Possible fried chips on Apple II+

17 posts / 0 new
Last post
Offline
Last seen: 3 years 3 months ago
Joined: Sep 5 2013 - 16:49
Posts: 51
Possible fried chips on Apple II+

I picked up a pristine II+ years ago but the original owner says that he thinks he fried a ROM chip and possibly others... I have never plugged it in, in fear that it would blow up on me Smile

I think that I'm ready to test it but I'm not sure if there's anything in particular that I should look for before I flip the switch... he also broke a leg off one of the ROM chips but I had that "professionally" repaired and placed back in it's slot.

Any suggestions before flipping the switch? I can send pictures this evening of anything needed...

Thank you,
Roger

Offline
Last seen: 3 hours 4 min ago
Joined: Dec 20 2003 - 10:38
Posts: 570
Re: Possible fried chips on Apple II+

I'd check the chips to make sure they're all facing the correct way. Other than that, I'd go for it.

Offline
Last seen: 1 week 6 days ago
Joined: Apr 13 2006 - 22:28
Posts: 147
Re: Possible fried chips on Apple II+

In addition to what Roger recommended, I would take the unit somewhere with very good ventilation, preferably outside. The capacitors in the power supplies dry up over the years and have a tendency of exploding with a foul smelling smoke that is hard to get rid of (ask me how I know!).

The good thing is, the capacitor that usually fails is a mains filter (removes any spikes from the mains) and is not required for the Apple ][ to run. They generally cause no harm either, apart from possibly spewing their foul smelling brownish-orange goo inside the PSU case.

The other good thing is - if this capacitor does explode, they are easy enough to replace (you can still buy the same type of capacitors today).

The only other thing I would recommend is maybe removing all cards from slots prior to the first switch on - this will have two side effects:
1) it ensure that a bad card doesn't bring the system down; and
2) if the system does have a problem, it won't damage the cards.

That's all I can recommend.

Other than that, switch it on and stand back! Smile

Cheers,
Mike

CWJ_Wilko's picture
Offline
Last seen: 1 month 4 weeks ago
Joined: Jun 2 2015 - 23:38
Posts: 289
Re: Possible fried chips on Apple II+

IMAGE(https://i.imgflip.com/1tqm6o.jpg)

Let us know how you go. I remember the same agony of anticipation a few years ago before I switched on my Apple //e.

Offline
Last seen: 3 years 3 months ago
Joined: Sep 5 2013 - 16:49
Posts: 51
Re: Possible fried chips on Apple II+

This is great, I can't figure how to post pics Blush Here's a Flickr link:

IMAGE(https://farm5.staticflickr.com/4335/36275113112_853c7dac93_k.jpg)20170808_063851 by Roger Dillon, on Flickr]Pic1[/url]

IMAGE(https://farm5.staticflickr.com/4417/36275097662_98fe2e0fd4_k.jpg)20170808_063859 by Roger Dillon, on Flickr]Pic2[/url]

macnoyd's picture
Online
Last seen: 1 hour 51 min ago
Joined: Oct 15 2012 - 08:59
Posts: 836
Re: Possible fried chips on Apple II+

Would it not make sense to relocate the ceramic memory chips all to the same row?
PCB looks pretty clean but it appears that ALL the RAM chips are installed BACKWARDS!!
If this Apple II has been powered up already, chances are there are a lot of dead RAM IC's...

Offline
Last seen: 3 years 3 months ago
Joined: Sep 5 2013 - 16:49
Posts: 51
Re: Possible fried chips on Apple II+

Please be patient with me on this.. which chips exactly need to be moved/rotated

Thank you,
Roger

macnoyd's picture
Online
Last seen: 1 hour 51 min ago
Joined: Oct 15 2012 - 08:59
Posts: 836
Re: Possible fried chips on Apple II+

Looks like ALL the RAM chips need to be removed and rotated 180 degrees. They are all in backwards.
Match up the Memory chip rows with 8 of the same looking brand IC's.
The notch on the chip should point to the same direction as the white dot on the board. (like all the other ICs)

Offline
Last seen: 3 years 3 months ago
Joined: Sep 5 2013 - 16:49
Posts: 51
Re: Possible fried chips on Apple II+

The 6502 chip looks upside down... is it OK the way it is?

Disregard... the notch on this one is already pointing to the white dot.

Thank you again

macnoyd's picture
Online
Last seen: 1 hour 51 min ago
Joined: Oct 15 2012 - 08:59
Posts: 836
Re: Possible fried chips on Apple II+

The 6502 IC appears to be installed correctly.

speedyG's picture
Offline
Last seen: 4 years 10 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Possible fried chips on Apple II+

Hello dafivehole,

I'd recommend to first read this pages:
http://www.appleii-box.de/D04_resurection.htm
and follow up precisely the instructions in this page step by step.

The page:
http://www.appleii-box.de/H198HomeRepairGuide.htm
contains further information..... beyond that page

sincerely
speedyG

Offline
Last seen: 3 hours 4 min ago
Joined: Dec 20 2003 - 10:38
Posts: 570
Re: Possible fried chips on Apple II+

The notches on all the chips should be toward the front(keyboard end) of the machine.

Offline
Last seen: 3 years 3 months ago
Joined: Sep 5 2013 - 16:49
Posts: 51
Re: Possible fried chips on Apple II+

OK, I removed all RAM chips and only replaced eight (all the same for 16K) in the front row. I flipped the switch... no beeps or sounds... just the picture below. Bad RAM chips?!?

IMAGE(https://farm5.staticflickr.com/4388/35644500613_cb2f2a2d60_k.jpg)AppleIIscreen by Roger Dillon, on Flickr]screen[/url]

Offline
Last seen: 3 years 3 months ago
Joined: Sep 5 2013 - 16:49
Posts: 51
Re: Possible fried chips on Apple II+

I just swapped out the RAM chips and nothing changed... of course the RAM chips I used could be bad too.

I pulled all of the RAM chips out and flipped the switch... the screen is covered with questions marks "?" and nothing else...

Well at least I know that it won't blow up when I turn it on... I'm going put all of the RAM back in it and throw it on eBay and sell it as "parts or repair" and be totally honest with potential bidders.

Thank you,
Roger

macnoyd's picture
Online
Last seen: 1 hour 51 min ago
Joined: Oct 15 2012 - 08:59
Posts: 836
Re: Possible fried chips on Apple II+

Or, you can make me an offer I can't refuse. Smile

Offline
Last seen: 3 years 3 months ago
Joined: Sep 5 2013 - 16:49
Posts: 51
Re: Possible fried chips on Apple II+

I sent you a PM. If anyone is interested before it hits FeeBay, please let me know.

Thank you,
Roger

macnoyd's picture
Online
Last seen: 1 hour 51 min ago
Joined: Oct 15 2012 - 08:59
Posts: 836
Re: Possible fried chips on Apple II+

Turns out that the F8 autostart ROM was bad. I don't know if the RAM in backwards would have damaged
the F8 ROM or if the backward RAM was a consequence of someone troubleshooting the issue. But the
computer is back to life now with period correct RAM (all ceramic) and makes a nice clean Rev 3 machine.

Log in or register to post comments