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Sigmania

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Just wondering what people have found as far as dating different pots.

There seem to be some that are easily dated and other that I can't find any codes for.

Thoughts?
 
These pots that show up on late 80s Goldstars and Breezys seem to be easy to date.

They are also used on some Burnys.

How to read Burny pot codes

Wondering if this is a clue as to production as well as dating?

71 is apparently January of 1987 pot date.

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Most often 1980s STs have pots like these and I don't see a code that would indicate a date?

Not sure who made these from 1979

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Or these from later (90s?)

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Here is an unusual one…

http://www.tokaiforum.com/viewtopic.php?f=2&t=26293&p=197165&hilit=hss#p197165

Notable features of this guitar:

5 digit serial number on a guitar with a rosewood board

HSS rout,

11-14 body code,

pot code seems to be 99.


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So it appears that these are September 1989 pots (99) in a guitar assembled in November (11) 1989?

That all fits nicely.

The confusing part is the label on the pickguard with handwritten date of 2008? That label is unlike anything I have seen on a Tokai. Looks like Western handwriting.

But the wiring looks unchanged....

Maybe the label has to do with something else?

Looks like I am possibly seeing the word "Sold" in the part of the label that is torn. This may simply be a label for a re-seller...

d513fd8bacac4c08bc0d646dac59f87a.jpg




Btw, it also has what looks like a high mass brass saddles (SS80 or DiMarzio type?).


7302005af9a11bcc2538f00f301afdc0.jpg







SN 12824

5 digit serial number, rosewood board, HSS body.

xRx4kYt.jpg



XbAPoZb.jpg



ywqFD3z.jpg



lW6noTj.jpg



0DjKHEN.jpg



4H38T3I.jpg



8EnDOZp.jpg



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Pot codes... yeah, well... it's a bit of a black art, innit? :)

I'll share what I know... or rather what I think I know. It's basically all theories in the classic scientific sense, i e interpretations that seem to work and have yet to be disproven. Proof would be credible period documentation spelling it all out, but I've yet to see that, and I doubt we'll ever see that, frankly. I mean, we don't even know who the manufacturers were in most cases.

Most of what I have is based on the guitars that interest me the most, i e Greco Fender copies. Which is a good thing, since they more or less invariably have a plaintext month and year of manufacture in their serials, giving you a solid date to compare any pot markings to.

Anyway, first up:

The "YM X" codes seems to have been first interpreted by Burny enthusiasts, as an aid to dating unserialled instruments from the 80's and 90's. It also works fine with Grecos, which have them from about 1980. The earliest I've seen in Tokais have been 1982, and they seem to be in most guitars from about 1985-86 or so.
It's on pots with embossed markings, below the kOhm number (rarely, there's what appears to be a parts number instead, I've seen 504071, 504041, 50472 and 50442 so far).
The first character is the last digit of the year, the second one is the month (1 - 0, plus N for November and D for December). A space follows, then a letter, almost always K, but P turns up infrequently and I've heard V being reported as well. The meaning of the letter is unknown. Some sources claim that P is on push-pull pots, but this is clearly incorrect, since PP-pots are technically very different, with a large switch box (like the lower part of a mini toggle switch) attached to the bottom.
You see these in various guitars from about 1980 to at least 93-94, so there's an overlap. So, for instance, a 2 for the year could mean either 1982 or '92. In practice, that's seldom a problem, most guitars have construction tells that lets you tell the decades apart.

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Late '81/early '82 Burny RLG-50. Visible codes are 18 for Aug '81 and 1N for Nov '81.


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1985 Tokai TST-50, 56 for June '85.

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Tokai PB-45, 26 for Feb 1982, with the very rare P code (and clearly no push-pull pots). This is one of the earliest instances of pots with these codes I've seen in a Tokai.

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0D for Dec 1980 in a early'81 Greco SE. The D is easily mistaken for 0.

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The "parts numbers" version of this code style. 504071 and -41 with 06 and 07 date codes in a 1990 Greco RG-950 Rickenbacker 360 copy.
 
Next date code up:

The "vertical lines" code is found in Greco Fender copies from about 1977 to 1980, and no doubt in other guitars from that period as well. Not in Tokais, however, as far as I know. Please note that I'm not really up to speed when it comes to Tokai Gibson copies, though.

This code format has the month and year reversed compare to the YM X format: the month first, then the year. The months are also given differently than in YM X, using 1 - 9 for Jan - Sept, then J, K and L for Oct - Dec ( i e the 10th through 12th letter of the alphabet).
The month and year is followed by one, two or three vertical lines, and finally a 1 or sometimes another vertical line. The final digit is always in the same position, so if the vertical lines are fewer than three, there will be one or two spaces ahead of it.

I'm not sure if there is any practical need to find an interpretation for the vertical lines, but there is one that seems to fit rather well. It has to do with a Japanese tradition of dividing months into thirds, called jun. Two ten-day jun are followed by a third that's 8, 10 or 11 eleven days long depending on the month: upper, middle and lower jun.
Like I said, it sort of fits. Would you need to subdivide date codes into periods that short for QA purposes? Well, other manufacturers don't seem to have thought so... but then again, US manufacturers often dated their pots by the week (and still do, I think?).
Who knows? It's an hypothesis at least.

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1977 Greco SE: 97 for Sept 1977, single vertical line, two spaces and a 1. Note the "parts number" above it. 7 or 4 in the penultimate position could differentiate linear and log pots, 4 is found on tone pots.

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1978 Greco SE, K8 for Nov 1978. Two vertical lines, one space and a 1. These have the plaintext kOhm and log-lin info.


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Mid-1979 Greco SE-800, one pot is February with two lines, the other March with one line. The final digit has no clear "hook" to indicate that it's a 1.


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Nov 1979 Greco SE600J. Semi-obscured, but we see the J in use for October and at least one vertical line.
 
The rubber stamp code is a fairly early one, used in Grecos from at least 1974 up until 1976 or possibly into '77, and I've personally seen them in Heerby's as well. It might have been used significantly earlier than this as well, but so far, I haven't really looked that far back much.

It's stamped, not embossed, but seems conceptually similar to the vertical lines code: it's month first then year, and it uses J, K and L for Oct-Dec. But it has no vertical lines, instead, the M and Y characters are followed by a 1, a 2 or a 3, so whatever it indicates it could be the same as the lines. The final character is an underlined letter of unknown meaning. I haven't really paid much attention to it, but I found A, B, H and I when I looked through my own pics. This format also uses part numbers and plaintext tech info interchangeably.

2022-02-10 16.49.29-1.jpg
1976 Greco PB-700. Dec '75 and Jan '76 codes and parts number stamps.

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1976 Heerby SG-480. All four pots are March '76, plaintext tech info.


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1976 Greco TE-500. Oct 1976, parts number.
 
And there are other recurring pots with markings as well. One type is the J NOBLE pots, often seen in Fernandes RST's and other Revivals, from about 1982 and into the 90's. Infuriatingly, they have markings than not only seems undeciperable but are also really hard to se. They're on the edge of the pots, not the bottom, with the interesting bits facing the solder lugs, often being obscured by cables and general clutter.

The markings say "J NOBLE" (which I assume is a brand name), then often (but not always) 15, the comes the tech info. then, just above the middle solder lug, some potentially interesting bits that makes no sense afaik: A8P, A8Y, bY, bS... it doesn't seem to connect to any obvious time-telling system. Mysterious stuff.


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It's all BS to me...

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One little oddity with Fernandes' use of the pots in Strats: they're all "long-stemmed", not your typical short Strat pots. An extra nut is used as spacer.
 
This is really great info!

It would be great if there was a way to pull all of this sort of dating reference material together and udate the registry...

Time For An Overhaul/Update Of The Registry?

I have been doing a lot of work using what you have shared in dating that first type of pots to sort out the dates of different serial number schemes in periods where the serial numbers are not date based and where there seems to be a general lack of info on Tokai STs (1983-2009).

So far that first type of pots with "YM X" I am seeing on Tokais from 1987 and 1999. I am hoping they stretch into the 90s and will help to sort that stuff out. Waiting on pictures on an interesting Goldstar and hoping it has these pots.

Do you have any idea who made the different types of pots? Particularly the first type (YM X) seen on Goldstars and Breezys in the late 80s?

Noble pots show up on LS models in the early 80s as well.

I have them in a 1981 LS100S.

IMG_6155.jpeg

IMG_6158.jpeg

Thanks so much for posting this! Great stuff!
 
And to add to your vertical lines code.

I got this loaded original pickguard for a '79 Greco SE600 I was restoring years ago.

Has the vertical lines code on the pots and a different code on the pickguard that also is 1979 I believe?

Has been years since I looked at Greco stuff, so hope that is right.

IMG_1760.JPG

PG 2 ICW.jpg
 
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Do you have any idea who made the different types of pots? Particularly the first type (YM X) seen on Goldstars and Breezys in the late 80s?

Noble pots show up on LS models in the early 80s as well.

I have them in a 1981 LS100S.

I've no idea who made the YM X, vertical lines or rubber stamp pots. Hardly surprising, a business-to-business parts suppliers wouldn't normally have any interest in communicating their brand name in a way that makes it identifiable to the end consumer. That has changed though, at least when it comes to guitars, since it became obvious that guitar owners like to tinker with their instruments. In Japanese guitars, you often see GF brand pots installed as replacements, for instance. But I think we'd need to find info from inside the business to find the suppliers of those three types, and we all know how difficult that is...

But there is Noble, of course. I've never actually searched for them before, but they were quite easy to find. It's the brand name used by Teikoku Tsushin Kogyo Co. Ltd, founded in 1944 (in the Nagano prefecture, so they were well-placed) and a global corporation these days. I guess they may have info on the codes, and being global with a partner company in the US, they might even reply... :)

Teikoku Tsushin Kogyo Co., Ltd.

Other than Noble, I've come across one more "plaintext" pot brand, Cosmos. Quite rare, so far, I've seen it in one Fresher FP-380 P-bass and two Rickenbacker 4003 copies, one a Dyna Gakki-made JooDee JRB-55 from around 1977-78, the other an unknown with a fake logo from about the same time. The Fresher's pots actually have a 2 and a 3 on the housing (1982-83 actually seems to be a likely date for the bass), the Rics just the logo with "PR-3" under it (likely a model designation, I'd say).
The company is Tokyo Cosmos Electric Co. Ltd, founded in 1957, still around and using TOCOS as a brand name these days.

Potentiometer manufacturer. Tokyo Cosmos Electric

2018-05-21 07.21.10.jpg
 
And to add to your vertical lines code.

I got this loaded original pickguard for a '79 Greco SE600 I was restoring years ago.

Has the vertical lines code on the pots and a different code on the pickguard that also is 1979 I believe?
Yeah, April '79 pots.

The stamp on the pickguard is basically a plaintext date, preceded by a digit of unknown meaning, so it's Sept 19th 1979 on this particular one. It's the same system (and stamp, judging by the font style) as used on Maxon (and Fujigen, they bought out Maxon's pickup operation at some point around 1980) humbuckers, so we can safely assume that the Strat pickguards were delivered complete with pickups and harness, So it might actually be Maxon (still extant) that knows who made this pot type.

The first digit is most often a 2, with 1 and 3 also seen pretty regularly, though usually in older guitars. In 1981-82, stamps beginning with 5 turn up as well, with a weird twist: the month and day numbers only make sense if you read them in reverse: 518072 would be 27th of August 1981, for instance. You see reverse dating info here and there all the time, and combined with a habit of suddenly using the traditional Imperial calendar randomly it can turn a simple date into seeming gibberish. 352141 could well mean 14th of December 1978, for instance, 53 being Showa 53, i e year 53 of emperor Hirohito's reign. I've have no idea if it's a considered attempt at being obscure, or just an effect of having a writing system traditionally read in vertical lines from top to bottom. I mean, left to to right or right to left, who cares? 😂
 
I just came across a post on another forum trying to date pots in a TST55L.

Dating Tokai Goldstars

Looks like this type of pot was used as early as 1984?

"54" or May 1984.

Very cool!

Screen Shot 2023-01-08 at 9.42.13 AM.png
"
 
I just came across a post on another forum trying to date pots in a TST55L.

Dating Tokai Goldstars

Looks like this type of pot was used as early as 1984?

"54" or May 1984.

I had a 1982 PB with YM X codes, I posted it above. 7okai logo (badly damaged, but still) and 6-digit (early CBS era) neck plate serial.

It's 5-6 years ago, I had it tagged PB-45MRR at the time, but looking at it again, I'm not so sure. MR wasn't a standard finish for the PB-40 at that point, so that was probably why I added 5, but as a 40, it should have a black pickguard. It's more likely a PB-50, which came in MB and MR in 1982, and it was the highest model with the three-screw tuners. Either way, the pots say 26 P, for for June 1982.

Of course, it has to be said that there is a possibility that the original pots were for some reason replaced with new YM X ones in 1992. The solder work looks neat enough, though.

But I wouldn't be all that surprised if they were original. Pots are pretty much interchangeable parts, provided they're within tolerances, regardless of who makes them, and the YM X's were in use in other brands at least as early as 1981. Maybe Tokai simply got a good deal on a small batch?

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I've gotten better at documenting stuff since I had this one... no pics of the neckplate, but I recorded the serial as 104894. No pics of the body code, sadly.
 
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I have a 1982 JB45R MR that I need to open up and photograph... You are inspiring me.

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Examples of Tokai 250k ST pots.


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Seems like these pots spanned the period of all Springys into Goldstars,

I have seen these on Tokai ST/TST/ASTs from 1978-1984 at least?

Not sure who made them.

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1978 & 1979 catalogs.

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1979 ST100

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1981 ST80 MRR


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1983 TST70 Goldstar.


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AST-56. Those pickups introduced by late 1983/1984. Used Tokai AST-56 Vintage Series Electric Guitar Sunburst

"YM X"

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(Voidoid56's image)
Then after that the "YM X" codes that I have seen on Goldstars starting in 1985.


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From Voidoid56's post above on a 1985 TST50.

I think these "YM X" pots were made until 1991or 1992?

A250KOhm
MADE IN JAPAN



2345-839a8133912a1b3e7aac03f4aee9c6cd.jpeg
(also B of course)

And then by the mid 90s we see these ones.

Value of the pot over MADE IN JAPAN (2 lines)


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(eborej's photo "Tokai Custom Edition" Guitars)


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All Caps MADE IN JAPAN No Serial Number Guitars

They seem to extend into the early 2000s at least on no serial all caps MIJ Tokais.



GF

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GF by 2009

1427-ad88aefa1675782421b26a9011854330.png
Tokai Goldstar Sound"1965 Stratocaster" 3 Tone Sunburst, Alder Body,The best Strat You'll ever Play | Reverb

And continuing on into 2014 at least

Screen Shot 2023-01-13 at 1.48.45 PM.png
2014 Tokai Goldstar Sound AST-118 S-Style Electric Guitar Ash Body Blue Burst, Japan
 
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I don't think the GF labeled pots are made by Gotoh. I originally thought they were but sent Gotoh an e-mail in 2020: and they said they don't make pots. They might be made or distributed by Hayashi Shokai, who seems to supply a lot of the other parts like knobs and switches on newer Tokai guitars, but their pots don't have the GF label. HAYASHI-SHOKAI OFFICIAL WEB SITE

Below is the e-mail I received from Gotoh.
Thanks for your inquiry.
We do not manufacture potentiometers.
Many buy from a trading company that handles our products and are probably confused.
In addition, there is a possibility that it is made by another company GOTOH Pickup that manufactures pickup.


Best regards.

G-GOTOH Co., Ltd.
Web : www.g-gotoh.com
E-mail : [email protected]
 

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