PowerBook 170 Charger/PSU

[bunnspecial]

Hi Everyone,

I was given a PowerBook 170 today(and some other goodies like an extra battery and a charging cradle).

My issue is that the PSU seems to be dead on it. A whack on the side will sometimes get it to read in the 7.5-8V range on my VOM, but it won't stay there.

Does anyone have any ideas for where/how to look at reviving this?

Second, I know it's a standard barrel jack, and I rigged up a bench power supply to power it. My problem is that the bench supply I have is constant current, and it seems as though every time it spins up the hard drive and then tries to access it or access the floppy, the voltage will drop too low and the computer will shut off(I can see all of this on the PSU displays). Is there another off the shelf 7.5V, 2A PSU that will work with these?

Thanks.

 

[Rajel]

Bump the voltage up a bit on the bench PSU to compensate for now. The Powerbook has internal regulation that will step it down to the (probably) 5v internally that the system uses.
Up to 9V would likely be quite safe. The system may run a little warmer due to the extra voltage to the regulator, but it should still work fine.

As far as direct replacement PSUs go, the only one I can think of that runs 7.5V nowadays is the PS2 Slim power supply. Not sure about it's amperage, and you may have to replace the barrel plug with the same size the Powerbook uses.

 

[bunnspecial]

Thanks.

I pumped it up to 9V and found that I could also put the two separate PSUs in parallel, so power is now no issue(it's reliably running between 1A-1.5A with a battery installed).

It seems as though I possibly have deeper problems, though.

Usually, on a "cold" start, I get a checkerboard on the screen(although I do get a chime). A reset usually clears that.

Once I get the standard screen, I get a cursor that will move with the trackball, but the computer doesn't seem to move past there. As I said, the HDD spins up, but never sounds like it's accessing. That's really the only sign of life I get.

It DOES charge the batteries. I have two batteries, and just with a few hours plugged in both came up to about 5.5V. They both register "orange" in the charging cradle, but I was afraid to run them overnight in my bench PSU.

In the mean time, I did find a "tested and working" 140/145/170 PSU on Ebay that I ordered.

Can anyone suggest a possible explanation for what I'm seeing in the operation? I'm thinking perhaps I should pull the bottom and try reseating all the easily reseated things.

 

[Rajel]

Reseating the things can help, yeah. Also a capacitor replacement on the LCD can't hurt.
However, it does sound like your drive may be toast. These things are bloody ancient, I'm surprised that mine worked at all given that I picked it up from an outdoor stall at a flea market.
Can you boot a floppy with it? That may be able to see if the drive's working at all, or if the drive contents are just corrupt.

 

[bunnspecial]

I have a floppy that came with the computer and is marked PB170 boot disk, but the computer doesn't really seem to do anything with it either.

 

[Rajel]

Oof. The floppy might be bad as well, flaky as those are... there's no shortage of bootable floppy images you can write to a floppy nowadays though. I'd try with a fresh floppy and give one of those a shot.
Otherwise... dunno. Take it all apart, clean it up and put it back together, maybe it'll work!
Also, look out for any electrolytic capacitors in the system other than the ones in the screen or inverter board. I think most on the main boards will be ceramic which should still be good, but any electrolytics this age will have either started to dry out or leak which may require other significant board repair work.
I'd offer to take it off your hands if you can't get it running, but other than the active screen and FPU there's no benefit over my 160, especially with the 8MB RAM cap.

 

[bunnspecial]

Thanks for the help.

I'll probably try to tackle it this weekend. I did remove the bottom and reseated the RAM card, but had no change.

I really can't part with this one-it was given to me by a very dear co-worker. Her husband has alzheimers, but he was a big Mac guy and AFAIK this was his first laptop. She has given me essentially all of his old Macs as they have surfaced. He was very meticulous about keeping the accessory boxes for everything, and I'd seen the 170 box up on a shelf and asked her about it-she didn't know. I was in her office(his former office) yesterday, and happened to notice a laptop in a pile of papers

Now I'm just hoping I'll spot the 840AV . Also, given the bits and pieces I can gather, I think there MIGHT be a 128K or 512K at her house that she's promised me. She has given me a Plus, but somewhere or another along the way I picked up a both a Plus KB and a standard KB and a plastic Picasso box. Whatever the computer at home is, I think it will be something interesting.

But, with all my rambling, my point is that even if this ends up being dead, it will go in my collection as the best of the first series PBs.

And, as far as selling it-there's also the small issue of it being asset tagged . I'm okay to keep and play with it as long as I'm affiliated with my employer(which I plan to be for a long time) but otherwise it would get recycled.

One last thing-is there any way to put a laptop SCSI drive in a desktop?

 

[Rajel]

There should be pin adapters for that, most SCSI is cross-compatible. You'd just have to get an adapter that'd connect it up.
Definitely understand not being able to let it go. My 160 has quite a bit of history attached to it. Just got an email from the previous owner actually, wanting to talk about its original use and possible future for some data that I recovered from it.
Anyhoo, I'd stick with my recommendations - tear it down, clean it up, check for old electrolytic caps and if they exist, check for surrounding damage and clean the board + replace the electrolytics, and put it all back together.

 

[avadondragon]

Your original power supply is probably repairable. Most of them need a recap nowadays. I had to open mine up for a recap last year.

I have several 1xx series PowerBooks but I think the 170 is my favorite. The active matrix monochrome is SO crisp compared to the others and they seems less inclined to need recapping. However, one of my 170's has the infamous screen tunneling problem that no one has yet been able to solve. Keep an eye out for that on yours after prolonged use. BTW - the checkerboard on boot is 100% totally normal for the 170.

PowerBook SCSI drives are totally compatible with desktops but finding an adapter is going to be a pain. Sadly the 170 doesn't have SCSI disk mode like some of the other 1xx series PowerBooks. That would let you hook it up as an external SCSI disk on another Mac. A pretty nice feature that the 160 DOES have in case you ever get another Mac Rajel.

I'd say get yourself a Disk Tools boot floppy made on another machine and see if you can initialize that Hard Drive. From what you've said so far your 170 sounds like it is working fine but like is so often the case now the drive is probably shot. Sometimes they will come back to life with use. If not, there is always the PowerBook version of the SCSI2SD or CF PowerMonster II.

 

[Rajel]

Oh nice, didn't know the 160 did SCSI Target mode.
I hear the only real fix for the tunnel issue is to put the screen in a dessicant like silica gel beads for about a month (or maybe rice for longer) to absorb the moisture from the panel.

 

[bunnspecial]

Your original power supply is probably repairable. Most of them need a recap nowadays. I had to open mine up for a recap last year.

I have several 1xx series PowerBooks but I think the 170 is my favorite. The active matrix monochrome is SO crisp compared to the others and they seems less inclined to need recapping. However, one of my 170's has the infamous screen tunneling problem that no one has yet been able to solve. Keep an eye out for that on yours after prolonged use. BTW - the checkerboard on boot is 100% totally normal for the 170.

PowerBook SCSI drives are totally compatible with desktops but finding an adapter is going to be a pain. Sadly the 170 doesn't have SCSI disk mode like some of the other 1xx series PowerBooks. That would let you hook it up as an external SCSI disk on another Mac. A pretty nice feature that the 160 DOES have in case you ever get another Mac Rajel.

I'd say get yourself a Disk Tools boot floppy made on another machine and see if you can initialize that Hard Drive. From what you've said so far your 170 sounds like it is working fine but like is so often the case now the drive is probably shot. Sometimes they will come back to life with use. If not, there is always the PowerBook version of the SCSI2SD or CF PowerMonster II.

Thanks-I've noticed that it will actually tend to go away if left on its own.

As far as using another HDD/boot disk, I don't get a flashing question mark or any indication that the boot is progressing past just giving me gray screen with an active cursor.

I suppose I can pull the HDD out and try it in one of my other PBs and see if it boots.

 

[bunnspecial]

Well, I finally got around to messing with again.

It seems that the HDD is indeed dead. I pulled the cable to it, and the computer booted right up from the floppy drive. I guess it got stuck trying to boot from the HDD.

In any case, I'd hoped the HDD worked-it spins up, but I can't hear it attempting to seek.

Guess I'll be hunting down a replacement-I know that's easier said than done.

 

[bunnspecial]

Managed to find one an NOS 40mb on Ebay-$45 hurt but what are you going to do?

 

[Rajel]

Oh man, if I'd thought you were gonna look for one soon, I'd have offered the drive from my PB160 if I can get a replacement scsi2sd soon.
I got the board, but it's defective.

It's a 160MB drive too.

 

[bunnspecial]

PM me if you do decide to rid yourself of it-I have a 520c with a 133mhz PPC that would probably appreciate a drive that large. 

I sold a perfectly working Duo 210 to a friend a couple of weeks ago, and I told him that for the sake of the laptop it was probably a good thing he had it-otherwise it might have been yet another Duo with an HDD robbed from it. 

BTW, I booted it from a floppy that came with the computer, which happened to be 7.5. I suspect that's what was on the drive. The computer DOES have 8mb of RAM-should I stick with System 7 or could I get away with 7.5? 

I'm also going to try and boot it from a CD tomorrow and see if I can do anything to at least get the data off the old drive. I know it's probably gone, but I'd still like to try. 

 

[Rajel]

I think you should be able to get away with 7.5 just fine. I'm on 7.6.1 on the 160 and it doesn't take much more ram.
The RAM limitation on the 170 is what keeps me away from it, despite the superior screen. My 160's screen is still pretty damn good now that I've recapped the LCD.

 

[bunnspecial]

I've had some time to play with this some more, and I'm a bit lost.

I bought what was supposed to be an NOS 40mb Apple-branded Quantum HDD on Ebay. When I power on the computer, I can hear it spin up and seek, and then get a floppy/question mark on the screen(all expected). If I pop in the 7.0.1 Disk Utilities disk(original Apple disk, BTW), the computer will boot fine. When I launch drive set-up, though, it spends a few minutes searching the bus and then reports that it can't find any SCSI devices.

I had the same problem when I was playing with the external CD-ROM and the original HDD installed.

I'm wondering if it's possible that the SCSI bus is bad on this system. Or, barring that, could it be possible that the ribbon cable is bad?

 

[avadondragon]

Just as an experiment, plug in your external zip drive and turn on termination.  I had an SE/30 with some sort of termination problem and I stuck my zip drive on it and it would suddenly start working.  I would have thought all the internal 2.5in SCSI drives would by default have termination enabled though.  Kinda strange.  Of course at this age any hardware failure is possible so the SCSI bus could have gone bad.  

The drive DOES have the Apple logo, right?  If not, you may need the hacked version of drive tools or something 3rd party like Lido to see the drive.

 

[bunnspecial]

Thanks.

The drive has a pasted-on paper sticker with a red Apple and "40" on it-it's the same style as I've seen on other Apple drives of the era. It was sold to me as Apple OEM, and even though I don't recall seeing a Quantum 2.5" drive, it still looks and feels to me like an Apple drive.

I'll try externally terminating with the HDI-30 adapter. Unfortunately, I'm out of town this weekend, so can't get to it until Monday.