Archive for April, 2007

Guide to cleaning a PCB: How Coke nearly killed a Mac Mini

Sunday, April 29th, 2007

During Dan’s second week his Mac Mini died. He was certain that if I didn’t have reason to fire him before, that I did now. Lucky for him I was on vacation and knew nothing about what happened or even cared. When I got back we spent some time trying to figure out how, what seemed to be a normally working machine, suddenly stopped working.

Upon taking it apart (I really wish I had taken pictures) I noticed there was some familiar looking dark residue on the bottom of the case and on the board as well. Having drank tankers worth of the stuff I quickly identified what appeared to be Coke syrup. Had my favorite beverage killed this Mac Mini, or was it just a coincidence? I didn’t remember spilling anything, at least not recently. Jon had spilled some almost a year ago, but that seemed too long ago to make a difference.

I dabbed up what I could with a paper towel re-seated everything and slapped it back together. Hoping the hard drive was at fault, even though it refused to turn on at times, I was able to get it going long enough to reformat it, and bring everything up-to-date.

No more then an hour in to Dan using it, the machine shuts off again and refuses to turn on. So much for it being the hard drive. It seems like the Coke was heating up and actually bridging some of the points on the board. Assuming it probably shorted out I pronounced it dead and stuck it in a drawer.

There the Mac Mini sat for months all but forgotten until it’s hard drive was scavenged. I decided it was time to pitch the thing unless there was some way to fix it. I consulted Google, Mr. O, and Steve Marchesani. It seemed like I might be able to wash it and remove the residue which may be causing all of these problems. I still risked doing all of this to find permanent damage, but it seemed like a good idea at the time.

The Guide

Tools & Materials
– Mac Mini take-apart tools (2 thin putty knives)
– PCB cleaner spray from Radio Shack
– Distilled water from the pharmacy
– 2 cans of compressed air
– Liquid damaged circuit board (Mac Mini logic board in this case)

Step 1
Take the device completely apart. After getting the case open the Mac Mini doesn’t have too many internal components, and the only one that appeared to be affected was the logic board itself. It is important to remove anything that will come off, there is no need unnecessarily subject other things to this process. The heat sink, though technically removable didn’t seem to be worth the time, and getting it back on would have most likely ended in disaster.

Step 2
Go at the board with the PCB cleaner and complimentary brush attached to the nozzle. Over the sink seems like a good place. The cleaner appears to be something like WD40, which people said they have used to clean printed circuit boards (PCBs). I wasn’t sure how conductive WD40 is and wasn’t going to find out given the availability of a substance that clearly states that it is safe for use on a PCB. The stiff brush seems like it would break the bonds on the board, but nothing seemed harmed as I sprayed and moved the brush across the surface of the board. Not clear on where the Coke went, I drenched the board in the cleaner and scrubbed everywhere I could get at.

Step 3
Warm some distilled water in the microwave. Next do the unthinkable, drop the whole board in a shallow pool of the warm distilled water. People fill their entire computer cases with mineral oil in the name of cooling. Any other liquid doesn’t seem that harmful considering that. Distilled water, in theory, is free from any of the junk that may be found in normal drinking water. Depending on where you live or your pipes it could be anything. I did read about people putting the board under the shower, which doesn’t seem to provide any obvious benefits. Others suggested the cold cycle on the dishwasher (without any detergent), some said use the warm cycle, some even said use detergent. Though drastic, I don’t see how its much more effective, and you are likely leave deposits behind that will corrode the board over time or just make things worse. While the board is taking a bath it couldn’t hurt to use the brush from the PCB cleaner to give the board some additional surface cleaning.

Step 4
After soaking for a little rinse the board with any remaining distilled water. The bath which managed to dissolve any remaining Coke syrup is now filled with impurities, none of which you want hanging around after spending all this time.

Step 5
Proceed to use the compressed air to blow the water away. This works far better then you might suspect and gets water out of those hard to reach places like inside the DVI connector. If trapped in a small space, water may take quite a while to evaporate on it’s own. The high pressure, especially when using one of those little red straws that come with the can, forces most of the water out. If you don’t use an entire can of air then you’re probably not trying hard enough.

Step 6
Wait. Even though the board may appear dry, and it might even be, there is still the chance that water may be lurking somewhere. The Mac Mini has a little piece of foam that’s affixed to the board, which was still damp. Place the washed unit somewhere safe and with adequate ventilation, preferably where you will forget about it for a few days. I left it alone for a week which was probably more then enough.

Step 7
Check for signs of damage. Physical damage that may have occurred during the cleaning process can only lead to even more destructive things when you put it all back together and plug it in. Also check for corrosion / oxidation, if the water was clean none should be present. There also shouldn’t be signs that any liquid was present at all. If any area appears blackened its already dead and you now have a rather clean but useless board.

Step 8
Put it all back together, but only enough to make it work and not get shocked. There is no reason to go though all the trouble if it’s not going to work when fully assembled. In the case of the Mac Mini that required just about everything except for the top case. I plugged it in fully expecting the circuit breaker to pop soon after, or something to smoke. Making it that far I proceeded to push the power button. Still no smoke, and a comforting, but loud Mac Startup tone (I guess the case muffles that).

Conclusion
Much to my surprise and a few hours of testing the Mac Mini lived again. It needed a hard drive, and didn’t like a ViewSonic display unless it was using the VGA adapter, but other then that it worked normally. I even ran the graphing application with the 3D examples to sap up as much of the CPU as possible and left it on over night to simmer. It survived the night without any noted problems.

Currently the resurrected Mac Mini is spending it’s time connected to my TV serving as a pseudo Apple TV. I still don’t fully trust it. Each time I go to wake it from sleep I expect nothing to happen, but so far things have been fine.

Lesson 1: Time is worthless unless you bill for it

Sunday, April 29th, 2007

In a departure from the otherwise technical and joking nature of this site, this piece is the first in a series that will hopefully explain how we get some of the business related stuff done. As obvious and seemingly simple as they may be we’ve learned a few important and sometimes expensive lessons along the way.

Lesson 1: Time is worthless unless you bill for it

The first year with everyone under the same roof was a mess when it came to recording time. More then half our work is by hour and during a given day a it can span several different projects as well a variety of ad hoc client services.

Initially I had everyone keeping track of their own time and sending me makeshift plain-text time-sheets weekly or as needed. I was manually entering it into a program called TimeEqualsMoney by Stone Design. This wasn’t so bad back when everyone was part-time, but now with the volume and variety of work there was way too much overhead.

I had a tendency of loathing it so much that several weeks could go by before I’d actually enter all of the time sheets in and generate invoices. Faced with a growing problem and sporadic cash flow, we started to look for a solution.

At the time I decided that it needed to be networked as well Mac based so that everyone could input their own time without any unnecessary redundancy and with as little involvement from me as possible. All of us burned about a day searching before we settled on iBiz 2 by IGG Software. It was a horrible failure.

At first we thought we weren’t remembering to use the timers enough, then we thought we must not be putting in enough hours in. How could we be getting in 30 hours worth of work while spending over 60 at the office?

It was around this time I had the idea to start keeping track of everyone’s general hours in the office to try to make sense of this mess. I dabbled with the idea of creating my own system to act as in/out time log, but lack of consistent use and free time for further development killed the concept quickly.

Eventually we realized what was going on, the timer in iBiz was screwing up. We even got independent confirmation from another user saying he used a separate application to do timing for the same reason. Among the other annoyances encountered with it’s use, I had problems with time groups. Marking an invoice paid would flag an entire group, even if spanned more then one invoice. After I caught some invoices calculated incorrectly I knew it was time move on.

The search continued for another networked, Mac based, time-tracking application. We looked at iBiz’s competitor, Studiometry by Oranged Software. It appeared to have more features and the potential for greater accuracy. That was till I encountered a handful of bugs when I started testing it out. They had done a good job of hiding it, but deep inside it was a Real Basic application. While its not impossible to make a great program in Real Basic, it is however very easy to make a bad one. Given the amount of bugs Studiometry appeared to fall into the latter category.

Unwilling to sink even more money into an unknown set of problems we continued to use iBiz for a few more months, but not without checking every single thing it did by hand. Once things became accurate the recorded hours began to normalize, and subsequently so did the cash flow.

Things had gotten a little easier from when I was manually entering in everyone’s time, but the first lesson was realized. We were throwing away hours and driving ourselves crazy by not making sure time was accurately and to some degree seamlessly recorded.

To this day I’m still unsure how much money we lost due to all of the problems, but that is all behind us now. I hope this helps someone. Expect Lesson 2: You should have used QuickBooks from day 0 soon.

Don’t trust the box

Sunday, April 29th, 2007

I would have never expected the box to lie to me, but that’s exactly what happened. I purchased a Belkin Wireless G Plus MIMO (F5D9050) at BestBuy because the box had Mac logo on it and a mention of Mac OS® X 10.3.x, and 10.4.x. under the System Requirements.

When I got it home I plugged it into a Mac Mini and waited for something to happen. Nothing did. I opened the Network system preference expecting to see notification of a new device. That didn’t happen either. Despite my best judgment I decided to read the manual. Aside from a sticker on the cover it made no mention of a Mac at all. Written on the sticker was “Mac® QIG is on the CD in PDF format.” Maybe my answer would be in there.

I promptly put the CD in my computer and began to sift through the unintelligible layout. Who would ever need to look through one of these, I thought to myself. After traversing each directory I came across what appeared to be the user manual. This too wasn’t much better then the printed manual, except for mentioning “Mac OS® X v10.3.x or v10.4.x” under the System Requirements. Aside from that it was devoid of any other Mac specific reference. So much for that sticker.

Now a half hour in, I figure maybe setup isn’t even necessary and that it can be generically driven. Maybe its the Mac Mini who doesn’t like it. Next its plugged into my PowerBook which sees it in System Profiler, but won’t make any use of it.

At this point it must be broken, so I plug it into a PC just to be certain. Window XP recognizes it and prompts for the drivers. I put in the CD and Windows goes to work installing the device. A minute later a window pops up “searching for networks” and the green LED is lit.

I can only assume at this point that there must be a Mac driver on the website. Not only was there no Mac driver, but no specific Mac “QIG.” I download the manual, which though different from the one on the CD, had the same system requirements listed.

Now an hour in, I decided to call tech support, because surely some else would have noticed this by now. A few minutes later I was connected to someone in India and proceeded to tell them my predicament. After a minute or two on hold they come back to tell me that it has no Mac support. Despite going on how both the box, sticker on the manual, and system requirements all made mention of a Mac, they didn’t seem phased at all. They put me on hold again while they checked something else, or for effect. Only to come back and reiterate that there was no Mac support for the Belkin F5D9050, but an earlier (slower) model might work. Great thats just what I need, to try this all again.

The next day I went back to BestBuy and had no trouble returning it, but received no assurance that they were going to do anything about all those other boxes out there that beckon other unsuspecting Mac users. I was hoping some spark of caring, maybe even a false hope, like “we’ll contact the manufacturer” or “thanks for letting us know.” Nothing.

I hope at least someone learned something from all of this.