When I arrived at work I was greeted by the junior technicians who looked up to me as their senior despite just recently starting here. All in all, flexing superior experience despite only recently joining the company felt pretty nice.
It didn't take very long before a troubled junior technician approached me seeking guidance.
"Hey Dio, no matter how I try to fix this shorted power supply, nothing seems to work. I've replaced a lot of the chips, fuses, capacitors, and resistors but the short refuses to go away."
Ugh. Power supply problems are a nuisance, but seeing as the poor guy looked up to me with respect, I dutifully did my part as a respectable senior and took a look.
Inspecting the top portion of the motherboard didn't reveal much, there wasn't anything in particular that really stood out either. There didn't appear to be any corrosion near any of the components or traces, so I turned the motherboard around to the other side. The other side was just as pristine, but there was a small area with a smidge of corrosion. It was barely visible, but it was close to a hole that looked to be where a screw passed through the motherboard to hold the power supply in place and keep it secured to the chassis.
"Did you check out the corrosion by this hole?"
"There? Why would the corrosion there make a difference?"
"If the two layers on the board were shorted at some point in time then that could have been what lead to the corrosion you see there. If they are shorted, then you'll find shorts all along the power supply circuit; hence, no matter how many components you replace, you'll always have shorts."
Sure enough, when I tested for continuity between the layers on the board, the multimeter beeped confirming my suspicions that there was continuity between the layers.
"What?! I spent hours on this and you're telling me the seemingly unimportant corrosion that I ignored because it looked irrelevant was where the problem was? I was about to scrap the board... I want to cry. I want my time back. Why couldn't you just lie to me and make my life easier? Haaaah. Well... even if I know that's where the problem is, how would I fix it now?"
"Well, it depends on how bad the corrosion is, if it's spread too far into the board and it's reached the traces then it may not be possible to repair it with the tools we have available."
"What you can try to do is scrape away at the layers there and keep checking for continuity. If the continuity disappears between the layers after scraping away at the corroded area, then the power supply problem should hopefully be resolved."
Thank god it's not my problem, I don't want to do the grunt work for a job that might turn out to be a futile struggle.
"Haaaah. Thanks Dio."
After providing some pointers to my pitiful junior, I went over to my desk to check on the work orders in the system that were assigned for me to handle. Luckily, it looked like there were only three at the moment that needed my attention. I took down the bin numbers and went over to pick them all up.
The first was a gaming console with partial power, the second was a DVD player with no video and the last was a… VCR player that was eating tapes.
A freaking VCR? Are you kidding me? Why?! It's the 21st-century dude, just buy a new one for dirt cheap! What's the point in repairing it?
I was peeved about there being a VCR player so I left it aside for the time being and took a look at the gaming console first. I tested out the console and just as the memo indicated, it turned on for a moment before it immediately powered off a second later. It was a case of partial power which could turn out to be far more complicated to fix compared to a full power failure.
I took the console apart then took a look at the power supply first and tested it on a working console we had in the office. The power supply appeared to be fine, so it seemed more likely to be an issue on the motherboard. After a bit of tinkering about, I found a few faulty components, small chips, and blown fuses here and there. Luckily the main chips were fine and I didn't have to bother with them. A bit of flux, a heat gun, along with some resoldering here and there and it was as good as new.
When I opened up the DVD player, I immediately found that there was a lot of corrosion around the HDMI port. I cleaned up the corrosion with a fiberglass pen and resoldered the pins to the contacts that were loose. It was similarly a surprisingly easy fix. While I worked I was constantly interrupted by the junior repair technicians' questions. It really affected my work efficiency, but that couldn't be helped, it was the fate of the senior repair technician to provide guidance and training to his juniors.
When it was finally time to work on the VCR, my face cramped up when I took a look at it after taking it out of the box. It was the same model as the one I had at my new apartment. I instinctively had an immense aversion towards working on it; however, work was work and I couldn't be picky. I took it apart after I verified the only problem was that it ate tapes and I found a nasty brown residue staining the inner chassis. I immediately knew the VCR player definitely belonged to a smoker at some point in its long life thanks to the smell and the disgusting brown residue everywhere.
The first thing I looked at was the mode switch since I knew it was a common cause for this particular type of problem. I unscrewed the mode switch and took it apart. When I looked at the contacts, the culprit was exactly what I'd expected. The same brown residue that stained the chassis could be found on the contacts along with corrosion in a few areas as well.
I cleaned up the messy residue with isopropyl alcohol and a q tip before I took care of the corrosion that had built up on the contacts; when I finished shining it up, I applied some tune-up grease. After I reassembled the mode switch, I also cleaned up the motherboard and the chassis while I was at it before I assembled everything back together.
I hooked the VCR up to a TV and put in a blank tape in first to verify that the VCR wouldn't eat the tape up. Luckily, it worked perfectly fine so I decided to test and verify that the video was still displaying properly by putting in a VHS tape with actual recorded footage on it.
Just to be safe, I called one of the junior technicians, Rick, over and told him to test footage with me to make sure it worked fine. He had a face full of confusion, but I told him it was for educational and training purposes. I wasn't a coward or anything and I was definitely NOT afraid that a spooky ghost girl would show up. It DEFINITELY wasn't because of that.