The Lord of the Nelsonic Zelda Watches and Fixing A Bad Polarizer

When I was a kid, I desperately wanted a Nelsonic Zelda watch, but my parents were always reluctant to shell out money for toys and even if that had not been a hindrance the only ones I could ever seem to find at the store were the white or blue or pink ones.  Everyone knows the black ones are the only cool ones.

Over the years as the memory has cropped up I've occasionally checked Ebay and while there are always watches to be had, they're usually the non-black colors or else priced way too high to seem reasonable.  These things originally retailed for $20.  I kept telling myself eventually I'd find one cheaper somewhere.  Well over the years the price has crept up and not down.  Against my better judgement I decided to go ahead and buy one at the egregious price - I consoled myself with the fact that the images on the listing made the watch and the box look perfect.

Well, what I received was definitely not the item pictured in the listing.  The listing showed a brand new un-worn watch in a crease-free box.  What I received was a badly creased box that had been stored somewhere humid and a watch that was worn and scratched.  When I called the seller out, he fessed up to using "stock" photos, and in the process of deciding how to exchange the watch for one that was in better condition, I heard and lived some tales that are definitely worth re-telling.  

Going into an exchange with a seller, or any interaction with another human being when money is involved, there's always the possibility that the other party is playing you for a fool.  It's basically good bargaining ethic to try to get a better deal than the other person, and it's the best possible outcome when both parties walk away believing that they got the best of the other.  In reality one party is actually getting the lesser bargain, but as long as neither of them think it's them, it's all good.  As long as you understand this and are willing to accept the risk, you can have a little fun with it.  In this case my seller repeatedly offered to refund my payment if I wasn't happy with the process, and he seemed very transparent about the whole thing.  He was also extremely fond of referring to himself in a meaning-leaden way as a "New York Jew". 

The stock photos were the seller's own photos, but from many years ago back when he still had a stockpile of new, unused watches.  Evidently back in the 90's when the New York-based Nelsonic company went out of business, their assets were snatched up by a group of business men.  The business men who bought the company were only interested in the standard watches, not the toy/video game watches which they referred to as "the sweepings".  They offered to sell the lot to my seller and then poked fun at him afterwards speculating that he would buy anything if he would buy that junk.  Well here we are in 2021 and you practically have to pay people to take those standard Nelsonic watches, but the "sweepings" like these Zelda are approaching a market value of their own weight in gold.  My seller lamented to me that he had been too impatient to wait until now to begin selling these watches - instead he's been slowly passing a trickle of them through Ebay over the last twenty years watching the prices peak just as he reaches the end of his inventory.  He estimates that with that one photo he's sold approximately 5,000 Zelda watches, and he's certain that every watch you see in circulation has passed through his hands at one point or another.  Incidentally, out of 5,000 other sales, he tells me that I'm the first one to point out that what I received didn't match the pictures. (He even went so far as to share screenshots of some of the other messages he received from other Ebay customers praising him for the beautiful condition of the watches).

When my seller told me that he had basically reached the end, he didn't seem to be exaggerating.  I received photos of all of the boxes he had left and a pile of watches he had left.  None of it looked pristine like the photo he was using to sell them.  I picked over the boxes until I found one that looked acceptable.  When it came to the watches themselves he sent me a photo of the watch he intended to send me, and because I had never owned one, I asked why it was that the picture didn't show any of the game pieces on the screen like there were in practically every other picture I've seen of one of these watches. (I know now that it's because the watch was on "alarm" mode.).  I asked if the watch actually worked - assuming that if he had sold 5000 of them that he would know how to tell if they worked.  He told me that he didn't know how to tell that it was working and offered to send me a refund again.  I sent him a link to instructions I found online and described the process for testing to see if it worked.  The next day I received a message from him the tone of which could only be described as panic - not only did the watch not seem to be working according to the instructions, but neither did any of the other watches he had.  He described apocalyptic visions of 5000 angry customers coming back to haunt him. What's worse, after fiddling with the watch it "lost sound".  (I now know that this is because he hit the "set" button on "alarm mode" which turns off the alarm AND the game sounds.)

So not knowing if the watch was fully working I tried to make a deal with him.  He had sent me a photo of a tabletop covered in Zelda watches in various states of disrepair: some with the screens dead, some with one or both straps missing etc...  I told him to send me the watch he had picked out and one of the watch bodies he had lying on that table that I could use for spare parts and if I couldn't make one working watch out of that then it was my tough luck.  But then he asked "What if you make two working watches? What do I get out of it?"  Haha, I love this guy.  I said "You get the peace of mind of knowing that no matter what, the transaction is over and done and you get to keep your money."  He agreed, and then went off and did something else.

The next day I received a message from him that he had decided to take all his broken watches to his "watch guy".  His "watch guy" was actually a father and son operation - the elder was not interested in digital or novelty watches and would pass that work to his son - both Asian, and both apparently bitter.  But it's the good kind of bitter - the kind where if you try to make them happy they get mad at you so it's clear they find some comfort in the familiarity of the world being a place where everything sucks.  I know this is rambling but trust me when I say that you're reading the abridged version of this tale.  

His watch guy "took all his money and broken watches" and gave him back several whole watches in working condition.  He sent me pictures of two watches that he said were the best of the rest.  One of them was in markedly better physical condition than the other, but it was clear something funky was going on with the display - the LCD cells were visible but instead of being defined and black, they were faint and brown.  The other watch had prominent scratches on the face and the paint but the display looked okay.  To help me make my decision I asked him if that watch had a fresh battery in it.  Here's where, in hindsight, I think he started playing dumb a little.  He claimed that he didn't know if it had a fresh battery in it.  Fair enough.  Then I asked him to change the battery in the one with the faint display to see if that cleared the issue up - maybe the battery was just low.  He reminded me that he wasn't a technical person and he was worried that if he tried to open the watch up to change the battery that it might break somehow (his specific example was that he was worried it would lose sound) so he didn't want to do that.  Also Fair enough.  Where I think he was playing me a little was when I said that I thought that if I changed the battery out that it might clear up the screen problem - he said "Sure that could work."  I believe that he didn't technically know how fresh the battery was, and that he was afraid to open the watch up, but I'm pretty sure now he knew that a low battery wasn't the issue with the dim brown LCD cells.  Why?  Well because in the picture he sent me of the table of half-assembled watches one or two of them had every cell in the display darkened.  This is what the watch does when you first insert a battery - it's sort of a test mode to show you where the LCD is fully connected and operating correctly.  As soon as you press one of the face buttons the watch exits the test mode and shows a normal display - in fact you have to be careful not to accidentally press the face buttons when you're screwing down the battery retainer or you won't be able to see the test screen.  The only way those watches on his tabletop would be in test mode is if he had just placed a battery in them, so he was at least savvy enough to do that part.  

Of the two, I chose the watch that was in better physical condition but seemed to have some issue with the screen.  The watch arrived and I went to replace the battery, so I opened the instructions that came with the watch and read off the battery type.  Well the battery type in the instructions didn't match what I had found online, and then I realized he had sent the wrong instructions with this watch.  I had received instruction for a Super Mario World watch - this will come back into the story in a little bit.

This watch had been worked on by someone very inexpertly.  Two of the internal screws were almost completely stripped - the one for the battery retainer was particularly bad, and the coil/spring that contacts the battery holder had been pulled and twisted and bent way out of proportion - as though someone thought the watch was missing sound because the spring wasn't contacting the piezoelectric speaker on the watch back and wanted to lengthen the spring, but instead of pulling gently, gave it a yank with a pair of pliers.

I replaced the battery and was not entirely surprised when the LCD cells remained dim, brown and nearly impossible to see.  So I reached back out to the seller both to let him know that the problem was definitely not a low battery, and that he had sent me the wrong instructions.  I reminded him of our earlier agreement for him to send me a "parts" watch, and he agreed to what he affectionately called a "hostage exchange" - I send him the Super Mario World watch instructions, and he sends me the right paperwork AND the parts watch.

The parts watch I received was in unbelievably bad shape - the front cover was badly cracked, the back was missing, the clip that serves as the button contact and the positive battery terminal was missing, the negative battery contact was also missing, most of the screws were missing, and when I got it apart I found that one of the zebra connectors for the LCD was damaged beyond repair and the LCD itself had a rather visible scratch in the plastic polarizer layer.  There wasn't a lot there to use, but it still proved immensely useful.  I soldered a couple of wires to the battery terminals, cleaned up the LCD and zebra connectors as much as possible, then held the wires to a battery and sure enough part of the LCD darkened properly so I had confirmation the PCB itself was good.  I swapped in the PCB with the original watch and confirmed that the LCD cells were still faint and brown - so the problem was definitely not electronic.

In the end I did figure out how to fix the watch.  If I did not get so much fun out of fixing stuff like this I might have been disappointed in the outcome of this transaction - after all I paid a premium for a watch that was not in premium condition.  However all's well that ends well.  I learned a good deal about digital watch repair and am richer for the experience.

Fixing the Display:

A monochrome LCD display works by running an electrical charge through liquid crystals. The electrical charge causes the crystals to align - kind of like how freezing water makes it form into crystals.  When these crystals align they refract light.  However the crystal doesn't "darken" by itself.  The darkening effect is made possible by a polarization layer on the LCD that only allows light to pass through at specific angles.  When the crystals align they change the angle that the light passes through them.  When the light strikes the polarizer at the wrong angle it is stopped rather than being allowed to pass through.  The darkened areas are actually a sort of shadow.

All of the LCD cells on the watch I received were dull and brown because the polarization layer had begun to break down and was allowing too much light to pass through from the electrified cells.

Nelsonic Zelda Watch with a failed LCD polarizer

Fortunately polarizing film is a fairly common item.  Since I had never done this before there was a bit of trial and error involved.

Like most LCDs that I've messed with, the polarizer is basically a plastic adhesive sheet affixed to the front of the LCD.  I *could* have used a razor to remove the existing polarizer, but instead I opted to just place the new polarizer over top of the old one - much less to go wrong, and it doesn't really do any harm to have a second sheet on there.

My first attempt involved buying the cheapest sheet of polarizing film I could buy - mainly because I wasn't sure if that was the issue at first.  It wasn't adhesive and it warped so while it worked, the results weren't great.  I ended up buying a second sheet which was adhesive and properly flat.

I measured the viewable area of the LCD:

The next step was figuring out the proper alignment of the polarizing film.  It's simple enough, just put it over the display and rotate the sheet until the LCD cells darken.  Thankfully  To help me keep track of the orientation, I snipped the lower-right corner of the sheet before I started cutting.

I used a craft knife and a T-Square to cut the sheet to size, then failed twice trying to get it onto the LCD without specs of dust creating bubbles under the adhesive.

Third time was the charm:

Other Repair notes 

Before I knew what was wrong, I thought it was at least possible that one of the components on the watch PCB had gone bad.  However I could not find anything resembling a service manual for these watches.  I figured while I had the thing open, I'd take the components out of circuit, test them and record the measurements for posterity.  Below are some close-ups of the PCB as well as secondary diagram explaining what the components are.

• It's hard to know the voltage thresholds for the capacitors, but 10v or 16v ought to be perfectly safe.
• For some odd reason the 20 kOhm resistor is soldered on upside-down
• I didn't have a good way to measure the frequency of the oscillator
• The adjustment pot is involved with the clock crystal, but I'm not sure to what extent
• The spring is not supposed to look like that - the person I got this from, or his "watch guy" evidently likes to stretch the springs out to make sure they're getting good contact 

PCB Images

Nelsonic Zelda Watch "B" side PCB

Nelsonic Zelda Watch PCB (front side)