2 mac portables to play with

[falen5]

hi folks

finally got round to having a go at my first 2 mac portables.

1 is back lit the other is the non backlit

- I have 1 original portable power supply.

took the both apart - gave them a good wash and clean - put them back together and well things started happening

-

with the backlit I got it to come on with no hard drive and no floppy - flashing disc icon and a good chime

same with the other except bearly hear the chime - caps!!

-

thing is , I kept charging 1 of the batterys and its charge has been steadily  going up

to the point I put in the hard drive and up she went - wollop!

-

cleaned both floppys and tried a boot in the backlit machine, floppy drive, no hard drive, original battery(charging for 2 days) and a 9 volt battery....... booted all the way to system 6.08  - weh hey!

-

so I have been draining the battery down, charging it back up, and the 24  year old thing is holding its charge more and more

-

today I tried it with the floppy and hard drive and the whole dam thing worked (well wouldn't boot, hard drive has system 7 and its missing the memory expansion)

-

so booted on 6.08 floppy, copied sys folder over and its fully working

-

how can the battery be working at all - its over 20 years old and its holding its charge more and more? - its right next to me running prince of Persia on nothing but battery power - for last 40 min with hard drive spinning away

-

1 thing I cant figure out.. the machine says M5126 - the backlit - but no backlight!.

-

I notice some dip switches by the power connector.. is there a way of turning on and off the back light to save power

-

do the back light circuitry die on these?

-

have to recap the older machine and build a batter for that

-

but great start for first mac portables

cheers people

 

[TheWhiteFalcon]

Batteries can regain charge capability, yes. I have an eMate battery, original (obviously not lead-acid), which holds about a 10 hour charge still.

 

[falen5]

just read that if the board has the dip switch's its the non backlit machine

well the case says m5126 , but board has dip switch's !!! - darn

is there a way to tell if the screen is backlit - should I open it up

the hard drives - 1 works ( the one in the backlit) the other does not

they both spin up, and they both have some brown grease/goo on the side of them

I opened them both up to have a look - the goo seems to be mostly on the outside. what the hell is that stuff - I see no sealing gasket...is that goo the remains of the seal?

I took off the control board of the non working drive and found loads of that goo between the pcb and the body of the drive, along with a thin layer of grey foam - the foam was rotton and goo'ed to bits - so cleaned it all out - still no sign of life from that drive

both drives appear identical so thinking of swapping control boards to see if that will make it work. on the non working drive I tried it with the cover off - platter spins up, head lock solenoid opend but head just sits there - no movement. I powered down and moved head to a different position, powered up - plater spins up, lock opens and head shoots back to previous position. I checked for 'goo' on the arms coils (between the magnets) but it all seems ok. movement seems ok,

-

if that still does not work does anyone have any info on what to do - and what to do about that brown goo -

-

cheers again folks

 

[falen5]

cheers whitefalcon - that's good news.

im looking at the battery in question - its mac portable rechargeable battery M5137. cant see a date - all is there is the serial

im amazed it has charged up - from all I read they just die

the other machines battery wont hold a charge at all - it is toast

 

[Paralel]

For lead-acid batteries it is indeed possible for them to last for decades, depending on the state they were left in.

 

[falen5]

good news parallel - im luck with this one so

-

does anybody have a link for the schematics of the portable

cant find it anywhere

 

[uniserver]

If someone would send a 5126 and 5120 to BLOB, we could have some schematics.

As well with a Color Classic.

http://www.bomarc.org

Blob (307)234-3488
Bomarc Services
PO Box 1113
Casper, WY, U.S.A. 82602

 

[falen5]

reverse -engineering!

-

you mean there are no schematics uni!!!

-

dam

 

[techknight]

Nope. I had to figure it all out myself. Fortunately I know the portable inside and out now.

 

[falen5]

ahh - cheers techknight - I was still looking.

I recapped the second machine, exactly the same as I did the first - and its working 100%

out of curiosity I removed c116 on the good board to see if it would work - and it did - that's how I tested the first board - likewise it worked , then for no reason it has not given a good chime since.

put c116 back on good board and its working fine after total rebuild with drive and floppy.

so now I have 2 recapped boards - 1 working and the other giving the same power management error

I have metered out every pin on the via and pmu chips and compared them to the working board and cant find 1 dam error

think im gonna just shelf both machines for a few months and then try again - really starting to loose the cool over here and that is not a good

way to work on vintage machines

I put up the vid of the first board recap (the one that is dead now)  for anyone that has 15 minutes of their life they want to expend. you never know you might see what mistake I made

cheers people

ps: 11 min into video - can u feel the pain!!!

 

[techknight]

But.. there is a 74hc244 just below the ASC. it can break traces there as well.

 

[falen5]

techknight - your not going to believe this ..... but I got it working-

-

I tried everything I could think of - so last try was to just wash the board again

-

20 minutes with a toothbrush, on each side,dam hot water, dry by the fire for 40 minutes - and hey presto

-

the dam thing works again

-

don't ask me - it was spotless all along, and I went over the whole board with a magnifying glass - I must of missed something

-

anyway its working perfect now - I filmed it so ill put up the vid later.

-

theres allot to be said for cleaning on these boards.

-

been working on the conner drive for last 2 hours - its dead - that brown goo!

-

ill post the vid (take out all my pathetic cursing first, my god I cant believe the language out of me)

-

nearly there

 

[techknight]

probably because water minerals got into a via that had become slightly open, reconnecting it again..

Hopefully it stays working, but if not, you got via hunting to do.

I have my connection charts I made somewhere, i updated them awhile back but I never posted it. 

 

[falen5]

yep - that sounds like the problem alright

-

its been running for last 2 hours - shut it all down for the night. If it is not working tomorrow I will at least know what  the problem is - finding it will be a different story!

-

no joy with the coner drive - 40 mb - swapped the control board with the good drive on other machine, still no joy

-

opened it - platter looks good - heads appear to be good(under magnifying glass) - spins up, head goes to a position 80% out from center and that's it no other activity from heads

-

aaahhh - enough madness for 1 day

-

weh hey!

 

[falen5]

here It is ......back to life

think a leprechaun must of got into it

 

[techknight]

I couldnt help but notice that you got a few sad mac chimes before it finally came up. 

That tells me you have a pad-to-neck or via starting to go open intermittently. 

Go through all the chip pads and vias with a magnifier and flashlight, and pick through them with a fine tooth comb. make sure your not getting a bad connection somewhere. 

 

[falen5]

hey techknight.

I have looked at every part of the board , both sides  with a magnafieing glass when it was dead. I couldn't see anything.

there is an intermittent connection somewhere - how in the name of god am I going to find it!.

on the chips ,where the leg of a chip sits on the pad , threre is a small part of the pad sticking out from under each leg. I could do a continuity test from leg to pad, or just or just follow the trace to the next solder connection - takes hours!!

-

the other day when it did not work, I got the soldering iron, filed a sharp tip on it , and touched each pin of the via and power management chips in an attempt to re-solder the connection..But I tried this before on an se30, the infamous IE8 video chip. Every leg on the chip, loads of heat, molten solder, and it STILL was not making contact on 3 of the traces. Couldn't believe how it did not make contact. I guess electrolyte is pretty good at killing solder and its properties.

The only way to be sure is a full removal of a chip, clean and re solder - that's what I rekon after the se30's IE8 nightmare. What about cooking the board in an oven at 200 C .... would that be a pure disaster techknight - ive had fairly good results with laptops in the past - actually forget I said that . im not putting any apple board in an oven - stupid idea!!

1 thing - after it came back to life I have not seen the power management error since. Now the error codes seem to be random.

-

something else I was wondering, as I was removing the board from the plastic housing and putting it back in to retest it, over and over again, was that there is allot of flexing on the portables main board each time you snap it into place. That cant be good for the connections either. You would start to get paranoid about everything..... when its not working.

-

Saying all that I tried the machine a few hours and it powered up fine first time. Just wanted to see.

-

its got to the stage that if I don't let it alone for a while  I will end up doing more damage.

-

Ive switched over to the conner drive now techknight. 1 good, 1 dead.

-

let you know how it goes

-

ps - have to ask .. what is 'pad to neck'.......I have no idea at all!

 

[falen5]

while the machine is intermitantly working I went ahead and started to look at the conner drive

-

I think its dead

-

well after this vid im 99.99% sure. But Im gonna try to take the armature out, keeping the heads apart, and remove the platter. Just have to see the underside

-

 

[falen5]

hey techknight - I just saw the video you posted about 2 weeks ago about the conner hard drive gasket failure

-

I looked for any info on the conner drive, found zip, so I messed with mine (above) ...then I see your video

-

how did I miss it-

-

how do you clean a platter - I thought if you even touch the platter it is gone

-

im thinking of taking off the platter so I can look at the underside. chances are its gonna be in the same condition as the drive in your video

-

cheers