
:-)
 

cornerstone

King's Dry Cleaner
Joined
Sep 13, 2013
Posts
384
So I actually hooked it up to an old 15khz cabinet I have and after adjusting the horizontal hold it works. It's a very precise frequency but it works. This also confirms a solution I read about on the internets somewhere.

ImageUploadedByTapatalk1435882805.864343.jpg

The monitor doesn't like the color blue unfortunately, but that's a known problem.

Anywhere to go with the blast from here?
 
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dipindods

needs help. stuck in virgina.
Joined
Apr 23, 2012
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ok so i got the new amp in today and swapped out old one.....and still no sound. and i know the speakers are good i checkd them with my other power supply in it\

what else could it be?
 

Westcb

Give an Azn, A Break Here!,
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May 17, 2012
Posts
1,190
ok so i got the new amp in today and swapped out old one.....and still no sound. and i know the speakers are good i checkd them with my other power supply in it\

what else could it be?

So you have a working psu that when you plug it in sound works completely fine?

For giggles, take the amp out of your known working power supply and put it on the one not working, reassemble, turn on, this way you can truly rule out the amp but honestly there is no other piece it can be if you plug in a whole other psu and sounds works exactly as it should.
 

dipindods

needs help. stuck in virgina.
Joined
Apr 23, 2012
Posts
552
yeah my other psu from my other blast works fine in that cab. ok ill swap out amp in that one to one thats not working
 

Westcb

Give an Azn, A Break Here!,
Joined
May 17, 2012
Posts
1,190
yeah my other psu from my other blast works fine in that cab. ok ill swap out amp in that one to one thats not working


Yeah will just take you about 10 mins to try it and put everything back together. I will be very surprised if you put the new one in your old PSU and it works, but if you try on both and know it works for sure I'll buy it off you if you have no need for it.
 

Chempop

BESTEST Buttrider in chat.Officially No.10 at Schm
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Don’t take this as insult, it’s something someone might stupidly overlook (I have done this several times already)- if the 001 loom is connected on ‘stereo’ instead of ‘line’?
 

Zapperkhan

Kula's Candy
Joined
Oct 2, 2013
Posts
306
Don’t take this as insult, it’s something someone might stupidly overlook (I have done this several times already)- if the 001 loom is connected on ‘stereo’ instead of ‘line’?
I made this mistake a few weeks ago haha.
 

dipindods

needs help. stuck in virgina.
Joined
Apr 23, 2012
Posts
552
Don’t take this as insult, it’s something someone might stupidly overlook (I have done this several times already)- if the 001 loom is connected on ‘stereo’ instead of ‘line’?

haha im never insulted. it has the 001 loom on it. how do i change it to sound from jamma edge?
 

Chempop

BESTEST Buttrider in chat.Officially No.10 at Schm
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i had it slightly mis-worded.
It’s these yellow doodads:
16047817659_ac51aafc06_o.jpg

if using RCA stereo inputs, you want the ‘line', for jamma just 'speaker' iirc.
 

dipindods

needs help. stuck in virgina.
Joined
Apr 23, 2012
Posts
552
nope it wasnt that it was plugged into speaker. ill try swapping amps from good one to bad one maybe the one i bought dont work as well
 

dipindods

needs help. stuck in virgina.
Joined
Apr 23, 2012
Posts
552
so i put psu from working blast into bad one and it works fine. so i took the amp out of the good psu and put it in the one not working. plugged it in and its working. so i took the new amp and put it in the psu from the other cab that works and no bueno. i was sold a non working amp. now i gotta return it and start all over again :(
 

Westcb

Give an Azn, A Break Here!,
Joined
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1,190
so i put psu from working blast into bad one and it works fine. so i took the amp out of the good psu and put it in the one not working. plugged it in and its working. so i took the new amp and put it in the psu from the other cab that works and no bueno. i was sold a non working amp. now i gotta return it and start all over again :(


Yeah bud I knew something was up when you said it didn't fix your problem, good news is you now know for a fact that's what's wrong. Bad news is you now have two bad amps :-( I'm up to 3 myself and wish I knew who to send them to for repair as shot gunning every part on one of mine didn't fix it. Can I ask where you got yours? I wanna make sure I don't buy from the same place. Also hopefully if you did eBay you can try to return if they are a reputable seller.
 
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