• Hello MLAers! We've re-enabled auto-approval for accounts. If you are still waiting on account approval, please check this thread for more information.

Replacement battery for a Mac Plus?

My Plus has no battery, and it gives the sad mac screen when I try to turn it on... I believe I read somewhere that this is because it has no battery. Does anyone know the voltage/amps rating for the battery, or where I can get a new one?

 
Alas, a missing battery doesn't cause the sad mac on a Plus. But to answer your question about the battery itself, it's a 4.5V unit. These are now getting hard to find (Radio Shack used to sell them, but I've been told that this is no longer the case). You can fashion an equivalent from the little button cell-based batteries found in cordless telephones. Many of these batteries put out 3.6V, but that seems to be enough for a Plus.

 
I've got a plus that's running well and maintaining time/date (with power off overnight) with a AA alkaline battery in the holder. Anyone else try this?

 
Well, they no longer refrence it to a Mac Plus, 128k or 512k.

They list it as a PHOTO battery. Just don't tell them that you are going to use it in a Mac! :lol:

 
Hm I wonder if there is a problem with the RAM then? I'll have to look into it... Maybe corrosion?
It could be a number of things. First replace the battery.

Disconnect everything except the mouse and keyboard. Turn on the Mac Plus and you should hear the start up chime and see the flashing question mark. If you get the sad mac face then you have a RAM/motherboard/analog board issue to figure out.

At this point I would pull the RAM SIMMS, clean the edges with a soft eraser and reset them. Reassemble and try again.

http://lowendmac.com/ram/plus.shtml

If you get the sad mac, pull the SIMMS out of Bank B (leaving 2 in Bank A) and try again (it will boot with two 256K SIMMS, 512K total).

If that doesn't help then you have to get a pair of RAM SIMMS that are known to be good.

My guess is that the RAM has come loose and a re-seat might just do the trick.

You should upgrade the Plus to 4 MB as memory is so cheap.

 
I've got a plus that's running well and maintaining time/date (with power off overnight) with a AA alkaline battery in the holder. Anyone else try this?
It seems to work (for at least some time, anyway) in many Pluses. That's a testament to the large design margins in the clock circuitry, but I wouldn't count on it for a long-term replacement. But it can work (as you've found out), and it's certainly cheap!

Btw, many editions of the Macintosh Bible mistakenly told readers that the battery was an ordinary AA cell, so many owners ended up running the same experiment that you did, only inadvertently.

 
Yes, I remember that in the Mac Bible. I almost put one in a Plus once.

I wish the batteries were better in these early Macs...I've got an almost 15 year old IBM that still works off the original clock battery, which I think is a lithium cell.

 
I've got a plus that's running well and maintaining time/date (with power off overnight) with a AA alkaline battery in the holder. Anyone else try this?
It seems to work (for at least some time, anyway) in many Pluses. That's a testament to the large design margins in the clock circuitry, but I wouldn't count on it for a long-term replacement. But it can work (as you've found out), and it's certainly cheap!
Well that's interesting to know. If a single AA cell will work, then this battery from Frys http://shop4.outpost.com/product/2977135?site=sr:SEARCH:MAIN_RSLT_PG for $6.99 should work because it puts out 3.6V. I bought one at the local Frys for $5.99 (but haven't tested it yet), so that's considerably cheaper and more convenient than mail ordering a perfect replacement for $7.99 and paying shipping too. Of course, that only helps folks with a local Frys.

I also found the this http://batterystore.com/Eveready/A21PX.htm for $7.99 which looks like the same battery which Radio Shack sells.

 
Yes, that Fry's alternative looks like it should work. It's good to know that, although Radio Shack still seems to sell the originals (thanks, Aoresteen!), there are additional choices, too.

 
If you want to avoid shipping charges just go to your local Radio Shack store and ask them to order it. Most stores will ask you to pre-pay but they will get it in a few days. That's how I have bought mine.

I also need older batteries for vintage photo flash bulb units (22v ect) and I was able to ordere them from Radio Shack stores as well.

 
Just because you got lucky regrettably does not mean that everyone will enjoy the same luck. The circuit was not designed to operate with 1.5V. Some production runs have more margin than do others, and you are one of the lucky folks who've apparently gotten one of the tolerant ones. Others have reported that an AA cell does not work for them.

As the car adverts say, "Your mileage may vary."

 
Just wanted to chime in. Got my hands on may first Plus a couple of weeks ago. No battery. I just threw in an older chargeable 1.2V AA from my camera and it works so far. This battery isn´t even fully charged. I guess before ordering, one should try anything AA in the house. If it works, one worry less!

 
Back
Top