[NTLK] [OT] Mac Classic broken -- leaked caps?

anasazi4st newtonphoenix at mindspring.com
Sun Sep 20 06:21:36 EDT 2015




--Sent from one of the few non-SSL email servers left--EarthLinkHi AK:

I have a Mac Classic with a similar condition. My screen, however, is the more familiar test-pattern vertical black-and-white bars, each about an inch or so thick.

Here's a picture: http://bit.ly/1OnemFt .

It started up properly when I first got it about 10-15 years ago from a second-hand store...I didn't use it much, but every few months I would power it up to check on its status (I do this with all my vintage computers). One day the bars appeared...but after a minute or less it would start up normally. One day it refused, and the bars remained.

I DID replace all the metal can capacitors on the Classic's logic board, in answer to your question, after carefully researching their replacements--to no avail, the bars remained. I was not aware of the fix Wayne has suggested at the time, or I would have probably tried that.

I ended up getting a Mac Classic II logic board from eBay in 2008, which was almost identical...IIRC, the biggest difference was the inclusion of a microphone port and a more powerful processor.

The site EveryMac says:

"The Apple Macintosh Classic II looks nearly identical to the original Macintosh Classic that came before it, but the successor is significantly more powerful. It features a 16 MHz 68030 processor, 2 MB of RAM, and either a 40 MB or an 80 MB hard drive in a sleek, compact all-in-one case with a 9" monochrome display."

After installation, the bars still appeared at power-up...but, after about a minute, there was the familiar chime, the Happy Mac icon appeared, and it started up normally.

Unable to find a replacement video board to complete my testing, I left it go at that. From what I've read, the video card is rarely at fault for this issue--at least, that's what I read years ago. I'm kind of okay with it starting up with the vertical bars at first, although as a bit of a perfectionist I would much prefer it work as Apple intended. Perhaps one day I'll return to it and attempt a better repair, hopefully armed with another video card.

I hope this information is at least somewhat helpful to you. If I can provide any more help, please don't hesitate to post any questions. I'll be curious to know what you learn as you go forward--like, how Wayne's suggested fix works for you.

Thanks,
--Forrest


--Sent from one of the few non-SSL email servers left--EarthLink


-----Original Message-----
>From: Владислав Коротнев <vladkorotnev at gmail.com>
>Sent: Sep 20, 2015 12:52 AM
>To: newtontalk at newtontalk.net, Wayne Masek <waynemasek at rocketmail.com>
>Subject: Re: [NTLK] [OT] Mac Classic broken -- leaked caps?
>
>Hello Wayne.
>
>Thanks, I will try that.
>However don't I need to replace the caps like it used to be on old PC
>mainboards such as ePox?
>
>Thanks
>
>2015-09-20 13:29 GMT+06:00, Wayne Masek <waynemasek at rocketmail.com>:
>> Hello AK,
>> Yes I have indeed seen this precise screen in the past. From others who had
>> experienced the same disorder I was told to remove the boards from the unit,
>> apply laundry soap "magic bubbles" to the top of all of the capacitors and
>> leave it on for 3 hours. Gently wipe any excess from the tops of the
>> capacitors and dry with a light towel. If some of this residue remains spray
>> mist with warm water and gently soak up the remainder from the tops of the
>> capacitors with a paper towel and gently wipe away any excess which remains.
>> Allow to dry for 24 hours and the coat the tops of the capacitors with clear
>> nail polish. Allow another 24 hours to ensure capacitors are dry and sealed
>> with the nail polish.
>> This should resolve your problem.
>> Please let me know if this has successfully fixed the problem.
>> Regards,
>> RWM of 8BM.
>>
>>
>>
>>      On Saturday, September 19, 2015 11:34 PM, Владислав Коротнев
>> <vladkorotnev at gmail.com> wrote:
>>
>>
>>  Hello list.
>>
>> So today I needed some noncritical load for a UPS calibration, and so
>> I decided to use my Mac Classic for it.
>>
>> It's been sitting on the shelf for about a year since last boot. Back
>> in 2014 I booted it for a couple of minutes and it was constantly
>> trying to seek for a floppy (even though there was none) and sound was
>> not working.
>>
>> However today it greeted me with this: (photo)
>> http://cs625328.vk.me/v625328119/48d77/HTtd1RgDJf4.jpg
>>
>> Has anybody ever seen such a weird behavior before?
>>
>> Thanks in advance.
>> - AK.
>>
>> ----------------------------------------------------------------------
>>
>> http://newtontalk.net/



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