How do you use the 1675 GMT function?

[ceejay]

I have found plenty of information regarding using the GMT function on the mk2 GMT's with the independantly set GMT hand but can't find any info on the older mk1.

 

Anyone know how to use it using a DG3803B movement, which I presume mimicks the original 1675?

 

Cheers

[docthor]

The GMT hand on the 1675 is a 24h hand (on the gen). You can set the second time zone via turning the bezel

[torobravo]

You cannot find the position where to set time on the GMT hand or you don´t know its function?

[JoeyB]

On all my GMTs, 6542, 1675, 16710 and 116710, I set the 24hour GMT hand to Greenwich Mean Time (GMT)/ Coordinated Universal Time (UTC). Then turn the bezel and read the time for the zone I need from the bezel.

[ceejay]

Thanks for the replies guys, but I am confused.

 

I understand the GMT hand revolves once every 24hrs...that's a start

 

I am in the UK so I set my main hands at Greenwich Mean Time. Now just say I want to follow the time in Spain which is +1hr, how do I use the 24hr hand & bezel to achieve this?  Or have I got the wrong idea about the function of the GMT hand?

[JoeyB]

If you look at the pic in my signature you will see that the time is 10:24 P.M. local, and the 4th hand is pointing between the 3 and 4 on the bezel. That tells me it is 3:24 A.M. UTC/GMT.

For Spain, being UTC/GMT +1 you turn the bezel so that the 1 o'clock marker is at the top, or '12' position. Then read the hour that the 4th hand is pointing to on the bezel. For any of the UTC/GMT '+' hours move that number directly to the '12' position.

In this picture the bezel is set to -10 UTC/GMT, the time in Hawaii. For minus UTC/GMT you subtract from 24 (24 -10 =14, and move the 14 to the '12' position) Local time was 11:45 A.M., and it was 6:45 A.M. Hawaii time. And it was 4:45 P.M. (16:45) UTC/GMT.

[ceejay]

Thanks Joey, a perfect explanation and even I understood it!

 

Cheers.

[Nanuq]

Pfffffffft, I use mine as a compass.  Point the arrow at the Sun, then 12:00 points north.

[JoeyB]

Pfffffffft, I use mine as a compass.  Point the arrow at the Sun, then 12:00 points north.

I'd have though that everything points North up there.

It's more accurate for you than those further South as well.

The GMT/UTC 24 hour hand must be set to your local time zone. And it only works in the Northern Hemisphere, and only when Daylight Savings Time is not in effect. The further away from the equator you are the more accurate the reading will be.

[docthor]

Well...speaking of the gen-like usage of a 1675 then the only way to use it right is to set the 24h hand to the same time as the usual hour hand and move the bezel to the timezone you'd like to follow.

E.g. I live in Germany and my aunt lives in St. Paul, MN.

Since she's living 7 hours back I had to move the triangle half between 3 and 4.

If you use the 24h hand "indipendently", which is possible with the rep movements, it's pretty easy to spot that there's a rep on your wrist

The 4 digit GMTs all had the GMT hand only as a 24h hand. Well...even the 5 digit had it like this but the 12h hand can be set to a different position, which isn't possible on all 4 digit GMTs.

[panerai153]

Well...speaking of the gen-like usage of a 1675 then the only way to use it right is to set the 24h hand to the same time as the usual hour hand and move the bezel to the timezone you'd like to follow.

E.g. I live in Germany and my aunt lives in St. Paul, MN.

Since she's living 7 hours back I had to move the triangle half between 3 and 4.

If you use the 24h hand "indipendently", which is possible with the rep movements, it's pretty easy to spot that there's a rep on your wrist

The 4 digit GMTs all had the GMT hand only as a 24h hand. Well...even the 5 digit had it like this but the 12h hand can be set to a different position, which isn't possible on all 4 digit GMTs.

Not exactly, although I suppose this is splitting hairs, but I have a genuine 16750 which has the 24 hour GMT hand like the 1675. the settable hour hand didn't come into being with Rolex until the 16710. Rolex to my knowledge never had a movement that has a settable GMT hand, like most of the watches from other brands that use the ETA 2893-2 as the base movement. Like docthor said, all the rep 1675's, 6542,s have a settable GMT hand, however if you use it in that fashion, and not GMT, it will be pretty noticeable to about 100th  of 1 percent of watch wearers!! I usually have my 6542's GMT hand  set to 8 hours ahead, to track the time in Eastern Europe when my wife is over there every summer. With my 1675, I just rotate the bezel until the 8 is at the normal 12 O'clock position and read the 2nd TZ directly off the bezel.

Here is my 16750 set for the 2nd TZ 8 hours ahead of mine. Time here is almost 1230, time there is almost 2030 reading the time there off the bezel insert with the GMT hand. 

[JoeyB]

To me, it makes more sense to set and leave the GMT hand set at GMT/UTC and move the bezel for different time zones. Unscrewing and screwing the crown/tube to set puts more wear on the weaker part than using the bezel.

If the GMT hand is set to GMT/UTC how is that a 'tell'?

[panerai153]

To me, it makes more sense to set and leave the GMT hand set at GMT/UTC and move the bezel for different time zones. Unscrewing and screwing the crown/tube to set puts more wear on the weaker part than using the bezel.

If the GMT hand is set to GMT/UTC how is that a 'tell'?

joey, I believe that what he was saying was if you used the GMT adjustment and had it set to something other than GMT/UTC. it would be a tell. If you were setting for 12 hours ahead for instance the GMT hand would be way out of the normal with the hour hand. If you set it to GMT like the 1675/16750, there would be no way to tell from the position of the GMT hand, may be lots of other "tells", but the GMT position would not be one of them.

[JoeyB]

Thanks for the clarification.

[cjjoyce1]

If the GMT hand is set to GMT/UTC how is that a 'tell'?

 

Because the 1575 movement 24 hour hand is not independently settable and every gen 1675 has the 24hr hand in set in normal sync with the time - i.e. at midnight all hands are pointing at 12 and at noon the hr and min hand are up at 12 while the 24hr hand is at 6 and so forth.  Seeing a 1675 with the hands any other way either says your watch is fake or you put the hands on wrong.

 

To the OP, I have the DG movement and for whatever reason, mine does NOT have an independently settable GMT hand which is perfect in my book.  I use mine per gen - I set the watch to the local time and rotate the bezel to reflect UTC. 

[JoeyB]

Because the 1575 movement 24 hour hand is not independently settable and every gen 1675 has the 24hr hand in set in normal sync with the time - i.e. at midnight all hands are pointing at 12 and at noon the hr and min hand are up at 12 while the 24hr hand is at 6 and so forth.  Seeing a 1675 with the hands any other way either says your watch is fake or you put the hands on wrong.

So, regardless of where you are in the world, when it is midnight where you are at, and your watch is set to where you are at reading midnight, the GMT 24 hour hand is reading the very same time?

[TeeJay]

When I went to Tokyo for my honeymoon, I wore a GMT II... The main hands were set to local time, and the bezel was tracking the time in the UK. I know the GMT was created to resolve jet lag, and I don't know if anyone else has found this, but I found that being aware of the time in the other timezone, I couldn't adjust to the local time at all, and felt 'stuck' on UK time

[JoeyB]

I travel with my GMT IIc with the hour hand set to my home time (central). My GMT hand is set to GMT/UTC and I turn the bezel to the time zone I am in (GMT/UTC +or-). I read the visited time from bezel at the GMT 4th hand. It seems to work for me. I've never suffered from jet lag. And this watch has the GMT 'quickset' jumping hand.

[TeeJay]

I travel with my GMT IIc with the hour hand set to my home time (central). My GMT hand is set to GMT/UTC and I turn the bezel to the time zone I am in (GMT/UTC +or-). I read the visited time from bezel at the GMT 4th hand. It seems to work for me. I've never suffered from jet lag. And this watch has the GMT 'quickset' jumping hand.

I'm wondering if it might have been the size of the time difference, as when I've travelled within Europe, I wasn't ever affected by it, and just accepted the new time, but that really threw me for a loop... The next time I travel, my plan is to leave the main hands on UK time, rotate the bezel as required, and try reading off that

[cjjoyce1]

So, regardless of where you are in the world, when it is midnight where you are at, and your watch is set to where you are at reading midnight, the GMT 24 hour hand is reading the very same time?

Yup.

 

So you rotate the bezel to represent the 2nd time zone you want to track.  Since I'm on the East coast and we are -5hr/GMT right now, my bezel is turned so 5 is at the 12 o'clock position.  It's 14:12 right now and my 24hr hand is pointing at just past the 7 position on the dial, but just past 19 on the bezel and thus accurately representing 1912z.  If I go to Chicago, I would roll the time back an hour on the watch but also roll the bezel back so 6 was at the 12 o'clock position and thus 13:12 CST is still 1912z.

[JoeyB]

OK, but if you want the time in Hawaii, which is GMT/UTC -10, putting the 10 at the 12 o'clock position gives you midnight (12:14 in the blue area).

What do you do to get France which is +2 GMT?

[cjjoyce1]

OK, but if you want the time in Hawaii, which is GMT/UTC -10, putting the 10 at the 12 o'clock position gives you midnight (12:14 in the blue area).

What do you do to get France which is +2 GMT?

 

I think you are missing how this works.  The watch must be set to local time and the bezel rotated to the appropriate UTC conversion.

 

So.....

 

Since a picture is worth 1000 words.

 

8PM In New York

 

 

is also 3PM in Honolulu

 

 

and 2AM in Paris

 

 

and 5AM in Moscow

 

 

and 10am in Tokyo

 

 

BUT each set time shows the 24hr hand pointing at 0100Z which is correct for each (Paris isn't +2 BTW)

[panerai153]

The first thing, you have to know the time difference between your home TZ and the second one you want to track, then it's simple to set the bezel either forward or back to get the second TZ.

[JoeyB]

Thanks. Oops, Paris was GMT +2 two weeks ago.

[JoeyB]

The first thing, you have to know the time difference between your home TZ and the second one you want to track, then it's simple to set the bezel either forward or back to get the second TZ.

The way I do it now is by knowing what the GMT/UTC offset is in the time zone I want.