30-year-old electrolytic capacitors should always be changed, especially on a power board. Diodes should be changed if they fail tests or look swollen or melted. Transistors should also be checked.

For cleaning, I've been spraying simple green on a toothbrush, then scrubbing the affected area, rinsing with water, and then with 91% isopropyl alcohol. Blow dry with an air compressor around 30-60 psi.

The life expectancy of an electrolytic cap is more a function of run time (plus heat, size and some other factors) rather than how old they are.

http://www.cde.com/tech/reliability.pdf

Here ya go...
http://www.pinwiki.com/wiki/index.php?title=Gottlieb_System_80#Recommended_Updates_and_Repairs_for_the_System_80.2F80A_Power_Supply_Board

You can simply scratch that solder flux off the board. Or you can use a solvent like naphtha and a light wire brush.

The insulator can still be used. It's there to isolate the transistor leads from the cold plate.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

For the insulator -- use a MicroPlastics 18PTI1HDWOB as found here:
www.greatplainselectronics.com/products.asp?cat=136
Perfect fit.
Or just shove the pads of the broken one you have back into place and reuse...it'll work fine.

Caps age is definitely a function of age AND run time. Yes, a cap sitting on a shelf and never used can also go bad with time...just takes longer. I've found that the smaller caps (e.g. 1uF sound board caps) will go bad with age even with very little use. Large computer grade caps tend to have longest life spans unless they are overdriven.

Ed

Nice work, coming along just fine. Yeah double sided tape, silicon caulk or hot glue would work too.

See how one leg of the LED is longer, or the plastic body has a flat side?

Polarized caps have a (+) on the circuit board.

direction will not matter for those.

oh and you may want to take a piece of cut off resistor lead and form a loop and solder to test points. this way you can easily hook a test lead on at a later time.

Those are probably testing out of spec because you are testing them in circuit.
Resistors don't fail that often.
I'd connect the input power then measure the outputs.
It may be good to go.

Don't forget to put the LM723 in.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

looks like the socket is upside down? the notch and the dot on the pcb show the end that is pin one

Yes it does. There are pictures in the System 80 sections of the PinWiki that will help.
The "notch" goes down.
System 80/80A power supply. Pic from PinWiki.com
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

There is really no need. The white dot silk screened on the board will be enough to indicate pin 1.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

Yup. Repairable. It'll be a bit of work.
Neutralize the alkaline corrosion first.
Does it boot?
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

the flux residue not cleaned just use ipa and a soft toothbrush. you have two of the RIOTs socketed nice. not much damage at all board looks nicer than any of mine so you might as well go buy a new one and send those to me.

So you built the PS and what NO readings? At least give us the no load voltages, before you think you are done with that board.

Not the original CPU board, that looks like it's from an 80A (7 digit) since U2/3 are socketed and they look like they've never been touched. I can't remember if anything needs to be jumpered for it to work with 6 digit A2/3 and game ROM, anyone know? Since the CPU is replaced (probably due to major alkaline damage), I wouldn't trust any of those connector crimps at A1J1, A1J4, A1J5 & A1J6. I'd replace them all before trying to troubleshoot that board. It's also missing a capacitor (C26) at Z19.

Steve

The fat trace that loops around the positive battery connection has light alkaline damage.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info

Hey Force - any tips on desoldering Q3 without destroying it? I want to get at the solder side of the board to do a refurb. Is Q3 worth preserving or should I just cut it out?

Add some new solder to the old solder, then use a desoldering iron to suck everything out. Then unscrew it and (gently) remove it from the PCB. If you try to pull too hard without getting all the solder, then you might end up pull out the eyelets.

Awesome, as per usgh, Force - thanks. I managed to get it off before reading this by adding and removing as much solder (with a solder sucker) as i could then held the iron on both leads while gently prying, and it eventually let go. The top eyelets are fine, but I may have lost one on the back?

I'll have to look in to this "desoldering iron" you speak of.

Thanks again - Paul

Take a look at the Hakko FR-300 or FR-301. It's light years better than a spring loaded solder sucker. I made the switch years ago and haven't looked back since.