Picked up a Firepower, but have a general fuse question

Bullwinkle

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Picked up a Firepower, but have a general fuse question

I just picked up a Firepower that is in very nice shape, only problem.. no displays, so now begins the troubleshooting. I have the links for system 3-7 repair so I'm following that. Ran into my first roadblock and I want to make sure of what I'm doing prior to moving on.

Figured I'd check the fuses on the power supply board first. The guide says the fuses should be one thing and what's installed is another. Here's what I have:

Fuse: guide / actual installed

F1: 90v AC - 1/4a slo-blo / 250v AGC 1a
F2: 28v DC - 2.5a slo-blo / 250v 3a slo-blo
F3: 18v DC - 8a fast blo / 250v AGC 3a
F4: 28v DC - 10a slo-blo / SFE 20
F5: 5v DC - 4a fast-blo / SFE 20

It looks like the previous owner just put what he had where he wanted it...or he knows more about fuses than I do and these cross reference to the original specs (which I'm doubting).

Now..I have fuses that match the guide, but I just wanted to know if a 3a fuse is a 3a fuse regardless of voltage (ie: AC vs DC) I'm getting confused looking at my fuse packages that state AC voltage on them.

Thanks ...any guidance is appreciated.

-tom
 
I just picked up a Firepower that is in very nice shape, only problem.. no displays, so now begins the troubleshooting. I have the links for system 3-7 repair so I'm following that. Ran into my first roadblock and I want to make sure of what I'm doing prior to moving on.

Figured I'd check the fuses on the power supply board first. The guide says the fuses should be one thing and what's installed is another. Here's what I have:

Fuse: guide / actual installed

F1: 90v AC - 1/4a slo-blo / 250v AGC 1a
F2: 28v DC - 2.5a slo-blo / 250v 3a slo-blo
F3: 18v DC - 8a fast blo / 250v AGC 3a
F4: 28v DC - 10a slo-blo / SFE 20
F5: 5v DC - 4a fast-blo / SFE 20

It looks like the previous owner just put what he had where he wanted it...or he knows more about fuses than I do and these cross reference to the original specs (which I'm doubting).

Now..I have fuses that match the guide, but I just wanted to know if a 3a fuse is a 3a fuse regardless of voltage (ie: AC vs DC). I'm getting confused looking at my fuse packages that state AC voltage on them.

Thanks ...any guidance is appreciated.

-tom

The 250v ratings are fine. As long as the voltage rating is higher than the actual circuit voltage, you're fine. It's the amperage that's critical. Also make sure the slo/fast ratings are correct too. The guide numbers you have there are fine, you can trust them.

That 1A in the 90v circuit concerns me, as that's the display power supply. Makes me worried you might have something blown out in the main display. Definitely get them all back to the correct sizes, some of them are pretty out of whack.

-Hans
 
I just picked up a Firepower that is in very nice shape, only problem.. no displays, so now begins the troubleshooting. I have the links for system 3-7 repair so I'm following that. Ran into my first roadblock and I want to make sure of what I'm doing prior to moving on.

Figured I'd check the fuses on the power supply board first. The guide says the fuses should be one thing and what's installed is another. Here's what I have:

Fuse: guide / actual installed

F1: 90v AC - 1/4a slo-blo / 250v AGC 1a
F2: 28v DC - 2.5a slo-blo / 250v 3a slo-blo
F3: 18v DC - 8a fast blo / 250v AGC 3a
F4: 28v DC - 10a slo-blo / SFE 20
F5: 5v DC - 4a fast-blo / SFE 20

It looks like the previous owner just put what he had where he wanted it...or he knows more about fuses than I do and these cross reference to the original specs (which I'm doubting).

Now..I have fuses that match the guide, but I just wanted to know if a 3a fuse is a 3a fuse regardless of voltage (ie: AC vs DC) I'm getting confused looking at my fuse packages that state AC voltage on them.

Thanks ...any guidance is appreciated.

-tom

As long as the voltage rating is >= the spec you should be ok. The slow blow vs regular (fast blow) is important. Slow blow fuses are used where there can be short bursts of high current (solenoids).

cheers
/Tim
 
The 250v ratings are fine. As long as the voltage rating is higher than the actual circuit voltage, you're fine. It's the amperage that's critical. Also make sure the slo/fast ratings are correct too. The guide numbers you have there are fine, you can trust them.

That 1A in the 90v circuit concerns me, as that's the display power supply. Makes me worried you might have something blown out in the main display. Definitely get them all back to the correct sizes, some of them are pretty out of whack.

-Hans

Yeah..guess what.. no displays...lights strobe when powered up..but no display... well..I've got all fuses where they should be, I have to replace a diode on a coil then I'll start with voltage from the ps.

thanks guys.
 
Which master display board do you have? Does it have a few chips on it? Or a metric-buttload of transistors?


I'd recommend though just running one thread for the machine. You'd be surprised how many problems are inter-related, and it does help to diagnose if I can read back the whole story on the machine :)

-Hans
 
Which master display board do you have? Does it have a few chips on it? Or a metric-buttload of transistors?


I'd recommend though just running one thread for the machine. You'd be surprised how many problems are inter-related, and it does help to diagnose if I can read back the whole story on the machine :)

-Hans

I believe I have the master with the metric-buttload of transistors (see below).. my Flash pin has a much simpler master display which, I believe, once I get my power correct, I can use it to test if the current master is toast.

metric_buttload.jpg

I'll make sure I keep everything in this thread. Thanks
 
Ahhhh, the Firepower has the good style master display. The other one may be simpler, but the transistor version actually is easier to diagnose and repair. The UDN7180 chip is the big bugaboo with the IC style display...... expensive when you can find it.

The two boards can be swapped back and forth no problem, they are totally compatible with each other.

-Hans
 
Well..ran into a locked coil this morning on the right slingshot bumper. This is the coil diode I mentioned a few posts back. Replaced the diode but she's still locked on. Odd thing is, that it was working prior. It would go through the self test and kick it, but I did notice in the self test that when it passed it, it would stick on for a few extra seconds and then release.. Now it doesnt release at all. checking the repair guide to see where to go.

Also, the guide mentions that starting with Firepower, there should be a red & white ground coming from the playfield that should be connected to the headboard ground under the wingnut. I dont see this. I do see a common red & white going from component to component on the playfield, but it doesn't break from the harness for me to connect to the ground bolt/wingnut. Is this normal?

UPDATE:

Checked voltages on the PS board. Looks like the high voltage area will need some new components (I had to do this with my Flash too...but the upside is, it looks like this may be why my display is dead). Here's what I have for voltages:

Connector : expected voltage : Pin(s) / Ground Pin = Actual reading

High Voltage
J6 : +12vdc : 6 / 15 = +13.428vdc
J6 : +5vdc : 7 to 10 / 15 = +5.073vdc
J5 : -90 to -105vdc : 3 / 1 = 0vdc
J5 : +90 to +105vdc : 4 / 1 = +124.82vdc
J5 : +5vdc : 6 / 1 = +5.04vdc

Lamp
J4 : +16 to +20vdc : 5 to 8 / 1 = +20.27vdc

Solenoid
J3 : +28 to +38vdc : 6 to 9 / 1 = +39.40vdc

The lamp and solenoid voltages are just a hair out of range, is this OK?

Also, per the guide's instruction, I replaced the filter cap (originally 12,000uf 16v) with a 15,000uf 25v. The guide says anything between 10,000 and 18,000uf should work fine...and I had that one sitting here.

EDIT #2
I took the master display and put it in my Flash and it works perfectly... so that's good news. I may (out of sheer boredom) take the power supply board from my Flash and put it in tonight to see if she powers up.
 
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Looking at the power supply boards in both machines, they are identical except for what look like two capacitors on the Flash board just below the high voltage area. Is this something specific to Flash that will have adverse effects on Firepower? (see below)

flash-firepower-ps3.jpg

... and I'm no expert, but I'd assume this transistor on the driver board is an issue...

transistor.jpg

That being said, this transistor is at location Q23. Someone replaced it with a TIP-122 (schematic says TIP-120). I'm assuming that a TIP-122 is a suitable replacement. Can someone confirm this?

thanks,

-tom
 
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That missing -100v is your display problem likely, that's the power for the plasma glasses. I'd just snag a high-voltage rebuild kit from GPE and be done with it, replace the whole high voltage section. The 125v showing on there is going to shorten the lifespan of your displays.

TIP122's are an ok replacement, but the preferred one to use is a TIP102 (more robust).

-Hans
 
That missing -100v is your display problem likely, that's the power for the plasma glasses. I'd just snag a high-voltage rebuild kit from GPE and be done with it, replace the whole high voltage section. The 125v showing on there is going to shorten the lifespan of your displays.

TIP122's are an ok replacement, but the preferred one to use is a TIP102 (more robust).

-Hans

Wow...I just checked GPE and their rebuild kit is only $4.50? damn! I'm on it! Thanks Hans
 
Wow...I just checked GPE and their rebuild kit is only $4.50? damn! I'm on it! Thanks Hans

Yeah, I do that kit in all my power supplies. It also drops the +-100v to +-90v, which works find but is just a hair dimmer in the displays. This supposedly extends the display lifespan by quite a lot.

When you do it, I'd try doing everything in the kit except the two transistors first, they are pretty tricky to install because the originals are no longer available and you have to "leg switch" to get the current manufacture stuff to work. If it still doesn't work, then do the two transistors. don't forget new connectors too.

Those extra capacitors in Flash, those really don't matter if they are in there or not. Very early system 3 games also had a +300VDC circuit in the displays, which those are part of, but it was found that the 300V wasn't needed and they stopped installing the parts around the end of the System 4 production run.

-Hans
 
Yeah, I do that kit in all my power supplies. It also drops the +-100v to +-90v, which works find but is just a hair dimmer in the displays. This supposedly extends the display lifespan by quite a lot.

When you do it, I'd try doing everything in the kit except the two transistors first, they are pretty tricky to install because the originals are no longer available and you have to "leg switch" to get the current manufacture stuff to work. If it still doesn't work, then do the two transistors. don't forget new connectors too.

Those extra capacitors in Flash, those really don't matter if they are in there or not. Very early system 3 games also had a +300VDC circuit in the displays, which those are part of, but it was found that the 300V wasn't needed and they stopped installing the parts around the end of the System 4 production run.

-Hans

Well... my local distributor actually has 5 or 6 of each of the original transistors (NTE171 & NTE296) which doesn't surprise me. The originals and the replacements have somewhat different specs..

NTE171=
VCEO - 300V

NTE55 =
VCEO - 150V

as well as other differences. My question is, am I better off with the original transistors or are the newer replacement values a better fit and match the other replacement parts better? Not having to twist the legs of the transistors would be nice. If the replacements are a better fit, I have crossed the legs before for my Flash, it wasn't really that bad..just a bit more time consuming.

thanks,

-tom
 
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If the prices are good, go with the originals. The cross-legged replacements work just fine, but I still think it's a kludgy fix and ugly.

Oh, and don't forget the capacitors too. Even if he doesn't have the whole cap kit, at least get the two 100uf 160v axials that are in the 100v circuit. Those aren't part of the HV kit, they're part of the capacitor kit.

-Hans
 
If the prices are good, go with the originals. The cross-legged replacements work just fine, but I still think it's a kludgy fix and ugly.

Oh, and don't forget the capacitors too. Even if he doesn't have the whole cap kit, at least get the two 100uf 160v axials that are in the 100v circuit. Those aren't part of the HV kit, they're part of the capacitor kit.

-Hans

Cool, I grabbed them.... and I picked up those caps and the other axial cap on the ps board (100uf 100v)...might as well do all of them :) (already did the filter)

I'll get to this tonight and see where I am.

Thanks

-tom
 
ok..rebuilt the high voltage section and got my displays up. I've removed the batteries so by flipping the switch once, we're into setup mode with the 04 in the master and the game number in display 1. a quick flip off /on gets me into game mode, if I go into self test, all lamps flash...displays advance and then solenoid tests try to fire (I have the solenoid fuse pulled on the psb at the moment due to the locked coil on the right slingshot bumper), so it looks as though it's working less the coil :)

So now I'm onto the coil. I've got the guide and will check it for troubleshooting, but is there a way to disable the coil so it won't pull and I can fire up the other solenoids to see if it'll run properly?

On a side note, I checked the resistance across the lugs and its at 3.74ohms ...so it's within the specs according the the guide... will dig deeper, but I'm close and totally geeked that its this close with minimal costs (knocking on wood).

thanks,

-tom
 
remove a wire from the coil....

ok..i kinda figured, but not really understanding how the coil works, wanted to make sure disconnecting wires didn't cause some other type of issue.

I snipped the black wire from the lug and booted up. I can run a solenoid test now and most sols pull. I can credit up the game, but can't start it. also, in test mode, while going through the solenoids, it gets to the speech and it's VERY faint..I can hear it..but only barely, but the preceding sounds are nice and loud. Any help or explanation as always is appreciated

thanks
 
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ok..i kinda figured, but not really understanding how the coil works, wanted to make sure disconnecting wires didn't cause some other type of issue.

I snipped the black wire from the lug and booted up. I can run a solenoid test now and most sols pull. I can credit up the game, but can't start it. also, in test mode, while going through the solenoids, it gets to the speech and it's VERY faint..I can hear it..but only barely, but the preceding sounds are nice and loud. Any help or explanation as always is appreciated

thanks

The potentiometer on the speech board controls the ratio between sound and speech. It's likely this just needs to be spun around a few times to clean, and then adjusted to your preference.

As to not being able to start a game..... test the 3 ball trough switches and the shooter lane switch in the diagnostics. If the machine isn't detecting all 3 balls, it won't start. And test using actual pinballs, not just pressing with your finger, you can get false readings just finger testing them.

-Hans
 
The potentiometer on the speech board controls the ratio between sound and speech. It's likely this just needs to be spun around a few times to clean, and then adjusted to your preference.

As to not being able to start a game..... test the 3 ball trough switches and the shooter lane switch in the diagnostics. If the machine isn't detecting all 3 balls, it won't start. And test using actual pinballs, not just pressing with your finger, you can get false readings just finger testing them.

-Hans

Wow... very cool. was able to play a game without the right slingshot and without speech..or at least speech with any volume. If I turn the pot all the way counter clockwise, I get no game sound and I get very faint speech, I can turn the dial clockwise and the game volume can get extremely loud, but at that point I can't hear any speech at all. So speech is working...I just cant get any volume on it..as for starting the game...only had one ball in it... added the other two and it started right up :)

I now remember why I love this game though...cant wait to figure out the speech volume issue.

Thanks again Hans, greatly appreciated!

-tom
 
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