Powerbook 180c and friends

[tanaquil]

This seems to be my week for fishing crap out of the basement...

I uncovered a stack of PB 1xx's I had sitting in the basement, got the whole stack off ebay 15-odd years ago. As I recall, when I bought them they were all advertised as being in various stages of semi-not-working and my plan was to try to Frankenstein one good 180c out of the pile.

I am trying to get one of the two 180c's going with my one power adapter and one battery (haven't tried the other two yet - a 150 and 160, I think?). When I press the power button, I get a nice healthy bong, but then immediate shutdown. The weird thing is, sometimes it will start the bootup process, and once I even got it to boot all the way to the desktop, at which point it whined about having a low battery (of course the power adapter was plugged in) and promptly shut down again. I was hoping letting the battery sit and charge for a while would help, but I'm still getting the same behavior.

The fact that I got all the way to the desktop at least once, and to the Welcome to Mac screen a couple of times, suggests to me that the problem is not the motherboard (at least, for now). Could the problem be a bad power adapter? With the battery fully removed, I get bong/instant shutdown on both 180c's.

I see "new" batteries for a decent price on ebay, and a power adapter too, but I'm wondering if there are other problems to rule out first. 

 

[tanaquil]

ETA: I left the 180c charging over night (battery in the compartment, adapter plugged in), and this morning the computer started up and the battery holds a charge. If I remove the power adapter, it continues to run on battery power until the battery discharges (not long, less than 1/2 an hour, but I don't expect much from these old machines... my roommate's 180c barely lasted an hour on battery power when it was brand new).

If, however, I keep the power adapter plugged in and remove the battery, it shuts down within seconds.

I don't know if this helps with diagnosing which parts need to be fixed first - the power adapter, or something on the board (the battery, at least, appears to be weak but functional).

Another issue, that I can now observe since the computer is staying powered up longer: when I start the computer up from cold, there is a band across the bottom of the screen, about two inches, where the display is blanked out. The rest of the display is fine (it isn't stretched or compressed or anything) but the bottom part of the display just isn't there. If I wait a few minutes, the full display appears and works normally. If I restart warm, the band will reappear briefly at startup but disappear by the time the desktop loads, and once again the display is fine after that.

Is this a capacitor issue or a display issue? I am not sure what is meant by the "tunneling" that people mentioned in other threads.

 

[Elfen]

Like all things in life in this Mac 68K world, the machines are going to need a goo-removing wash down and a recapping, including some of the screens. Most of the major caps are at the PSU section of the board but there are a couple of leaky caps to deal with about the logic board and screen. The screen is the hardest to do, so you might have to ask for help with it but if you want to tackle it yourself, there are threads on the forum covering all three recapping subjects.

Plus the PSU itself should be recapped too.

 

[NJRoadfan]

Which AC Adapter are you using? The 180c requires a higher amperage supply, should be model M5652 rated at 3 amps. The older models used a 2 amp supply that doesn't have enough juice to power the 180c.

 

[tanaquil]

Oh, thank you for the tip re: the power supply! Traveling right now, but I will check the model number when I'm reunited with my collection.

 

[TheWhiteFalcon]

Tunneling is when the corners of the screen start darkening as its left on, and the darkness slowly spreads, until you've got only a center "tunnel" of visibility left.

 

[tanaquil]

Which AC Adapter are you using? The 180c requires a higher amperage supply, should be model M5652 rated at 3 amps. The older models used a 2 amp supply that doesn't have enough juice to power the 180c.

Belated follow-up - it turns out I do indeed have the 2 amp power supply, was probably meant to go with one of the lower-rated powerbooks in the lot. Now I know the next step is to pick up a 3 amp power supply. Thanks so much, I would never have guessed the problem.