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Arcade and Pinball Discussions => Beginner's Help Corner => Topic started by: JohnMc on May 27, 2017, 01:35:05 am



Title: My Robotron project from Victoria, BC, Canada
Post by: JohnMc on May 27, 2017, 01:35:05 am
The first thing I did was blow and vacuum the thick layer of dust within the cabinet.  I didn't even test the power coming in because, the power board was screaming for some love and attention.  All the fuses were out and one was even wrapped in tinfoil and as it turns out another was replaced with a higher amp valve!  I'v spent a few evenings of reading about my new Robotron project.  I cam across the site http://arcarc.xmission.com which is so big I searched like this, "site:http://arcarc.xmission.com robotron".  Yesterday I began to start testing the power board, "D-8784 Power Supply Board Assembly Drawing" in accordance with, sheet 8 from the document Williams, ROBOTRON: 2084 16-P-3005-103 Aril 1982.  Everything listed below, in red is a failed part.

One question I have is the 2nd column in the electrical drawn set looks like Nato Sock Numbers, is this true?  for example: 5010-09314-00
(https://mail.google.com/mail/u/0/?ui=2&ik=a50d47430b&view=att&th=15c484adcfa91cb5&attid=0.1&disp=safe&realattid=1568524423875526656-local0&zw)

(https://mail.google.com/mail/u/0/?ui=2&ik=a50d47430b&view=att&th=15c4840f693d5d56&attid=0.4&disp=safe&realattid=1568523671869325312-local3&zw)
I'll test the Caps tomorrow as soon as I can find the ESR values and be ready to order the new parts Monday.
(https://mail.google.com/mail/u/0/?ui=2&ik=a50d47430b&view=att&th=15c488082c0f156a&attid=0.1&disp=safe&realattid=1568528123953152000-local0&zw)
(https://mail.google.com/mail/u/0/?ui=2&ik=a50d47430b&view=att&th=15c488082c0f156a&attid=0.2&disp=safe&realattid=1568528123953152000-local1&zw)


I'll check back in with a status report when I have one, sincerely, John


Title: Re: My Robotron project from Victoria, BC, Canada
Post by: JohnMc on June 18, 2017, 12:15:11 am
Well, here’s a update to my progress:

I went to the local electronic shop and they looked at my marked-up/redlined drawing and compared that to the pictures I had of the board and told me to only replace the electrolytic capacitors for now!   I ordered all new capacitors and received all but 1.  When I went to remove the capacitors I found out that my cheap Radio Shack solder sucker, just sucks at removing solder (it couldn’t remove enough solder). 

I went back to the electronic shop and they sold me a deluxe SOLDAPULLT (DS017) and gave me some handy tips.  Just before I started to de-solder the board I went and looked to see if I could get any additional tips on youtube and came across, “HOW TO SOLDER - Arcade Tech - Soldering Basics, Monitor Cap Kit, Desolder, etc.” on Joun’s Acade Game Reviews & Tech!



Here’s my method that seemed to work for me:

-Re-solder the joint before you start to remove it.  This introduces new clean filler material so, you’re not working with 35 year old solder!!

-I kept my new, “SODAPULLT” handy so, as soon as I added the new filler material I grabbed it and placed the SODAPULLT tip as flush to the work piece as possible.  This would require me to have my solder iron as close, A.K.A., parallel to the PCB board as possible and at the same time having the iron tip contacting the joint as much as possible.

-Then as soon as possible, activate the Sodapullt and remove as much of the solder within the joint as possible.  To my surprise sometimes the component would actually fall out of the board; however, most times I’d have just take the iron and place it on top of the leg of the component and apply slight pressure, while sometimes pulling the piece out.  This would take minimal effort.

I’m going to wait for my last capacitor to come in and then start to solder the new parts in.


I also made a, “dim bulb tester” so I can gently power up the machine and not short out anything if I still have outstanding issues!  I should have the linear power supply running soon.  I can hardly wait.

JohnMc ;D


Title: Re: My Robotron project from Victoria, BC, Canada
Post by: allansim on June 18, 2017, 06:43:01 am
Thanks for the report. Would love to see some pictures!


Title: Re: Re: My Robotron project from Victoria, BC, Canada
Post by: JohnMc on June 18, 2017, 10:02:49 am
Thanks for the report. Would love to see some pictures!
I'll try and get some this evening