Burnt diode on AR1

ieure

Well-known member

Donor 2014-2015
Joined
Feb 12, 2010
Messages
6,596
Reaction score
986
Location
Portland, Oregon
I pulled the PS & AR1 from my Asteroids to recap after recapping the monitor didn't solve my problem. One of the diodes on the AR1 is burnt up, and the Bob Roberts kit didn't have a replacement. None of the components on the board are labeled, so I don't know what to replace it with. Of the two between J6 & J7, it's the one next to J6.

I understand this indicates that I should repin the molex that goes to the PCB. I have no idea how to do this — is there a handy guide somewhere? My Goog-Fu shows lots of stuff to repair the traces on the PCB edge, but nothing about replacing the Molex housing.
 
OK, going to teach you how to fish, rather than just answer your question...

1) Go to http://arcarc.xmission.com/ and bookmark the page, because it has 90% of the arcade tech documents you'll need.

2) Because your game is an Atari, click on "PDF_Arcade_Atari_Kee"

3) It's Asteroids, so click on it on the next page.

4) Now you'll be presented with a dizzying array of documents. A quick primer on Atari nomenclature: DP = drawing package (schematics) and TM = technical manual. Scroll down to the "TM" documents. Notice that there are 7 different printings... that happened on the most popular games (less popular ones only had 1 printing). I usually start with the latest printing, unless I know my game is an older rev, and an older printing is appropriate.

5) Click on "Asteroids_TM-143_7th_Printing.pdf" and open it with your PDF viewing program. I recommend slowly reading every word on every page, because Atari made excellent manuals, chock full of good information.

6) When you get to PDF page 38, you'll notice that it is a picture of your AR1 (which Atari called the "Regulator/Audio PCB Assembly.") If you zoom in on the top-right corner, where your subject part is... you'll realize that this scan sucks...

7) So close it and open the "6th Printing" version.... go to the same page, and zoom in again. You'll see the diode very clearly identified, by call number and part number. On the next page is a parts list, which has more information about the components on that board.
 
Last edited:
You can get both of those at the Shack. 1n4001 diode (cr2) and for the other (cr1) you can use part number 276-1114 type PTC205 which is also a 2.5 amp 1000 volt rating
 
OK, going to teach you how to fish, rather than just answer your question...

1) Go to http://arcarc.xmission.com/ and bookmark the page, because it has 90% of the arcade tech documents you'll need.

2) Because your game is an Atari, click on "PDF_Arcade_Atari_Kee"

3) It's Asteroids, so click on it on the next page.

4) Now you'll be presented with a dizzying array of documents. A quick primer on Atari nomenclature: DP = drawing package (schematics) and TM = technical manual. Scroll down to the "TM" documents. Notice that there are 7 different printings... that happened on the most popular games (less popular ones only had 1 printing). I usually start with the latest printing, unless I know my game is an older rev, and an older printing is appropriate.

5) Click on "Asteroids_TM-143_7th_Printing.pdf" and open it with your PDF viewing program. I recommend slowly reading every word on every page, because Atari made excellent manuals, chock full of good information.

6) When you get to PDF page 38, you'll notice that it is a picture of your AR1 (which Atari called the "Regulator/Audio PCB Assembly.") If you zoom in on the top-right corner, where your subject part is... you'll realize that this scan sucks...

7) So close it and open the "6th Printing" version.... go to the same page, and zoom in again. You'll see the diode very clearly identified, by call number and part number. On the next page is a parts list, which has more information about the components on that board.

I appreciate this, but I do already have all the manuals and schematics for my games —*I am just new to working on them and want to make sure I don't make things worse. And in this case, the component was destroyed, so I couldn't see what it was, and it wasn't labeled, so I couldn't reference the schematic. I was hoping to get some advice from someone who had encountered this before, rather than trying, doing the wrong thing, and ruining a board.

I deduced the correct components by matching up where they connected with the schematic, then replaced R24, R25, and CR1. I fired it back up and it didn't explode, so it must be mostly correct.
 
Back
Top Bottom