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Revive A Portable


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So I have this portable I picked up and the battery is of course dead. Googling around the internet for the replacement battery method, told me something interesting: that the Portable will run without a battery by using a PowerBook 100 power adapter. So I tried it. One of my 19W PowerBook 1xx adapters made a slight hum and brought up a black screen with a Sad Mac. Plugging and unplugging eventually made the Portable unresponsive. So I tried my identically labeled PowerBook 1xx Power adapter and the hard drive spun up, but the display had lines across it. Unplugging it again caused the Portable to be unresponsive. The power adapters are fine.

 

Anybody actually done this? Does it need to be plugged in longer? Should the battery be in it or not? Do I need the lower 15W or 17W adapters, or possibly the higher 24W? Is this even a reliable method of powering the Portable?

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It definitely is possible to run a Portable off a 100 series adaptor but you may get mixed results. I have safely used a 24W 165c adaptor with mine before and it seems to function just fine like that. However, I find there is a lot of difficulty in starting up with no battery installed and it often gives a Sad Mac. Fortunately in my case I managed to source a lead acid battery that fits and that coupled with a normal Portable adaptor or a 100 series adaptors seems to work fine. Maybe try yours with a 100 series adaptor and the old battery in its compartment, or possibly source a suitable replacement battery. Make sure you also have a good 9V PP3 backup battery fitted as it seems to be essential to operation.

 

A very useful thing to know is that you can often "bump start" a Portable by holding down the "reset" and "interrupt" buttons simultaneously for 10 seconds, releasing them and quickly pressing the spacebar (or any other key).

 

Unfortunately Portables seem to be flakey at best but you should hopefully get somewhere. If nothing seems to work, disconnect all power from the Portable and put it away for a few days. In my experience, that seems to cure pretty much any power problem and it will often work fine when reconnected.

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I recall reading on the interwebz a while back about somebody using an emergency light battery from Home Depot to replace the original pack in the Portable. It may be worth a trip out there with the original battery in hand to compare. Besides, unlike later Macs, Portable batteries are entirely internal so it doesn't really matter if they're 100% identical to the original battery.

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I recall reading on the interwebz a while back about somebody using an emergency light battery from Home Depot to replace the original pack in the Portable. ... unlike later Macs, Portable batteries are entirely internal so it doesn't really matter if they're 100% identical to the original battery.

Thanks, I saw this too when I was Googling, as well as several other rebuild options. I wanted to make sure the thing worked first before I ran out and started spending money on stuff I didn't need or wouldn't help.

It definitely is possible to run a Portable off a 100 series adaptor but you may get mixed results. ... Make sure you also have a good 9V PP3 backup battery fitted as it seems to be essential to operation. ... A very useful thing to know is that you can often "bump start" a Portable by holding down the "reset" and "interrupt" buttons simultaneously for 10 seconds, releasing them and quickly pressing the spacebar (or any other key).

Thanks for the heads up. Yes the "bump start" method is a VERY useful thing to know. I was inadvertently doing this during my first attempts to get it to start up. But now that I know it, it works every time. As it turns out, the Portable Control Panel settings were putting the system to sleep after about 4 minutes which is why it kept "dying" on me. When I checked never go to sleep when plugged in, it runs happily. It seems to run fine whether the battery is in it or not. But of course once I shut it down or put it to sleep, without the 9v battery, I lose everything. Will report back when I get one to see if starting up is any easier (with or without the battery).

 

My first impressions of the Portable. There is NOTHING portable about it. LOL, I would most likely use it as a desktop, therefore, unless I absolutely need a battery installed for it work reliably, I would probably opt to exclude it. The low-power Conner hard drive is the nosiest thing I have ever heard (at least mine is) – since that is even harder to replace than the battery, I would likely rely heavily upon the RAM disk. Obviously using a RAM disk means the thing needs to work perfectly so as not to lose data, which may require I get the battery in there.

 

As this is my first Portable (the original non-backlit one), I have to say I am shocked by the lack of a back-light. Apple seemingly put everything but the kitchen sink into it so people on the road would lose nothing over a desktop. But the lack of a backlight is just ridiculous. You truly do have to use it outside or with the equivalent of a bright halogen lamp hovering right over the screen in order to get close to the desktop experience. This makes really working on it just anywhere kinda impractical. I can't imagine working on it in an AirPort or an office with overhead indirect fluorescent lighting – another reason this thing isn't truly portable. The fact you can't plug it into a standard monitor output further reduces its usefulness. I was also disappointed by the fact that the pointer tends to submarine when moved quickly. Combined with a lack of backlighting this is really a problem. And I had heard so much about how great the active matrix screen was – could this be related to running it off the power adapter? Also, parts of it seem quite fragile, in particular the carrying handle – I cannot imagine putting a lot of stress on that thin plastic handle, which carrying it around a lot would do. And given that the battery had to be preserved with a lot of rules to keep it in top condition, I would have been really disappointed had I dropped $6,500 on it after a few weeks of use.

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In my experience, the Portable needs a good battery present for reliable operation, as you have found. Without the battery, it's a bit "hit and miss". You can get away with a 6v "gell cell" battery and jumper wires in a pinch, although the wires need to be fairly heavy duty. Re-celling the battery is not particularly difficult - it contains three 2.0v "Gates Cells" (now known as "Cyclon" cells, I think). Last time I re-celled my Portable's battery, I didn't have much trouble tracking a set of these down.

 

Being a lead-acid type battery, I advise taking the battery out of the Portable and storing it separately if you are putting the computer into storage for a while. This stops the computer discharging the battery, so the battery will stay in good health.

 

The 9v backup battery is only used to keep PRAM and SRAM memory alive while you swap from one main battery to another. It is mechanically switched in by a micro-switch on the battery cover. For this reason, the battery cover should always be left in place - if you leave it off, the 9v battery goes flat very quickly.

 

When considering the quality of the LCD, you must take comments in context. The quality of displays in the late 1980s was truly awful. You might think the non-backlit Portable LCD is hard to read, but compared to other displays on the market at the time, it was truly stunning. "Portable" was also a relative term. The IBM PC Portable was a massive and very heavy machine - the Mac Portable a lightweight by comparison. (Byte magazine had a picture on the cover of the original PC Portable being carried, with the floor collapsing under the user!). At the time, I had a colleague who walked to / from work every day and carried his Mac Portable. It was at least a 1 mile walk each way... carrying "a suitcase" ! When I later bought a backlit Portable, he maintained that the non-backlit LCD was superior, particularly in that it gave a much better battery life. I preferred the backlight.

 

[EDIT] Holding the reset and interrupt buttons in at the same time resets the power manager and is usually required when the Portable has just had a battery put in after being powered down completely for a while.

 

It is possible to make your own adaptor and install a different hard drive. At different stages in its long life, mine has had a standard 3.5" third height drive, a 2.5" 80GB hard drive and now a 128MB compact flash card (silent = yay). I posted a photo of this setup in this thread:

 

http://68kmla.org/forums/viewtopic.php?f=10&t=4477&p=58031&hilit=+portable#p46818

 

Beware if connecting lots of external SCSI devices; the Portable doesn't supply termination power and doesn't have a "full" SCSI terminator onboard. One other thing: at the time, the 3.5" / 1/3 height drive was revolutionary - the 3.5" 1/2 height drives were considered small at the time, so the 1/3 height drive seemed tiny and extremely high tech by comparison.

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That screen dump is a bit weird, full stop.

 

There is an alias to the System Folder on the desktop, and it does look like it is running System 7 from the menu bar. However, the dictionaries for a Microsoft app are dumped in the root directory (they should be in root of System Folder or in Extensions), and TeachText is running rather than the expected SimpleText. The icon on the blessed System Folder is the one for System 6, not System 7. What is the icon labelled Mac at the bottom of the right hand column? And what was that Threshold app at bottom lower left?

 

Without the above, expect applications to generate weird error messages whenever there is a hardware or system software refresh. The app may have checked for a combination of properties that allowed it to discriminates between a Plus and an SE, or a IIcx and an SE/30, and got its knickers in a twist. After swallowing some humble pie, the developers no doubt fixed it in the next version.

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I think that Shred has mentioned most of the important points about Portable revival but I'll add a few more.

 

The Portable external PSU is very weak, given that it would have to work against battery sulphination even when the model was new. Which is why the later PB 1xx power supply is recommended. The early models deliver 15W or 17W (I'll accept Mac128's description) and the later ones 19W plus. My notes advise against using later, more powerful supplies, owing to the low power design of the Portable's internals, but I can't find a source.

 

However, I did rejuvenate a portable battery using a ~16W supply by progressively recharging and discharging it. I trust that a summary record can be found here in the archives.

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I was rather bemused by the message myself, hence why I posted the screen grab. The setup with the files shown was how I received the machine from its previous owner, it has since been tidied up a little and I will probably re-install it at some point. It is highly likely that the machine started off with System 6 and was later upgraded to 7.1, which it is running now.

 

Threshold is a useful little application that allows you to monitor battery voltage and change the thresholds at which the System produces low power warnings. It works on the Portable and most (if not all) 68K PowerBooks.

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I remember hearing about a very similar error message on an old game that needed sound. I believe the error message was "This application can not run on the Mac XL" rather than "Lisas out! Get a Mac! ;)

 

Turned out that the author had simply written a check for the Mac's model name, and then checked if it was a Macintosh, Plus or SE. If it was none of those things then it assumed it must be a Mac XL, rather that accounting for the possibility of future models!

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Maybe these programs are designed with the thinking that Macs only have a display that runs at 512x384...both the Lisa and the Portable have displays that run at bigger resolutions, which might explain it.

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