Possible screwed ST-V board, or repairable?

[Skyline]

I had been in talks with the folks at the Atlantis Casino's arcade to house my quasi-recently acquired Radiant Silvergun ST-V kit. Well, the game was finally tested on Tuesday, and the results were not that impressive..

First off, the cab it's being connected to is replacing a US-bios Atomiswave board, and is using that cab's power supply. The ST-V board is a JP bios. I should also note that the board was sold to me as a fully functional unit, including the game carts themselves.

On to the suck: while running TEST, the board crashed during the Memory check, showing a bunch of garbage onscreen. We ran it again and it yielded the same results. As for loading the carts themselves, it only loads the games 1/3 of the time, freezing otherwise. When they do decide to load, the games tend to crash whenever there's a lot of screen activity. In RSG's case, this usually happened during the Stage 3-C Boss battle, although it also froze up on Stage 3-B as well, on the diagonal corridor runs. As for Soukyugurentai (my extra cart), the game crashes whenever a bomb is used, and doesn't load past Stage 2.

Since the board arrived at my home, it has been at my home, still in it's box, in it's bubble-wrap encasement. I inspected the board itself shportly after it arrived, and there was no major signs of damage or mishandling (it was literally ENTOMBED in bubblewrap). I transported the board in it's shipped packaging to the arcade, where it was kept until about two days ago, when we got the go-ahead to replace Guilty Gear Isuka. My roomate (and the tech at the Atlantis Casino's arcade, coincidentally), said that there was a bent pin somewhere around the JAMMA connector, that was eventually straightened out.

It might just be a simple case of the board getting somehow damaged during shipping, but it was packed and secured pretty well.

I welcome any input anyone has regarding this issue, including any reccomended maintenance that should be performed, such as cleaning solvents for the carts/cart slot, any specific areas of the board that I should pay careful attention to as far as potential damage is concerned, etc. If anyone has also experienced any of these problems with other boards, I welcome your input as well. And since I'm not at all that knowledgable about what types of power supplies work with what types of games, if the main culprit is the cab's power supply (whether it be a voltage difference or anything else), then please let me know which kind should be used. Thanks in advance.

[footix]

stv carts that don't have dead rams are hella hard to find...
plus these boards are really picky about voltage...

[SAM]

Well, I am sorry I don't know much about ST-V, the costiest thing resemble a ST-V in my house is the Saturn.

Have you try another cart? Or try the RS on another ST-V board?

[system11]

Could be almost anything, I'm afraid.

As suggested, check the voltage first (reading about 5.06 under load is ideal - that means powered up and measuring using the exposed 5v and ground pins), also use an alcohol solution to clean the cart connector, my Souky would fail to boot (claiming no cart) randomly until I did that. Get hold of another STV cart (any game), and another STV motherboard if at all possible, and rule out which bits do and don't work.

If the motherboard is faulty, check solder joins on surface mount chips, sometimes they crack and minute flexing of the board can cause all sorts of strange effects. Past that, it's probably best to get a new one. Without the proper tools you can end up chasing problems like this for a long, long time.

[PC Engine Fan X!]

For Skyline,

As the previous owner of your ST-V mobo with RSG & Souky, I had trouble with the ST-V mobo freezing up on me until I asked around here on the Shmups.com "Hardware" forum. The simple answer was that since I was using a Supergun that was powered by a PC power supply and plugged into a computer surge protector, the ST-V wasn't getting enough juice -- hence it would "freeze" up during gameplay. The simple solution was to directly plug into the A/C outlet and volia, no more freezing up of the ST-V games.

I ran the ST-V's built-in memory check test before sending it out to you...it passed successfully. It confirmed that it was working 100% operational.

As some arcade PCB hobbists here on the forum would say that it's better to use a real arcade power supply rather than a PC power supply for powering up a Supergun setup...I've been told that by using a PC power supply is very clean and stable. But some arcade PCBs (such as the ST-V mobo) are very picky when it comes to voltage conditions...getting too little voltage and one will run into some problems with a ST-V game cartridge freezing up.

My suggestion is to use a voltmeter and check the power on the 5v line when the ST-V mobo is powered up and find out what the voltage reading is. On your arcade cabinet's arcade power supply unit, there should be a 5v adjustment pot -- adjust it so that it delievers just a tad bit more voltage and hopefully, your ST-V mobo will be fuctional again. IIRC, the optimum voltage requirements for an ST-V mobo to function properly would be at (5.06v-5.08v). Just take your time and note at exactly what precise voltage that the ST-V works at without the game freezing up and leave it at that.

I would use compressed air to blow out the dust on the ST-V cart slot and ST-V game cart pinout PCBs to make sure that the ST-V game carts were as clean as possible when powered up on the ST-V mobo.

I would use the "Select" button to highlight the ST-V game that is being read by the ST-V mobo and start it up to listen to the BGM tunes...if the BGM tunes play fine, then the ST-V mobo is fine operational-wise. I'd exit out the respective ST-V game's menu and go back to the main ST-V mobo's screen and finally boot up the ST-V (and skip the memory test entirely) and the game would load up without any problems.

When an ST-V mobo is up and running properly, with RSG ST-V cart using a JPN Bios setup, it is pure shmup heaven with a 3-button setup.

PC Engine Fan X! ^_~

[SAM]

As some arcade PCB hobbists here on the forum would say that it's better to use a real arcade power supply rather than a PC power supply for powering up a Supergun setup...I've been told that by using a PC power supply is very clean and stable. But some arcade PCBs (such as the ST-V mobo) are very picky when it comes to voltage conditions...

Second that, we should really use a real arcade power supply because...
(1) You got the -5V line, some older board really need this.
(2) You could adjust the output voltage, some PCBs actually require 4.7V and stop working at 5V.

And about the point PC's PSU could not provide enough current?!?! Actually I really doult this. Since a modern PC consume a lots of power. It got fans, harddisks & CD-ROMs, it actually consume much more power than a PCB, so why a PC's PSU would not able to provide enough power to an age old PCB?

[oxtsu]

I've been told that by using a PC power supply is very clean and stable.

Arcade PSUs are as well, when set up properly. :) They just need a line conditioner/filter before the PSU's AC input. Any good cabinet will have one wired up. PC style power supplies, on the other hand, usually have the line conditioner built in.

And about the point PC's PSU could not provide enough current?!?! :? Actually I really doult this. :o

It's true. The typical PC style PSU used in a supergun has 3 to 5 Amps on +5V. That's not enough for some some JAMMA PCBs. Also, it could be related to their self regulating voltage.

[SAM]

And about the point PC's PSU could not provide enough current?!?! Actually I really doult this.

It's true. The typical PC style PSU used in a supergun has 3 to 5 Amps on +5V. That's not enough for some some JAMMA PCBs. Also, it could be related to their self regulating voltage.

Oh you guys are using the PC's PSU come with the Supergun, no wonders.

Most of my friends over here are using the PSUs removed from their old PCs.

I personally think those PSUs are so powerful that they easily turns into PCB cookers.

[system11]

I'll just add here - there's a reason that so few arcade machines have self regulating power supplies, and why repair documents exist for those machines.

PC supplies aren't even much cheaper than a proper one either - unless you go for the ultra-ghetto ones. PCBs are expensive. Treat them as such.

[dpful]

From my experience with STV---
Clean the cart by plugging/unplugging it repeatedly.
Turn up the 5v. The result of a low 5v is freezing for STVs, so any power supply with an adjustable 5v should be OK.

[PC Engine Fan X!]

For Skyline,

So there you have it, dpful has simply stated that a low 5v output will cause an ST-V mobo to "freeze" up. So just a little cranking up on an adjustable 5v line on an arcade "power supply unit" should clear up any ST-V mobo freeze-up issues -- and you're good to go. ^_~

For Bloodflowers,

Matt has stated on his custom-made Superguns, the reason why he used PC power supply because it is very stable & reliable -- even has a built-in cooling fan to cool the insides of his professional built Superguns like mine. ^_~

PC Engine Fan X! ^_~

[system11]

For Bloodflowers,

Matt has stated on his custom-made Superguns, the reason why he used PC power supply because it is very stable & reliable -- even has a built-in cooling fan to cool the insides of his professional built Superguns like mine. ^_~

With respects to Matt who apparently makes a fairly decent unit, he's wrong.

You're talking to someone who has collected and repaired more cabs than probably the rest of the regular forum users put together (I know a couple of lurkers though with massive collections) I used to repair PCBs and cabs to finance the hobby.

1) Most PC power supplies do not give you a +5 adjust. This is absolutely critical for arcade playing. Did you know 5.1v will fry a Nemesis (Gradius) quite easily?

2) Arcade power supplies generally don't need a fan. No moving parts, quieter, you can leave it running and it'll never cook the inside of your supergun, and a reduction in possible interference.

3) Because most don't try to self regulate, with an arcade PSU there's less danger of oversupply and resulting damage. There used to be a few models (for example the Hantarex ones found in European Chase HQ cabs), but operators used to replace them wherever possible for just this reason. Try using a PCB with dirty contacts and see how nicely cooked it can get Also see below.

4) PC supplies now output quite a bit more power than an arcade one. If the board develops a fault (note that shorts and similar don't always cause PC or arcade PSUs to trip), you've got an awful lot more power to break things with before something actually does trip (or simply go bang).

[D]

Most PC power supplies do not give you a +5 adjust. This is absolutely critical for arcade playing. Did you know 5.1v will fry a Nemesis (Gradius) quite easily?

Could you please help us save pcb's by tellingus ofpotential hazzards like the one described.
Which pcb's should be treated with care Voltage wise?

[system11]

Most PC power supplies do not give you a +5 adjust. This is absolutely critical for arcade playing. Did you know 5.1v will fry a Nemesis (Gradius) quite easily?

Could you please help us save pcb's by tellingus ofpotential hazzards like the one described.
Which pcb's should be treated with care Voltage wise?

"All of them"

Seriously though, some games just seem more vulnerable than others. IN MY OPINION older Konami ones on Nemesis hardware are particularly bad, and older (although actually up as far as System 1) Namco stuff is loaded with pretty intolerant custom chips. If you have something with any kind of reputation for unreliability - just don't abuse it in any way, including over voltage.

Strangely Capcom (except PSX based hardware) boards seem nearly indestructable. I had a 1943 once that someone had used in a cab with a self regulating Hantarex (well, it had no labels, but the description matched). The 5v pins topside were actually burned to a crisp, PCB material itself blackened underneath. Still worked after I made new edge pins for it (you can get adhesive strip metal for this).

[dpful]

Don't want to hijack the thread, but I just got a lifeforce PCB in the mail today and it won't boot up- just a frozen garbled boot screen (a little different every time, no less), and a ticking coming from the speakers.
It may have been getting about 5.1v from an arcade-style power supply.
Any advice? Do those symptoms soud familiar?

[thchardcore]

Fuck, if i have a SPI, cps1 and some raizing (garegga) stuff should I switch from a SC200 to a real Arcade psu to be safe?

[system11]

Ok, I wasn't trying to cause mass hysteria.

If you have a PSU which under load feeds an average single layer board around the 5.06v mark, it's probably going to be fine. It's just with PC supplies the potential for damage is greater /if/ something does go wrong, and you never have the option of adjusting for games that glitch with the wrong amount or draw a lot of power (Raiden for example gets sprite flicker sometimes). It's definitely something to consider when buying a supergun or cab, if you have a large number of /very/ expensive games, or very old ones. Personally I would switch it, but that's just me.

As for your Lifeforce dpful - yeah, that's very familiar. That board is actually a newer JAMMA revision of the hardware used by Nemesis, and suffers some of the same problems (mostly the input chips fry). Check your voltage, try again, then resocket all socketed chips and try again (except for those horrible ones that look like centipedes). Next you'll need to get the rom chips verified as good. While it could be bad RAM or customs causing the screen garble, it could just as easily be bad ROMs crashing it. The ticking noise is likely the sound CPU resetting endlessly. Ignore it until you can at least get test mode to appear.

[Skyline]

Hey, just thought I'd make an update.

After days and days of procrastination on the arcade's part (well...that and they kinda got new games), RSG was loaded up again, taking the advice offered from, PC-Engine fan X!, dpful, and anyone else that had any input on the matter.

Yep, the board's still FUBAR.

The weird part is, now it works less than it did before. RSG and Souky both don't load past their respective company logos, Souky in particular doesn't even display the "ING" in RAIZING. The highest amount of juice the ST-V was fed was 5.08, and still nothing.

Memory/system tests turn up okay (doesn't freeze during the final memroy test anymore, weird), and the carts do load, but anything further than that crashes the system.

It's looking more and more like the thing was damaged during shipping...still, the whole voltage issue perplexes me to no end.

EDIT: Just got the exact numbers from the tech there, the initial test was at a little less than 5.00v, not the 5.6v I originally thought.

[oxtsu]

It's not just voltage, but also current (Amps). How many Amps on +5V does the power supply in this cabinet put out?

[mortified_penguin]

I really hate to bump such an old topic but I'm having the same exact issue.

Just bought a RSG cart and a Bios modded STV board and it's locking up. If you remove the cart the board boots up and does it's little demo loop just fine. Plug the cart back in and it either doesn't boot up at all or freezes, usually around boss fights. When it comes to the voltage I keep getting 4.6 volts under load no matter how much I adjust the PSU. I've cleaned the contacts, there's no surge protector or anything involved, and as stated I tried cranking up the voltage.

Any ideas? I'm barely squeaking by here after purchasing both and this issue is just salt in the wound.

[PC Engine Fan X!]

I had to resort to buying a 2nd JPN region ST-V mobo...it works like a charm despite both cart tabs broken off. If you have access to another ST-V mobo, try the RSG ST-V cart on a second one and see if it works or not.

PC Engine Fan X! ^_~

[mortified_penguin]

Unfortunately I only have the one board to work with. After further testing it seems the JP bios doesn't lock up, (which is a shame, I actually kinda liked the simplified US version), but the sound goes nuts around stage 2B. Gaaaah, it's always something.

[system11]

Clean the contacts on the cart with an alcohol solution and a cotton bud. Next, do the same thing on the edge connector.

[pcb_revival]

Try the extended testing sequence.

Quoting channelmaniac from NG.com

Hold down the test button while powering it up to access the factory tests. Run the test on the slave CPU and if it fails.


The ST-V main pcb must be one of the most fragile/tempremental arcade systems ever to be manufactured.

SEGA R&D dropped the ball.

[mortified_penguin]

Ran the test sequence and both the cart and board checked out fine with the exception of RS-232C and SCSI2, not even sure what that means.

http://i189.photobucket.com/albums/z296 ... V/STV4.jpg
http://i189.photobucket.com/albums/z296 ... V/STV5.jpg

I'm wondering if it's as simple as my PSU just isn't putting out enough juice. I've run into that before with some older boards. Another odd detail is that I have a lot more trouble getting the board powered on at night than I do during the day. Weird.

[dpful]

If your adjusting the psu and the voltage reads the same, it's got to be a broken psu. Besides that, asyou turn the voltage down on those, they freeze. So that's got to be it. Dirty contacts could also cause q freeze on a jiggle, but I bet you just need more voltage

[system11]

If your adjusting the psu and the voltage reads the same, it's got to be a broken psu. Besides that, asyou turn the voltage down on those, they freeze. So that's got to be it. Dirty contacts could also cause q freeze on a jiggle, but I bet you just need more voltage

Dirty contacts can also cause the "I'm turning +5 up but nothing is happening" issue too - you'd also feel the edge connector warm up slowly. Usually when they're that bad you can tell though, there will be a sort of cloudy white corrosion on the pins.

[channelmaniac]

Nice to see my posts & repair logs come in handy!

The STV is an odd duck that is very easy to damage by flexing the board.

Try a few things to see what happens:

1. Fold over some white posterboard a couple of times until it's as thick as a cart board. Put alcohol on it and repeatedly insert/remove it from the cart slot. See if you get some nasty crud out of the socket.

2. Clean the JAMMA connector with a pink pencil eraser. Scrub it until it's nice and shiny. DO NOT use "ScotchBrite" pads or anything more abrasive than the pencil eraser.

3. Adjust the power supply to 5.05 to 5.1v AT THE BOARD, not at the power supply. There will be some losses in the wiring.

4. Clean the cart's edge connector with the pencil eraser. You'll need to disassemble the cart to do this.

If that's not it AND if the Slave CPU test passes then grip the main CPU and board between your finger & thumb and squeeze on it while booting and trying the game. If it doesn't freeze up then reflow the CPU.

Any ST-V system that crosses my bench gets the main and slave CPUs reflowed. They are a common problem point. Any system that is randomly locking up should have that done before condemning the board as junk.

Oh, and as for boards that get damaged by high voltage... Sega NAOMI carts die if you run them at 5.2 or above. Those tiny 16 bit buffer chips can't handle it.

Raymond Jett
arcadecomponents.com

[Ex-Cyber]

Because most don't try to self regulate, with an arcade PSU there's less danger of oversupply and resulting damage.

Can you explain what you mean by this? That is, do you mean that it's essentially a transformer+rectifier+rheostat or similar without even a linear regulator, or what?

[channelmaniac]

Ran the test sequence and both the cart and board checked out fine with the exception of RS-232C and SCSI2, not even sure what that means.

http://i189.photobucket.com/albums/z296 ... V/STV4.jpg
http://i189.photobucket.com/albums/z296 ... V/STV5.jpg

I'm wondering if it's as simple as my PSU just isn't putting out enough juice. I've run into that before with some older boards. Another odd detail is that I have a lot more trouble getting the board powered on at night than I do during the day. Weird.

Those tests are for options. If you don't have 'em they will fail.