Swiss - T < 25

[MAXI DIAL]

SWISS - T < 25

What does it mean?

Why is it on some watches and not on others?

Why isnt it on my SS/P YM while it is on

[Uncle-AJ]

It's on older watches like my 10 year old TT sub. It's denotes that tritium has been used for the luminous dials and the <25 probably means there are less than 25 whatever radio activity is measured in. Maybe becquerel?

[finance21]

Less than 25 millicuries of tritium.

[Gedanken]

Originally Posted by Uncle-AJ

It's on older watches like my 10 year old TT sub.

And JJ would tell you that you would have gotten more than 25 if it had been a TT Blue.









Actually, that explains a lot about JJ!

[TARDIS]

Originally Posted by Uncle-AJ

It's on older watches like my 10 year old TT sub. It's denotes that tritium has been used for the luminous dials and the <25 probably means there are less than 25 whatever radio activity is measured in. Maybe becquerel?

It's Millcuries under 25. In other words, extremely low radiation.

I have it written on the caseback of my H3 Tritium watch.

Steve

[Uncle-AJ]

Thanks for filling in the gaps everyone.

Originally Posted by Gedanken

And JJ would tell you that you would have gotten more than 25 if it had been a TT Blue.


Actually, that explains a lot about JJ!

It's the extra radiation that possibly gave JJ's TT sub it's blue glow.

[Gedanken]

Originally Posted by Uncle-AJ

It's the extra radiation that possibly gave JJ's TT sub it's blue glow.

Not to mention his hairdo.

[SPACE-DWELLER]

It means "Swiss T(rash) under 25 Dollars"

[finance21]

TARDIS - double check that spelling, I think it might be off by 1 letter.

[SPACE-DWELLER]

Originally Posted by TARDIS

It's Millcuries under 25. In other words, extremely low radiation.

I have it written on the caseback of my H3 Tritium watch.

Steve

It says "Extremely low radiation" on the caseback of your H3 Tritium watch?

BTW: Good thing that JJ does not have a radioactive "Blusie", because then he wouldn't have such hairy arms.

But evidently, he must have had a LOT of "T < 25" Rolex watches judging from his hair do. I guess it is a "Flipper's Decease". Look af me for example. I have had some of those "T < 25" myself:

[Uncle-AJ]

Originally Posted by Spacedweller

It says "Extremely low radiation" on the caseback of your H3 Tritium watch?

BTW: Good thing that JJ does not have a radioactive "Blusie", because then he wouldn't have such hairy arms.

But evidently, he must have had a LOT of "T < 25" Rolex watches judging from his hair do. I guess it is a "Flipper's Decease". Look af me for example. I have had some of those "T < 25" myself:

Why are you pushing that pipe into your ear?

[Incurable]

Originally Posted by TARDIS

It's Millcuries under 25. In other words, extremely low radiation.

I have it written on the caseback of my H3 Tritium watch.

Steve

Here's a cut-n-paste from a source that explains the various designations... Tardis, your H3 watch should say plain old T25 indicating is has the maximum amount of depilatory in it...

In order for timepieces to be read in the dark, a luminescent material is laid on the dial indexes and hands. Generally speaking, the emission of light is either of photoluminescent type (determined by a exciting luminous radiation) or of radioluminescent type (determined by the radioactivity of the material).

Timepieces featuring radioluminescent emission are mostly designed for very specific uses : military watches, professional divers watches, etc. In this case, the use of radioactive material is strictly defined by ISO 3157 Standard which allows only two types of radionucleides : tritium (3H) and promethium (147 Pm). It is important to specify that these radionucleides emit a radiation of low energy.

ISO 3157 Standard allows an optional marking for timepieces emitting less than a certain value. The marking may be made on the dial as follows :


deposits activated by tritium : T
deposits activated by promethium : Pm

On the other hand, timepieces with a higher value, such as divers' watches, must be marked as follows :


deposits activated by tritium : T 25
deposits activated by promethium : Pm 0,5

The indication "T Swiss made T" means that the watch is Swiss and contains a certain quantity of tritium that emits less than 227 MBq (7,5 mCi).The indication "Swiss T<25" means that the watch is Swiss and contains a certain quantity of tritium that emits less than 925 MBq (25 mCi).



Most of the Swiss watches use a light emission of photoluminescent type. Some of them bear the optional marking "L Swiss Made L" to indicate it.

My Traser has the plain T25 indicating I should be bald soon, and able to detect it in complete darkness...

[JJ Irani]

Originally Posted by Uncle-AJ

Why are you pushing that pipe into your ear?

Nice picture, Bo. And a very nice chick in the background too!!

[SPACE-DWELLER]

Originally Posted by JJ Irani

Nice picture, Bo. And a very nice chick in the background too!!

The pic was taken in the bar of "Tower Hotel" of London where I normally stay when I am in London. You get a very nice view of the "Tower Bridge" if you are lucky to get the right table

[Uncle-AJ]

Originally Posted by Spacedweller

The pic was taken in the bar of "Tower Hotel" of London where I normally stay when I am in London. You get a very nice view of the "Tower Bridge" if you are lucky to get the right table

Tell them you know me, then you are sure to get the right table.

[SPACE-DWELLER]

Originally Posted by Uncle-AJ

Tell them you know me, then you are sure to get the right table.

Nah....it's just a matter of being lucky and being there at the right time to get a nice table. But I will mention your name anyway

[mike]

Originally Posted by MAXI DIAL

SWISS - T < 25

What does it mean?

Why is it on some watches and not on others?

Why isnt it on my SS/P YM while it is on

"SWISS T<25" indicates a dial that used a mildly radioactive compound known as tritium as the exciting agent in the paint matrix of older dials.

Your dial indicates the use of less than 25 milicuries of tritium (won't penerate the dial.

The markers were made up of Tritium,phosphors (the part that glows) and the bonding agent that holds everything together (about 90% of what you see.

Tritium itself does not glow, but causes the phosphors to "glow". Tritium has a half-life of approximately 12.5 years. After that it's ability to "excite" degrades.

The use of tritium was generally outlawed on watch dials about 1998 although several manufactures Luminox, tazer, Ball, (and some gun sights) etc.... have developed a type of "gas light technology using it.

Many times on vintage pieces the tritium appears to age or "patina"--developing an ivory, cream, or brown color. Most feel this is the result of either exposure to UV rays or moisture or a combination of the two over time.
Noteworthy, as the bonding agent drys and tritium ages many older watches equipped with steel hands developed pitting or corrosion on the hand set due to the breakdown of these components. One of the reasons Rolex switched to WG hands.

[jac67]

Originally Posted by Spacedweller

It means "Swiss T(rash) under 25 Dollars"

Now THAT'S funny.

BTW, is that USD or AUD


John.

[TARDIS]

Originally Posted by finance21

TARDIS - double check that spelling, I think it might be off by 1 letter.

No mate it isn't.

[JJ Irani]

Originally Posted by Spacedweller

It means "Swiss T(rash) under 25 Dollars"

Originally Posted by jac67

Now THAT'S funny.

BTW, is that USD or AUD


John.

[TARDIS]

Originally Posted by JJ Irani

Hey JJ, hijack me with

Someone implies I can't spell here.

[SPACE-DWELLER]

Originally Posted by JJ Irani

Of course it is authentic AUD Sheep Dollars

[SPACE-DWELLER]

Originally Posted by Spacedweller

It means "Swiss T(rash) under 25 Dollars"

Originally Posted by jac67

Now THAT'S funny.

BTW, is that USD or AUD


John.

Of course it is authentic AUD Sheep Dollars