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What's the best way to replace the Mac II battery

meall

Well-known member
Hello,

My Mac II is not booting. From what I can see, one of the two 3V soldered batteries is dead. Who in hell even considered soldering batteries on a board! Anyway.

What would be the best way to repair change them? I looked on eBay, 3V batteries with holding tips are almost $40! way to expensive. I also saw a few cell battery holder that can be soldered on the board and I could install CR2032 to replace the dead battery. So far that's the better and cheaper solution I found.

Any other suggestion before I go any path?

Thanks 

 

Schmoburger

Well-known member
Options are pretty much as follows

A) Leave the batteries out... Flat PRAM wierdness doesnt really affect most 68k's of that era.

B ) Cut the existing pigtails really close to the old battery, lay somefoil or something under the area and carefully solder a normal battery to the pigtails from the old one... taking care to not apply too much heat to the battery for obvious reason.

C) Buy a cheap 1/2AA holder on eBay or where-ever and install it where the battery was. formerly suspended.

D) Solder wires to the battery pads and run to an external holder mounted outside of the case or mount one elsewhere inside the case... personally this idea doesnt appeal to me, however there are a few propenents of the the external idea by virtue of it completely nullifying the chance of battery leaks destroying boards, which I can understand. It's just too messy and hackish for me.

 
Last edited by a moderator:

MJ313

Well-known member
Check this out... maybe tt's still around.

ICbN4o3.jpg.fd126d66693a939ec1d93098f589c2e6.jpg


https://68kmla.org/forums/index.php?/topic/22866-mac-ll-battery-adapter/?p=245849

 

meall

Well-known member
Options are pretty much as follows

A) Leave the batteries out... Flat PRAM wierdness doesnt really affect most 68k's of that era.

Not sure I get this one, do you mean removing the batteries (cutting them from the board)?

The machine does not boot now, and it is likely because one battery is dead.

B ) Cut the existing pigtails really close to the old battery, lay somefoil or something under the area and carefully solder a normal battery to the pigtails from the old one... taking care to not apply too much heat to the battery for obvious reason.
normal batteries can be soldered even if they do not have soldering tips? Never tried that... But anyway, finding normal batteries that have 3V seams as complex as your third option.

C) Buy a cheap 1/2AA holder on eBay or where-ever and install it where the battery was. formerly suspended.
That was an option I was looking for. but 3V batteries are not cheap. I wonder if one could use 3.6V batteries, which is something I have enough of. 

D) Solder wires to the battery pads and run to an external holder mounted outside of the case or mount one elsewhere inside the case... personally this idea doesnt appeal to me, however there are a few propenents of the the external idea by virtue of it completely nullifying the chance of battery leaks destroying boards, which I can understand. It's just too messy and hackish for me.
Yea, agree with you, not what I'd choose first. But it could be possible to take standard AA battery size holder and put it on the HDD/floppy metal frame. Still internal, AA batteries and easily found and if they leak they will still be at a distance of the main board. 




 

meall

Well-known member
I would just snip the wires so they have long leads remaining and solder in lead type. I would not attempt to solder batteries with no leads on them, they can explode form the heat and the battery itself acts as a head sink. Not sure where you saw that price, but one quick search brings up:

http://www.ebay.com/itm/SAFT-LS14250-TAB-1-2AA-Battery-Tab-3-6V-1200mAh-Lithium-replaces-Maxell-and-more-/391184102763
Hello,

The battery link you posted is for 3.6V, the Mac II uses two 3V batteries. So back to my question in my previous reply: can I use 3.6V batteries instead? if so, I have some and can buy 1/2 AA holders for a few bucks...

 

Schmoburger

Well-known member
3.6V should be fine, but that said, I've seen the Varta brand 3V ones for under 10 bucks a unit on ebay, whicch were OEM fitment on late 80's Apple's and Mac's such as the SE and IIgs so will even look mostly factory. To my understanding, the 3V ones are actually 3.6V anyway... Somebody correct me if I'm wrong.

But yes, if the Mac II won't boot, and hasnt been recapped, I would start there... I've never come across a Mac that early that would fail to boot due to flat batteries alone. Later Powermacs, particularly the TNT and Kansas machines can do some funny things with no PRAM battery, but even they will power on and boot... they just need a little persuasion.

 

unity

Well-known member
Schmoburger - The Mac II is unique in that respect, it needs good PRAM batteries to boot. I think the same applied to the Iix and IIfx as well. They can be jumped to start. Also the early Mac II boards use solid caps that don't need replacement. Not sure if tats or ceramics.

 

Schmoburger

Well-known member
Schmoburger - The Mac II is unique in that respect, it needs good PRAM batteries to boot. I think the same applied to the Iix and IIfx as well. They can be jumped to start. Also the early Mac II boards use solid caps that don't need replacement. Not sure if tats or ceramics.
Ah well there ya go... the more you know. :) And yeh I do recall that now about the caps... I remember seeing a Mac II board some time ago and being over the moon at he fact there was not a single electrolytic in sight, and from what I recall, there is only a single electrolytic axial cap on the SE logic board as well. :) I think all the bad caps they decided not to use in the Mac II or SE must have ended up in every SE/30 ever made. lol

 

EvilCapitalist

Well-known member
Does it mean I can use 3.6V?

I'm confused about this...
You can.  I had an original II with the both of the soldered batteries dead.  Used some alligator clips on the original leads (with the original batteries in place underneath) to lead up to a new battery case with two 3.6V batteries and the machine worked just fine.

 

unity

Well-known member
ok, but I need two of them, which is $14, and then I add shipping to me in Canada, another $14, and I am close to $30! That's not really cheap... Close to the $40 set I found previously.
I was just posted a random link. There may be cheaper ones.

 

Schmoburger

Well-known member
I was just posted a random link. There may be cheaper ones.
Yep, plenty of brands available and a wide variance in price between... Varta are among the most expensive. At one point they were about the highest quality batteries you could get, however I do not beleve they are made in Germany anymore. In any case, you dont specifically need to use these... Saft is the brand of choice for many enthusiasts these days as they were an OEM supplier to Apple from the late 90's onwards, are readily available, of reasonable quality and not stupidly costly. Other brands exist that are fine within their designed lifetimes... I would probably avoid the cheapest of cheap nasty Chinese no name ones however.

 

unity

Well-known member
I am not even sure of the quality of SAFT. I have bought and use them from eBay, but they are suspect counterfiet.

 

uniserver

Well-known member
before TT's nifty pcb,  the other solutions was to use any standard 1/2 aa Lithium battery.

3v - 3.6v they are all 3.6v

desolder those batts,  get some holders

http://www.mouser.com/ProductDetail/Eagle-Plastic-Devices/12BH1-2AA-2P-GR/?qs=sGAEpiMZZMuSFBMFeRq2EX4WxdDvwgXR

12BH12AA2PGR_t.jpg.0ddfc7c57e8c9342ff32626c4c7ac525.jpg


solder those down, and pop in your batteries,

for example i like to buy my 1/2 AA's from this guy he is cheap!

http://www.ebay.com/itm/Lot-of-50x-ER14250M-3-6V-1-2-AA-Lithium-Battery-with-LED-light-/181193036942?hash=item2a2ff2548e:m:mE40pIt_MzFyNVbpOyDWi-A

s-l1600.jpg.1c7c046d4282760f823623f1a0a0d763.jpg


if you want the included PCB cool... if not,  then tell him and he will clip out and test each battery for you.

I usully buy at-least 100 at a time and he usually includes about 20 more just as a nice gesture.

but keep in mind these batteries are not really fresh... but they are NOS (new old stock).

I'v had really good luck with them,  been buying them from him for almost 2 years now.

he has like 25 thousand left.   :)

 
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