System 80 fuse F17 blows

[Guest]

Archived from groups: rec.games.pinball (More info?)

I bought my first pinball machine a coupe of days ago (Volcano
Gottlieb, system 80), so I'm really (really) new in that universe (and
in electronic). I tried the machine before buying it and everything was
fine. Unfortunately, after moving it at home, my machine doesn't work
well. Here is my problem:

The F17 fuse, who controls the ball release, blows everytime I start a
new game! I looked under the playfield for some unconnected wires or
bad soldering, but didn't find anything bad (using what I know in
pinball, not much). Just before moving the machine, everything was
working well. I guesse the coil is good since it works when I put a new
fuse. I know I could check the diode (but I must ask somebody because I
don't solder, maybe it would be better to learn ;-) ). Any other hints
about that problem?

Thanks!

klode16, eager to play a first game on my first machine!

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Sounds like a bad coil. Does it fire the one time and blow the fuse at
that same time?

zTim

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Hello,

it may also simply be the diode that is soldered across the lugs of the coil
in question, is bad. You will have to test the resistance of the coil, to
see if it is shorted, before you decide the diode is bad. If you could post
the part number for the coil I should be able to tell you what the specified
resistance is; otherwise if you have a manual for your game it should have a
table of values.

Good luck,
Dan

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Thank you for your advices. I'm gonna check tomorrow if the fuse blows
immediately after the ball release and also, check the coil. Dan, I
have the manual and the coil values, thank you.

I don't know if it could help, but i've been able to play games today
with the glass off. The only thing I had to do was to release the ball
by hand. The rest was working very well.

Work on it tomorrow...

Thanks!

Klode

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

I'm going on, on step at the time...

Here is what I did this morning, I hope the problem is narrowed a
little bit, but don't know what to do now...

I tested the coil at some places, as suggested in the Kirb's site.

http://www.geocities.com/kirbseepe/repairdriver.html

So I took a wire jumper connected to ground and touch the non-banded
side of the diode of the ball release coil. The coil fired et no blown
fuse.

I did the same at the connector A3J3 of the driver board, same result.

Again at pre-driver transistor Q16, same result.

Same thing at the playfield transistor Q1 (I touched the E I think)

So, you have an idea what could be the problem? Ground? CPU or driver
board?

Any suggestion will be welcomed! Thanks again!

Klode!

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Hi Klode,

I just realized another possible culprit. That coil (known as the outhole
coil) is driven by the Q59 transistor on the driver board--you will want to
confirm Q59 in the manual, because I am referring to a different system 80
game manual. If this transistor is bad blown fuses will occur, as well.

http://www.marvin3m.com/sys80/index.htm This is a terrific link to
introduce you to system 80 repair techniques.

Good luck, and welcome to the world of system 80!
Dan

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

What you did is Ok but somewhat dangerous for a game in an
unknown state. There is a better way to test coils, with
the power OFF. I highly suggest everyone do this on any
new-to-them game, before powering on for the first time.
Doing the following only takes a minute and can save some
repairs, especially if you are systematically repairing a game:
http://marvin3m.com/sys80/index1.htm#coils

Klode16 wrote:
> I'm going on, on step at the time...
>
> Here is what I did this morning, I hope the problem is narrowed a
> little bit, but don't know what to do now...
>
> I tested the coil at some places, as suggested in the Kirb's site.
>
> http://www.geocities.com/kirbseepe/repairdriver.html
>
> So I took a wire jumper connected to ground and touch the non-banded
> side of the diode of the ball release coil. The coil fired et no blown
> fuse.
>
> I did the same at the connector A3J3 of the driver board, same result.
>
> Again at pre-driver transistor Q16, same result.
>
> Same thing at the playfield transistor Q1 (I touched the E I think)
>
> So, you have an idea what could be the problem? Ground? CPU or driver
> board?
>
> Any suggestion will be welcomed! Thanks again!
>
> Klode!

 

[Guest]

Archived from groups: rec.games.pinball (More info?)

Here is what I did today and in the last few days : Problem not fixed
yet!

- Changed the transistor 2n5875 under the playfield
- Changed the diode of the "ball release" coil
- Tested continuity between PF Transistor and lower cabinet ground,
between the transistor and the coil, between coil and the fuse, between
the transistor and the driver board connector.
- Tested coil, seems ok (2,95 ohm) Does a good tested coil can be bad?
- Tested driver board transistor mps-u45 - ok
- I tested the signal (pulse) with my logic probe between the mps-u45
transistor and the U6 chip and followed the same path for the Fire Pit
(same way to fire the coil and working) - both seemed to be the same
- Looked under the playfield and didn't find loose wire...
- I used the good fuse - 2.5 A slow blow

The hole kicker still working when the fuse is good.

Thanks for reading...

Klode