BlahCade 93: Circuits and Gaps

http://blahcadepinball.com/2017/03/28/Episode-93-Circuits-and-Gaps.html


This episode centers around a lot of techy IRL pinball talk. We talk mostly about a Bally Power Module board that is showing it’s age. Then we move into the digital realm with the latest FarSight news.

Re: beta bug lists, a shared list on say github might be an idea?

EldarOfSuburbia said:

Re: beta bug lists, a shared list on say github might be an idea?

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I'd be ok with that, but we would need to set this up with FarSight.

jaredmorgs said:

I'd be ok with that, but we would need to set this up with FarSight.

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Yeah thinking out loud... maybe best to move the discussion over to the G+ group.

SCIENCE! it's too bad that tune became a bittersweet yoke on dolby's shoulders... back then, it was just 'tha thing' if you wanted to get a bit of pop-top 40 attention, to do something a little bit "novelty"-sounding ("video killed the radio star" and all that back then!)

though he has an intrinsically weird and nerdy sense of humor, dolby's a lot, lot more musically/melodically talented than just that one signature track. check this one out:

thomas dolby - commercial breakup

(if you decide to want to hear more at the end of the vid and choose "radio silence" from the menu, when the youtube page pops up, you should instead choose the "guitar version" that'll appear in the right column... the original was a bit artsy-fartsy "art of noise" sounding; the "guitar version" redo is much better, and also "more eighties than eighties" - aka, a more timeless-sounding version.)

i swear, some days when the mood strikes me (especially if i'm in a bad mood, and wanna get in a good one), i put that on repeat play two or three times... never fails! it's so steely-dan smooth and ginchy. it's one of those "eighties" tunes that says, "all you other so-called eighties songs? just try to sound -this- good..."

if you like that one, try his album "aliens ate my buick" - it's one i always thought would be excellent for killing time driving thru the desert, la-to-vegas with the top down in the twilight of the day (i've always thought "budapest by blimp" from that one is one of the most beautiful tunes ever recorded.)

p.s. trivial pursuit: next time you hear anything off of foreigner's "four" album, listen for the dolby keyboard treatments! he paid to make his "SCIENCE!" first album, "golden age," off of what he made doing up their tracks in studio.

foreigner - i've been waiting

I haven't listened to this ep. Yet. But, if Chris has some questions about Bally Power Supply's for -35 games, hit me up. I'll help where I can. I completely rebuilt my PM on my Centaur. EVERYTHING except the connectors were replaced.

dtown8532 said:

I haven't listened to this ep. Yet. But, if Chris has some questions about Bally Power Supply's for -35 games, hit me up. I'll help where I can. I completely rebuilt my PM on my Centaur. EVERYTHING except the connectors were replaced.

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That's definitely non-trivial. Good work on getting the thing working. It's really important to get good clean voltage on these vintage boards.

I'm sure Chris has received some answers by now. But, they're very few parts on the power module board. Replacing them all would not be considered a shot gun type method because this board takes a lot of abuse. He really should get (or borrow) a soldering station to manage the temperature. Very important in board work to not go too hot. Also, Hakko makes a gold Brillo pad like sponge that's great for keeping the soldering tip clean.

Pinballninja.com is a fantastic video site maintained by Clay Harrell with hundreds of repair videos. A small, one time, donation gets you a password forever. He should look at every relevant Bally repair video even if it's not for EBD.

Regarding the board itself, the four large diodes are for maintaining the 5v for CPU operation. They're stressed all the time. That's why the board is black underneath. The two square components under the board are bridge rectifiers. These are basically four diodes wrapped together in a little box to covert AC voltage to D.C. voltage. One is for the coils and the other is for the CPU controlled lights. They may have a heat sink paste on them and are pressed against a large metal plate that the board is attached to. This acts as a heat sink. The red lollipop looking thing is a varistor. Basically a little surge protector for the board. There's another one of these components attached to the little metal box that the line cord is soldered to on the side of the cabinet. Be careful around here as this is wall voltage coming into your game with absolutely no safety precautions in mind. The five little diodes with the "high voltage" marking around them manage the DC voltage for the displays. This is wall voltage in this section so you can get shocked. The two white rectangle things are cement resistors. Each one travels to a bridge rectifier to control voltage. That's all the components other than fuse holders and connectors. Make sure the fuse holders are tight and clean along with the connectors. One other thing. Learn soldering. Less is better. Don't glob it on. Avoid bridging two solder points. Be sure that this game has more than a few cold solder joints. Make sure your power supply is sending the correct voltage. Sure you can buy new boards for the back box, but, if you damage one with incorrect voltage, the manufacturer will probably not honor the warranty.

Hope this helps some and sign up with Pinballninja.com. Watch ALL his Bally -35 repair vids. They will help.

Thanks for the board explanation [MENTION=320]dtown8532[/MENTION]

That was interesting for me.

Off air I already stressed the value of a Pinball Ninja subscription to Chris.