(Topic ID: 291202)

BSD Column 8 Switch issues

By Aphex

3 years ago



Topic Stats

  • 8 posts
  • 4 Pinsiders participating
  • Latest reply 3 years ago by Aphex
  • Topic is favorited by 1 Pinsider

You

Linked Games

Topic Gallery

View topic image gallery

8DEFE0C9-A175-42E9-9607-08CD1F887EB4 (resized).jpeg
AB711034-6A11-433D-9A6C-FED7C48858B6 (resized).jpeg
24FD2EEA-C39A-4411-9923-F04FA35486F4 (resized).png
16.jpeg
5D22A89A-8E06-43C2-8B64-18E7E2FFF412 (resized).jpeg
73CA7B22-71B3-47B5-B59A-E13E8E8E01F5 (resized).jpeg
BSD Switch issue (resized).png
#1 3 years ago

Picked up a BSD today there are switches that are not activating in switch test. The 3 center targets, the magnet switches below the playfield. Attached the column list for the rest. there is continuity from J-207-9 to the green wire of all of the switches. on the board i have 12 volts at all the pins on J-207. (rules out a potential U20-11 problem?) any other ideas or places i should be checking out? thanks for any help!

BSD Switch issue (resized).pngBSD Switch issue (resized).png
#2 3 years ago

To add... I helped Aphex bring this home and set it up. I think the voltage was on J209, not J207... but I’m not standing at the machine at the moment.

#3 3 years ago

U20 is faulty...you are measuring the wrong Connector

#4 3 years ago
Quoted from WH20_Buzz:

U20 is faulty...you are measuring the wrong Connector

What do you suggest we should be checking?

#5 3 years ago
Quoted from WH20_Buzz:

U20 is faulty...you are measuring the wrong Connector

My friend noticed a small mark in the Upper right hand corner of U20!

5D22A89A-8E06-43C2-8B64-18E7E2FFF412 (resized).jpeg5D22A89A-8E06-43C2-8B64-18E7E2FFF412 (resized).jpeg73CA7B22-71B3-47B5-B59A-E13E8E8E01F5 (resized).jpeg73CA7B22-71B3-47B5-B59A-E13E8E8E01F5 (resized).jpeg
#6 3 years ago

Measuring 12v does not rule out the ULN2803 at U20. All the output lines of U20 are pulled high to 12v through a 1k resistor. The ULN will pull that line down to 0v when it drives it and let the 1k resistor pull it back to 12v when it is not driven. I don't see a huge mark on the upper part of U20 , but that doesn't look like real physical damage. Do you have continuity between pin 9 of J207 and pin 11 of U20 (red line in pic).

I see corrosion on the battery post , any corrosion below it at all ? no matter how small? Pictures look clean except for a blue glow in one of the pics , but it looks like a camera reflection.

On the picture, ULN receives the signal for column 8 on pin 8, in yellow, outputs it to pin 11 , the red line. Both green marks are the power of the chip, which is far from the mark on the upper right. If you have a logic probe, you can verify easily both pins 8 and 11 of the ULN. You might be able to test it with a multimeter only but most meters don't react fast enough to really see a change, but some do. Analog ones would. These pins are constantly driven at a regular interval. The ULN inverts the signal as it drives the output. On pin 8 you should measure 0v until it receives a 5v pulse. On pin 11 you should measure 12V until it pulses to 0v quickly.

No reason to type more than as already been explained, just read this post:

https://pinside.com/pinball/forum/topic/terrybs-guide-to-logic-probes#post-2514877

Most likely U20 really is faulty. It's a very common part and should be fairly easy to change , especially when you don't care about salvaging the part, for the rookies cutting the pins and removing the chip, to then desolder each pin one a time by pulling them out yields the cleanest results. Rule of thumb , if you change an IC , install a socket.. It costs cents and can save headaches down the road.

16.jpeg16.jpeg
#7 3 years ago
Quoted from Roamin:

I don't see a huge mark on the upper part of U20 , but that doesn't look like real physical damage.

A better pic of his U20 is attached.

Quoted from Roamin:

Do you have continuity between pin 9 of J207 and pin 11 of U20 (red line in pic).

If he can’t do that himself, I’ll check in the next few days and get back to you.

Quoted from Roamin:

I see corrosion on the battery post , any corrosion below it at all ? no matter how small?

No corrosion evident on the board. Could be some under the battery holder, but it hasn’t migrated downwards at all.

I have a logic probe. Not sure I understand what you’re asking us to do, but I’ll give it a try.

24FD2EEA-C39A-4411-9923-F04FA35486F4 (resized).png24FD2EEA-C39A-4411-9923-F04FA35486F4 (resized).png
3 weeks later
#8 3 years ago

Just an update, been busy getting the game cleaned up forgot to post. CPU board was sent out for NVRam, U20 was the culprit as everyone mentioned. The chip has been socketed for any future failures. Thanks for all the help and advice, I’ll know what to look for going forward should a chip have an issue!

8DEFE0C9-A175-42E9-9607-08CD1F887EB4 (resized).jpeg8DEFE0C9-A175-42E9-9607-08CD1F887EB4 (resized).jpegAB711034-6A11-433D-9A6C-FED7C48858B6 (resized).jpegAB711034-6A11-433D-9A6C-FED7C48858B6 (resized).jpeg

Promoted items from Pinside Marketplace and Pinside Shops!
$ 399.00
Cabinet - Decals
Mircoplayfields
 
$ 9.99
Eproms
Matt's Basement Arcade
 
$ 259.99
Cabinet - Toppers
Lighted Pinball Mods
 
$ 18.95
Eproms
Pinballrom
 
4,900 (Firm)
Machine - For Sale
Hudsonville, MI
$ 329.99
Lighting - Other
Lighted Pinball Mods
 
$ 17.50
Cabinet - Other
Rocket City Pinball
 
$ 109.99
Lighting - Led
Lighted Pinball Mods
 
5,900
Machine - For Sale
Hudsonville, MI
$ 449.00
Cabinet - Decals
Mircoplayfields
 
$ 30.00
Playfield - Other
Lenticular Designs
 
5,000
Machine - For Sale
Olive Branch, MS
$ 46.99
Lighting - Interactive
Lee's Parts
 
$ 10.00
Cabinet - Decals
Pinball Haus
 
$ 69.50
Boards
Pinball Haus
 
From: $ 25.99
Lighting - Led
Lee's Parts
 
$ 225.00
Cabinet - (Alt) Translites
FlyLand Designs
 
$ 49.99
Cabinet - Toppers
Lighted Pinball Mods
 
$ 17.50
Cabinet - Sound/Speakers
Pinball Haus
 
$ 19.95
Playfield - Protection
SilverBall Designs
 
$ 25.00
Playfield - Toys/Add-ons
Rocket City Pinball
 
$ 119.99
Cabinet - (Alt) Translites
FlyLand Designs
 
$ 1,059.00
Flipper Parts
Mircoplayfields
 
$ 27.95
Eproms
Pinballrom
 
$ 5.00
€ 45.00
Playfield - Toys/Add-ons
Kami's Pinball Parts
 
From: £ 30.00
Playfield - Toys/Add-ons
RudeDogg Customs
 

Reply

Wanna join the discussion? Please sign in to reply to this topic.

Hey there! Welcome to Pinside!

Donate to Pinside

Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!


This page was printed from and we tried optimising it for printing. Some page elements may have been deliberately hidden.

Scan the QR code on the left to jump to the URL this document was printed from.