Moving on to Solonoid Driver Board

[deep six]

Finally got the rectifier board finished and mounted back in the machine, had a few issues with crimping the new terminals on. At first I couldn't get the crimper to clinch down hard enough on the terminals to make a good connection, so I figured I would just add some solder to make sure, a bit later on I discovered (by accident) a second notch in the crimping jaws which made the crimps perfect. Guess I should have studied crimping 101, although one might expect a set of crimpers to come with some sort of guide.

Anyway, board is in, fired up machine and still don't have any solonoids to speak of.
I was expecting this but figured I would start with the rectifier board and get that working perfectly and progress from there.
None of the slingers work or the ball return solonoid, the only thing that kind of works are the pop bumpers, you can hear a very lethargic kick from them when the ball hits them so something is connected.
I did note the lighting seemed a little better, not sure if I m imagining it but the globes seem to burn steady and a little brighter.
Here is a pic of the rectifier board back where it lives.


Now, onto the solonoid driver board, here is a pic of it in situ just before I removed it, first remover plugs and marked them for future reference.


I have a rebuild kit here I got from Big Daddy at the same time as I got the rectifier board component kit.
I opted for the kit number 3, plus I supersized this kit, supersize sounds so cool so why wouldn't you want this.
I also got an IC kit just for the hell of it. I figured if I'm halfway through this rebuild and I find I need one small thing, its a long way to go to get it.
Now what has me wondering is the kit comes with     
* 20 ea. TIP102 Driver Transistors
* 30 ea. 1N4004 Silicon Rectifier
* 20 ea. 330 Ohm, 1/4 Watt Resistor
plus the supersize kit gave me an additional 9 of the above plus 9 of  0.002 uF, 2000 Volt Disk Capacitor.
But looking at the driver board there are a whole lot more resistors than what I have, and they seem to be of a different value whereas the ones I got seem to be all the same.
I'm wondering if I'm just supposed to replace some of the resistors but have no idea which.

here is a pic of the solonoid driver board with spare parts laid out along side.

[dj10555]

The rectifier board looks like it has come up well. With the solenoids not firing, you could check that you have 43vdc between one of the coils legs and a ground point. This will confirm the rectifier board is working fine and the connectors are good. The spare transistors, diodes, resistors are useful if you have a 1-2 of coils not firing or are locked on but since you have most of the coils not firing there might be another cause. Sometimes dry joints on the back of the J4 solenoid board heades or in the plug itself will cause this problem. Also worth checking is J4 connector on the MPU board, that there is no corrosion around here.  Hope this helps.

regards Derek

[Strangeways]

Under the playfield, there is a 1 - 1.5 Amp SLOBLO fuse. Check that the fuse and the fuse holder are ok. This is a Stern Galaxy ?

The relay on the transformer board is for the GI. In attract mode, this activates and all the GI flashes - is this working ?

[deep six]

Hi Derek

Thanks mate, I was about to go nuts and rebuild the solonoid driver board, still needs doing as I can see the large capacitors are on the bulging side but guess I should work out where the fault lies first.
I just put the solonoid driver board back in and will shortly test for 43 volts but......

Nino

(this is the Stern Galaxy)

I just checked the under playfield fuse and it is indeed burnt out.
I didn't have a 1 amp slo blo here, I read somewhere you can substitute a 2 amp quick blo fuse but didn't have any of those either. I found a 1 amp quick blo and a 3 amp quick blo.
Decided to fit the 1 amp quick blo and see what happened.

Fitted the fuse, plugged the machine back in and heard a solonoid fire for a split second then blissful silence.
So it would seem from what I have been reading that I have a locked solonoid. I don't know which one it is and not sure how to figure out which is at fault.
I guess its a matter of checking resistance with a multi meter but not sure what to look for.

On a side note, when I first looked at the machine, and first powered it up there was a horrendous noise coming from inside that sounded like an extremely noisy transformer.
A mate of mine visited the site before my next visit and found the thumper solonoid was hammering away at a great rate so he simply cut the wire to it. Stopped the noise but didn't cure the problem.

[dj10555]

The 1A fast blow fuse will probably blow. There is probably have either burnt coil / shorted transistor or both.  80% of the time you can find a faulty coil by either looking at them as seeing if they look burnt or try to move the plunger on the coil and see if it jammed/melted solid. If you have a meter, set it to resistance and measure each coil. Anything less than 3 ohms is normally faulty.

Once you have located the faulty coil, you can either find which transistor drives this coils from the schematic ( nd then replace the transistor and associated parts from your kit) or measure all the transistors with you meter to determine the faulty one. If you have a diode tester on your meter you can check every tranistor on the board in about 2 minutes.

Definitely worth changing the 2 large capacitors on the solenoid board (and perhaps also rebuilding the 5v and HV PSU) if the game is a keeper.

Were the pop bumpers still working when then the fuse was blown?

[deep six]

Thanks Derek

I tested all the solonoids and they all seem to read about the same resistance. They all look to be OK but I will go back and give the plungers a wiggle as you mentioned and see if anything obvious is up.
I killed my good multi meter a while back when I was measuring the test points on the rectifier board. I'm back to using my old DSE bar graph multi meter which works but is a little hard to read.
I think my DSE multi meter shouold be able to test the transitors, will check that out. I gotta get a new meter but thats another thing.
I'm planning on rebuilding the HV section of the board, not sure if this machine is a keeper but it certainly is giving me some good knowledge and experience.
As for the pop bumpers, they seemed to be working but only just, I'm not sure if this is possible with the playfield fuse out so maybe I was just imagining it.
Oh, how do I test the transistors?? can this be done on the board??

Cheers

Ric

[Strangeways]

I would ensure the fuse under the playfield is replaced with the correct value (a SLO BLO Fuse - 1.0 or 1.5 Amp) before doing any further testing. If the coils are all good, you can put the game into test mode and run the solenoid test.

[deep six]

Thanks Nino

I just got some slo blo fuse from jaycar, 1 amp and 1.5 amp, I also got a circuit breaker to trouble shoot the system, I read about using these on another post.
Lowest value circuit breaker I could get was 3 amp, is this going to be to high to trouble shoot the under playfield fuse??

I can't check the solonoids in diagnostics, as soon as I power up the machine the new fuse blows. I think the coil that resets the drop targets is at fault, it looks pretty crispy. Although it reads about 5 ohms with my multi meter, however I suspect my old multi meter is not reading true as it rates all the coils at approx 3 ohms which suggests they are all buggered, could be I suppose but hope not.
My new Fluke multi meter should be here in a few days so I can do some serious testing then.

[Homepin]

If you suspect a coil (such as the drop target reset coil) disconnect it and fire up again.

[Strangeways]

I would wait until you have an accurate meter (in a few days) and retest each coil. If it blows on power on, it will be a coil.

[deep six]

Thanks Homepin.

I did disconnect the power wires from the drop target coil but still blowing the fuse, I wondered if there was a problem on the solonoid driver board that is still causing the fuse to blow. Its all a learning curve for me.

But probably should wait til I get my new fluke meter as nino suggested and get a proper reading on all the coils.

As always, many thanks to you guys for taking the time to answer my questions and give me pointers. Very much appreciated.

Cheers

Ric

[deep six]

well guys, I finally got my new Fluke multi meter, only took two weeks to get here after I had paid for it.
Tested all the coils and found them to be withing tolerance, except for the drop target reset coil which I knew would be bad, have already clipped off the two yellow wires to this.
Pulled the Driver board out and checked all the transistors but to my surprise these were all within specs.
I'm now back to square one. I replaced the under field fuse with a slo blow of 1 amp, it lasted a few milliseconds more and then blew. Right now I'm at a dead end, not sure where to go  from here.
Should I have totally disconnected the drop target coil instead of just clipping off the yellow power wires??
Any suggestions??

Cheers

[Skybeaux]

You've got a short somewhere for the fuse to be blowing like that.
Check the coils are wired right , with the power wire to the banded side of the diode.

Being in Newcastle your not all that far from me , if you think the driverboard is at fault your welcome to come around and we'll put it on my tester to see how it is.

[deep six]

Thanks Ken

Will see how I go tracing a short.
I did note that once a new fuse is fitted, and I power it up I can hear a solonoid firing and then the fuse blows, I can't get up from the power point quick enough to see which coil is firing, (someone has removed the mains switch that usually lives under the cabinet).

[Boots]

Thanks Ken

Will see how I go tracing a short.
I did note that once a new fuse is fitted, and I power it up I can hear a solonoid firing and then the fuse blows, I can't get up from the power point quick enough to see which coil is firing, (someone has removed the mains switch that usually lives under the cabinet).

Get yourself a powerboard with individual switches and with the playfield up flick the switch while standing next to the machine.
If you want a bit more time to see you could put a 2 amp slo-blo in there and quickly flick the switch on then off.
This will probably allow you a few goes without blowing the fuse but you should see which coil is firing.
Also check none of the diodes on the drop target are bent over and earthed out, this can cause heaps of screwy sh?$*t.
I you can see the general area where the coil is you may have to disconnect all the coils in that area and re-connect them one by one.