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Neglected Mac Classic w "video" dongle - open safely?

Posted by: ClassicMacintosh on 2024-07-24 22:04:23

Hi everyone

Have had this Classic for 20+ years but haven't really looked at it since last boot in 2005 or so - forgot it existed. Sadly, the pic is from AFTER cleaning it with distilled water. It looks bad.

Have refurbished a fair few Classics since, but am a bit confused about this one - if I take the back off, will it damage anything pulling this dongle with it? What is this dongle? It is labelled "video out" but looks like an older mac LC video connection.

There's also the piece of plastic on the back (above the power switch), but it's extremely brittle and can't seem to remove it. It says Mac Classic on the front and back. The battery and caps need to come out pronto.

Thanks in advance

Posted by: ymk on 2024-07-24 22:17:05

There must be a decent length of cable in there.

I wouldn't worry about that as much as the battery, which is likely exploded by now.

Posted by: ClassicMacintosh on 2024-07-24 23:07:14

Thanks - will give it a go and report back.

Posted by: nathall on 2024-07-26 19:00:49

The piece of plastic hides some controls for tuning the image on the CRT. You have to pop it off with a flathead by pushing the little tab on the bottom. I know on the Plus and earlier this is where the battery sits and there is an additional case screw hidden in there. I always forget about it. I don’t remember if there’s a fifth screw in there on the Classic/Classic II series.

Posted by: ClassicMacintosh on 2024-07-28 00:17:44

That certainly took longer than expected. The case was frozen in place by the battery bomb, and took hours to separate without damaging it.

Perhaps by serendipity (must've stored it laid flat, on its ... right? side) - the battery bomb appears to have popped onto the metal but spared most of the LB (edit - didn't place the battery like this - this is exactly how it was found):

Amazingly, the AB also escaped - the side is badly corroded, but the board itself is fine:

The piece of plastic hides some controls for tuning the image on the CRT. You have to pop it off with a flathead by pushing the little tab on the bottom. I know on the Plus and earlier this is where the battery sits and there is an additional case screw hidden in there. I always forget about it. I don’t remember if there’s a fifth screw in there on the Classic/Classic II series.

Couldn't find a fifth screw, that plastic tab just disintegrated at the anchor points using a guitar pick - will have to re-glue it.

Here's some more detail of the metal where the battery ended up - it's quite sticky, but also flakes in parts. Going to need a lot of work:

And finally, this was plugged into the cable sticking out back:

Posted by: cheesestraws on 2024-07-28 02:14:44

(edit - didn't place the battery like this - this is exactly how it was found)

haven't seen that before! that's the most fun battery bomb I've seen

And finally, this was plugged into the cable sticking out back:

In case you haven't already worked it out, this is mirroring the internal video out to the connector on the back - quite likely to an LCD overhead projector thingy so it could be used in a classroom or meeting room. You will probably be able to get it to work with a modern scaler type affair like an OSSC or rgb2hdmi if you want to see the screen but bigger.

Posted by: mg.man on 2024-07-28 02:20:07

And finally, this was plugged into the cable sticking out back:

A few discussions about a similar one (for 128k/512k/Plus, etc.) here :

Power R Video Adapter

I just picked up this Power R Inc. Macintosh SE video adapter, which I know Bunsen posted about earlier (but I can't seem to find it now): http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270235874553 More on the Powerr archived webpage...

68kmla.org

Compact Mac Video Adapter

Some time in 1988, a small company created a video output adapter for early compact macs with the model number 2702. There are other models, but the focus of my post is on this adapter. I can only assume they were a small company with a handful of employees because later the following year they...

tinkerdifferent.com

Posted by: Kouzui on 2024-07-28 18:46:05

Wow, that logic board is pretty lucky! I wouldn't be surprised if it works after a good cleaning and cap replacement. Sanding the rust off the chassis is a PITA but it's way better than building a reloaded board.

Also, that dongle is super cool! I have a modern version of that with the RGB2HDMI

Posted by: superjer2000 on 2024-07-29 18:47:40

for the case rust i'd pick just up some evaporust

Posted by: ClassicMacintosh on 2024-09-03 00:02:44

Thanks all. It has been indeed a pretty lucky battery bomb.

Have taken it fully apart and begun slowly removing the rust with a wire brush - it ain't fun. Here are some "before" detail pics:

It'll be sanded and wire brushed, will run some phosphoric acid over it, and then perhaps a clear coat, before moving onto the LB. Updates to follow.

Posted by: Byrd on 2024-09-03 02:58:01

I'd be looking out for a new internal frame - that's very extensive rust and sanding/brushing it'll probably fall apart in pieces.

Posted by: robin-fo on 2024-09-03 04:30:37

My Classic looked worse when I got it.. I had to sandblast and paint the chassis.

Posted by: LaPorta on 2024-09-03 04:48:55

Dunk it in evaporust for 24 hours and save yourself the headache.

Posted by: finkmac on 2024-09-03 05:11:27

evaporust + clearcoat is the way

Posted by: ClassicMacintosh on 2024-10-19 03:21:15

Update to this. Many hours of dipping & sanding later and it's pitted & macabre. However, all of the rust is gone, even though some of it was probably structural. It'll be fun to put back in and hopefully boot up safely. Will post update pics later.