Data East power supply problem

[Steevsee]

Is that thick trace going under R14/R15 burnt?  Looks burnt.

Also wonder why the extra cap on R14?

[Dimsims]

Yep that trace is burnt to high heaven 

[Steevsee]

R15 certainly has been getting hot!

How's the continuity between lh side of R15 (bottom in your pic), and banded end of D6?

[Dimsims]

I found this searching the net:

http://translate.google.com.au/translate?hl=en&sl=fr&u=http://www.flipjuke.fr/alim-data-east-perte-68v-apres-t92534-20.html&prev=search

Same symptoms as mine, but never found a solution 

[andtan]

Was having a look on the net re this problem and found the following link:

http://www.willcoxonline.com/pinball/

Scroll down to the heading: Dot Matrix Display stopped working.

Hope this helps.

Cheers,

Andy

[Strangeways]

R15 certainly has been getting hot!

How's the continuity between lh side of R15 (bottom in your pic), and banded end of D6?

If that is open circuit, then I would expect to see nothing at D6. Seems there might be some jumpering under the board that is incorrect.

[Steevsee]

Yes bottom side of board pic would be good.

The article linked by Andy (andtan) is also worth looking into, especially if any charring around TR3 C/E.

Dimsims
Sorry I didn't get those measurements today.
On days(Nights) off after tonight so will definitely get them done tomorrow.

[Dimsims]

Thanks Guys 

OH its charred alright 



I did some scraping off the black charred stuff and there ended up being a fairly big hole where TR3 goes.



TR4 not much better.

Now I have to think of a way to fix it lol.
So should I scrape as much of the charred stuff off the board ?

[Steevsee]

I wouldn't go too crazy scraping yet.
Basically bad charring produces carbon which can conduct between pads but most areas should be fine.

As far as the transistor goes you might get lucky as it's mostly supported by the heatsink.
You'll just need to jumper the legs to the relevant traces.

And leave TR4 alone.

[andtan]

If the heat sink doesn't do a good enough job of holding the transistor in place, you could look at using an epoxy such as JB Weld:

http://www.jaycar.com.au/Service-Aids/Chemical-Aids/Adhesives/J-B-Weld-Epoxy/p/NA1518

to fill in the burnt out area. You'd need to put something underneath the board to hold the epoxy in place as it sets - I've found that most clear plastics from product packaging works well for this - just tape it in place.

Then drill some new holes for the transistor and jumper the legs to the relevant tracks as suggested by Steevsee.

[Dimsims]

I've managed to get the Transistor to sit there with the support of the heat sink.

Plugged it back it the machine to test, now the R15 has stopped heating up, but only getting 5.8 volts on the 68 volt line 

I can feel a new board in the works lol

[Steevsee]

That seems like some good progress if that resistor is no longer overheating.

In the article, the guy's 68 volt zener got fried before he fixed the overheating issue.
Dare say the same thing has happened here.

Also the board looks OK overall, but probably worth dealing with that hole once it's all working.

http://aussiepinball.com/index.php?topic=7422.0

[Dimsims]

In the article, the guy's 68 volt zener got fried before he fixed the overheating issue.
Dare say the same thing has happened here.

Will give that a go, I just found my spare 68v zener that I had 

Also I now need a 1N5379 110v zener as I blew it last night lol
I was testing something near it slipped out it and shorted & killed the D10 110v zener 
Trouble is where do I find one ? Jaycar & RS Components don't have them ?

[Dimsims]

I replaced the 68 volt zener, did another test & got 66.8volts 

Now just need to find a 110volt zener for D10 

[DSB]

  I've been keeping up with this thread with interest. It wasn't looking like a good result there for a while. Will you look into fixing that hole now or let it be?