mac plus problems

[nahuelmarisi]

I've acquired a mac plus that seems to have some kind of screen problems. First i sometimes turn it on and it makes the startup bong but it doesn't do anything else. Most of the times it just boots normally. The menubar is also marked on the screen even when the computer is off (although I guess that could be because of usage). Also the image shows sometimes a little disturbance (although that could be caused by my monitor besides it).

Any clues? how long have i got? and most important, is the problem fixable?

 

[The Macster]

Seeing the menu bar will be because of screen burn, where it has been left on for long periods of time displaying the same thing without a screensaver being used.

 

[MacMan]

The disturbance is most likely being caused by the monitor next to it, so for piece of mind you could try moving the Plus to see if it makes a difference.

My Plus occasionally turns on with a blank screen as well, but I find that pushing the reset switch normally does the trick. It has been doing it pretty much since I got it 6 years ago, but it is still working fine (touch wood). Replacing the PRAM battery may solve the dark screen problem - it seems to have done on mine anyway. Unfortunately the 4.5V AA size batteries are no longer available so you may have to mock up an equivalent. My Plus actually has a 3V coin cell in the PRAM battery compartment, connected by fly leads, and it does the job!

 

[Mac128]

nahuelmarisi, you need to be more specific about your problems ... a little distrubance? Where and under what circumstances? If the right side of the srceen goes wavy during disk access, that's one problem. There are many many more with other symptoms.

You should try to pick yourself up a copy of Larry Pina's Macintosh Repair and Upgrade Secrets or The Dead Mac Scrolls which are must haves for anyone with an older Mac and needs to diagnose symptoms to stave off major failures with routine maintenance.

Also contrary to what MacMac says, the 4.5v PRAM battery is readily available one-clcik away at RadioShack.com which has been posted numerous times on this site. While he is right you can make your own ... but, Radio Shack is an international company with stores in Europe and you should be able to mail order one no matter where you live and I would rather have the correct thing to properly fit in my Mac if it is available for a reasonable price. I think it's time to make a STICKY out of the PRAM Battery Info.

NO WAIT: strike that ... based on how often this topic comes up on the forums, I could make a fortune by going to my local Radio Shack and buying a lot of PRAM batteries and sell them on eBay for two or three times the money plus inflated shipping!

Also, the screen problem is NOT LIKELY an adjacent monitor. But as MacMan points out, you can easily determine if in the unlikely event it is causing the problem, by moving it or the Mac.

 

[equill]

It is not impossible for one Mac monitor to affect the display of another close-by monitor. For example, I have six Macs sharing a shelf, with only just over an inch between their bezels, and four of them are Compact AIOs. A IIci's active Portrait Display next to the Colour Classic causes sync. discrepancy bands to move up the CC's display. The CC's display affects the adjacent Classic II's display in the same way, and so on. It's not a large concern because I seldom have all of the Macs active at the same time, but it is as well to be aware of the potential for interference. The remedy is greater separation.

The screen burn-in has already been mentioned to you. The only remedy, if it bothers you enough, is to replace the affected CRT. If the burn-in is confined to the menu bar, it should not affect your convenience of use of the affected Mac.

Mac128 has also pointed out that 'image shows sometimes a little disturbance' is not descriptive or specific enough to be able to offer you any advice, other than the generality that electron beams (such as that which draws the display on your SE/30's screen) can be deflected also by interfering fields and faults in the driving circuitry. The symptoms may be diagnostic if you can describe them.

de

 

[MacMan]

Also contrary to what MacMac says, the 4.5v PRAM battery is readily available one-clcik away at RadioShack.com which has been posted numerous times on this site. While he is right you can make your own ... but, Radio Shack is an international company with stores in Europe and you should be able to mail order one no matter where you live and I would rather have the correct thing to properly fit in my Mac if it is available for a reasonable price. I think it's time to make a STICKY out of the PRAM Battery Info.

You are totally right, I had completely forgotten about the RadioShack batteries. I think I'll pick up one of those myself at some point in the near future.

As for the monitor interferance - I had the same problem with my Plus when it was running next to a Performa Plus display - the picture was slightly unsteady with some distortion at the edge nearest the other monitor. After moving the Plus furthur away it was fine.

 

[slomacuser]

As for the monitor interferance - I had the same problem with my Plus when it was running next to a Performa Plus display - the picture was slightly unsteady with some distortion at the edge nearest the other monitor. After moving the Plus furthur away it was fine.

I can confirm that with similiar situation!

anyway batteries do not play a role on compact macs as I know ...

 

[nahuelmarisi]

in the case of the screen what I mean is that the screen looks like a film of a tv. Ie, when you film a tv or crt, you can see some lines going past. Well i can see very faded likes moving from the top to the botton in the same way. It's something you don't notice if you just look at the machine without closer insepection. I opened the thing up and it's really clean, no capacitors leaking.

Is there anything taht could be wrong? or could this be just normal.

 

[tomlee59]

If you're talking about retrace lines, that's usually a sign that the brightness is simply cranked up too high. Turn it down, and it should go away.

If it does not, then that indicates a more serious problem, but one step at a time...

 

[nahuelmarisi]

lowering the brightness makes the lines almost invisible, yet if you look closely they're there, just thinner. I don't know what to think about it, everything else seems fine so I guess I'll use it until it dies.

 

[Mac128]

Again, can't emphasize enough ... Larry Pina's books! and I'm sure other compact Mac self-repair as well as Tom Lee's document: http://68kmla.org/files/classicmac2.pdf

The problem could be the cut-off resistor, Try adjusting R-53 (labeled "cut-off" on the analogue board). It could also be a bad R5 needs to be replaced. This is also the likely reason you have screen burn-in as the screen was operated in an over-bright condition for too long. The first thing you should do with any new acquisition is to check all the voltages and adjust them to optimal conditions to prolong the life of the Mac.

 

[Charlieman]

Also contrary to what MacMac says, the 4.5v PRAM battery is readily available one-clcik away at RadioShack.com

Not in Europe and many other developed regions. The 4.5V compact Mac PRAM battery is prohibited in its original design for environmental reasons. However, it was used in some high end cameras that are collectable, so you can find an equivalent from some specialists.

In the UK, an equivalent is available from http://www.smallbattery.company.org.uk/ Search for a 523 -- the info pages will confirm that you have found the right one. It is quite expensive, so I would check oher battery specialists too.

 

[MacMan]

In the UK, an equivalent is available from http://www.smallbattery.company.org.uk/ Search for a 523 -- the info pages will confirm that you have found the right one. It is quite expensive, so I would check oher battery specialists too.

I like it how the description page actually says that the battery is used by the Plus, 512K and 512KE - they obviously know their stuff. It is expensive though, given the current fairly low value of Pluses.

 

[nahuelmarisi]

i don't know why a battery is so essential to use this machines. I guess that if you use it everyday loosing your settings could get annoying

 

[tomlee59]

There are several options:

1) Leave the (batteryless) Plus on 24/7. Then you only lose settings in the event of a power outage.

2) If you feel guilty about the power consumed with strategy 1), and can't/won't replace the battery, you could substitute a large capacitor for the battery. A ~1F capacitor would probably hold your settings for a week or more (although I admit that I've not actually tried this), and capacitors in that range of values seem to be relatively common these days. So, if you do use the Plus regularly, but don't want to leave it on 24/7, a batteryless solution might be acceptable (and would be more or less permanent).

3) Retrofit a three-cell mini battery pack, such as those found in many cordless phones. They seem to be widely and cheaply available.

 

[Mac128]

Tom, do you just plug the capacitor into the battery holder, soldering the leads to the +/- terminal? Thats a great idea. As nahuelmarisi points out, I use different disks with the Mac, so the only thing you really need it for is the clock. If I had a solution that would hold the settings for a week between startups, that's all I would really need.

So, Charlieman, the battery no longer seems to be sold by RadioShack either. It had been for years and I had assumed it was the environmentally free model as well since we have similar laws in the US – guess not. Evidently all the recent activity brought their attention to it and they removed it. Looks like we'll all have to use your UK source! LOL Thank you for posting it. But seriously, it doesn't seem that expensive for a battery that may well last 20 years as mine has. I assume that's one reason why Apple started putting them inside the Macs rather than making the user accessible. It also costs a manufacturer much more to make and stock a custom battery that does not have widespread use. Seems like a fair price to me under the circumstances, for the proper battery to fit properly in the Mac and won't poison the environment when disposed.

Here are several sources in the US discovered after a simple Google search (about $4 more than the RS price): http://www.lowcostbatteries.com/exell_px21-fslash-523_photo-batteries_95437_part_exell-px21-523.htm

http://www.welovemacs.com/bat3020.html

(Here for $7) http://www.batteriesinaflash.com/index.php?main_page=product_info&products_id=1546

http://item.express.ebay.com/Cameras-Photo_Film-Cameras-Film-Accessories_Film-Camera-Accessories_PX21-523-A133-A21-BATTERY-for-POLAROID-CAMERAS_W0QQitemZ7623076949QQihZ017QQptdnZFilmQ20CameraQ20AccessoriesQQddnZCamerasQ20Q26Q20PhotoQQadnZFilmQ20CamerasQ2cQ20FilmQ20Q26Q20AccessoriesQQptdiZ576QQddiZ1358QQadiZ1350QQcmdZExpressItem

($10) http://store.batteryspecialists.com/a21px.html

 

[tomlee59]

Hi Mac128,

Yes, I would connect the capacitor the way you've described (+ to +, - to -), just as if it were a battery. Just make sure that the capacitor is rated for at least 5V (5.5V is a common figure), and hopefully it will work. If you actually run this experiment, I would love to hear how long it holds settings. I am only guessing that the current draw is of the same order as a wristwatch (range of a few microamperes), so it would be nice to have some hard data instead.

 

[Scott Baret]

The monitors would have to be really close to each other for the problems to happen. I once had a Plus and an LC about two centimeters apart from each other and the screens interefered with each other, yet I currently have four Classics (one of which is colour) all a foot apart without any problems.