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Silver Hawk

More On Elgin 725...

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Has anyone encountered this particular dial variation?

DSCN0607.jpg

DSCN0605.jpg

I bought this one about 15 years ago, purportedly as a prototype. It is a two-battery configuration and as you can see the case back is machined as in pictures on the previous page. The crystal fits over the bezel. Very odd. The serial number on the back of the case is S056235.

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Has anyone encountered this particular dial variation?

I bought this one about 15 years ago, purportedly as a prototype. It is a two-battery configuration and as you can see the case back is machined as in pictures on the previous page. The crystal fits over the bezel. Very odd. The serial number on the back of the case is S056235.

Never seen that one before....does look like a prototype.

Welcome to :rltb: Is that you René? :huh:

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Has anyone encountered this particular dial variation?

DSCN0607.jpg

Now! I don't usually like dials without the "hour" numbers, but that is rather nice! Very elegant and simple, yet easily read to tell the time - which is of course, what watches should be about! :yes:

But also it does look like it's been "hand drawn" by - say - an excellent draughtsman or technical artist!

(I'd buy a modern watch with this dial anytime :man_in_love: )

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Has anyone encountered this particular dial variation?

DSCN0607.jpg

I bought this one about 15 years ago, purportedly as a prototype. It is a two-battery configuration and as you can see the case back is machined as in pictures on the previous page. The crystal fits over the bezel. Very odd. The serial number on the back of the case is S056235.

It does look like a prototype of some sort. There was a picture posted earlier of the 1952 Elgin prototype which was based on their 722 movement with it's stem out of the side at the 3:00 position.

Maybe John R will confirm this, but it looks to me like you have a prototype of the Elgin 725 movement.

Thanks for posting and welcome to the forum.

:kewlpics:

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Has anyone encountered this particular dial variation?

DSCN0607.jpg

I bought this one about 15 years ago, purportedly as a prototype. It is a two-battery configuration and as you can see the case back is machined as in pictures on the previous page. The crystal fits over the bezel. Very odd. The serial number on the back of the case is S056235.

Hamiltonelectric

I would like to thank you for posting pictures of your watch and giving us the serial number of the case. Of the 14 previously known dials yours is a slight variation of one of them. The dial that I have is basically the same except it has additional lines every five minutes on the dial. If you look carefully at Hamiltonelectric’s you can see where the lines should have been. Then there's another variation of this dial which I also have in the picture.

The serial number of your case puts it at almost the very bottom of my database I only have two other cases with serial numbers lower.

Several times in this discussion I've seen the term prototype I'm curious as to whether anyone has a definition of what a prototype is? I thought once they had a model number it wasn't a prototype. But Elgin did have lots of variations. For instance the 725 movement in the photograph has a balance wheel that I doubt any of you have ever seen. It's not the same as the balance wheel on the prototype.

John

Img_5555s.jpg

Img_5561s.jpg

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For instance the 725 movement in the photograph has a balance wheel that I doubt any of you have ever seen. It's not the same as the balance wheel on the prototype.

John

Img_5561s.jpg

John,

I'm glad that you were able to share additional comments regarding the watch shown in the picture hamiltonelectric posted earlier.

The problem that I have with the Elgin Electronic watches is that there is very little information available about them. I think I have seen more photos and have read more about them in this one thread than in all previous threads combined.

Thanks for posting.

Larry

:kewlpics:

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John_R

Was there a correlation between the case serial numbers and the movement type used?

Larry

Larry

If I look at the various cases styles and their serial numbers we don't have enough samples. For instance the 2051 10k gold filled case only has only 725 movements. But whether the case has a hatch for the battery seems to be almost entirely random through the serial numbers. For the stainless steel 2552 case I have 24 serial numbers. Of those 7 have 725 movements and 8 have 910 movements. Then they appear to be randomly scattered through the serial numbers.

John

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John_R

Was there a correlation between the case serial numbers and the movement type used?

Larry

Larry

If I look at the various cases styles and their serial numbers we don't have enough samples. For instance the 2051 10k gold filled case only has only 725 movements. But whether the case has a hatch for the battery seems to be almost entirely random through the serial numbers. For the stainless steel 2552 case I have 24 serial numbers. Of those 7 have 725 movements and 8 have 910 movements. Then they appear to be randomly scattered through the serial numbers.

John

John,

You posts always leave me with more questions. "For the stainless steel 2552 case I have 24 serial numbers. Of those 7 have 725 movements and 8 have 910 movements". So what movements are in the other 9 cases? Are they empty or do they house 722 movements?

You only have serial numbers for 24 stainless steel 2552 cases? That doesn't sound like very many. How about the 10k gold filled cases. How many serial numbers do you have? Are these watches really that scarce?

Larry

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Larry

If I look at the various cases styles and their serial numbers we don't have enough samples. For instance the 2051 10k gold filled case only has only 725 movements. But whether the case has a hatch for the battery seems to be almost entirely random through the serial numbers. For the stainless steel 2552 case I have 24 serial numbers. Of those 7 have 725 movements and 8 have 910 movements. Then they appear to be randomly scattered through the serial numbers.

John

John,

Do the "8 have 910 movements" include the 6 s/steel case numbers with 910s that I sent you?

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Larry

The number 24 can be considered a large number if you're comparing it to zero. The reason why I don't know what was in the other cases is the people who gave me the serial numbers didn't tell me what was in the case. I suspect in the case of the stainless steel cased watches they probably didn't know there was a 910 so they just assumed that I would know that it was a 725 and they didn't bother to tell me.

As you think the number 24 might be considered scarce some of the other cases are more scarce. The 722 is only been found cased up in one 18k gold case and one 14k gold case. As you're keeping track there's only one 18k gold case. There is 5 of the 14k and three of these have 725 movements. Then there's a few other case styles that I have seen but they didn't come with movements and the quantities are extremely small. There is one dial that's a small square shape and only fits the prototype movement or 722 that definitely had a different case style that's never been seen. Then there's a couple of cases that can be found only in photographs.

Then for your question of just how scarce is the most commonly available Elgin 10k gold filled 2051 case. One of the nice things about this case is the serial number is on the back so some of the numbers have come from eBay. Then the rest came from other collectors and my own collection. So just how scarce it is the number 57? Then just a reminder 57 is the number of cases some of these didn't have a watch and it.

Actually I find some of these numbers quite huge considering that supposedly they were all destroyed. The very first time I heard about Elgin making a electric watch comes from a person who said he had the only one in existence. His was a salesman sample that he somehow liberated from the salesman and all the rest had been recalled by the factory and destroyed. There are several other stories like this of how they were all destroyed. So suddenly less than 100 known to exist on the entire planet suddenly looks like a big number compared to they were all destroyed.

John

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Larry

If I look at the various cases styles and their serial numbers we don't have enough samples. For instance the 2051 10k gold filled case only has only 725 movements. But whether the case has a hatch for the battery seems to be almost entirely random through the serial numbers. For the stainless steel 2552 case I have 24 serial numbers. Of those 7 have 725 movements and 8 have 910 movements. Then they appear to be randomly scattered through the serial numbers.

John

John,

Do the "8 have 910 movements" include the 6 s/steel case numbers with 910s that I sent you?

Paul

I've already added all your serial numbers to my database so yes the numbers you include yours. So if you're really asking the question of do you have the biggest collection of 910 watches on the planet unless some more come out of hiding it looks like it.

John

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Larry

If I look at the various cases styles and their serial numbers we don't have enough samples. For instance the 2051 10k gold filled case only has only 725 movements. But whether the case has a hatch for the battery seems to be almost entirely random through the serial numbers. For the stainless steel 2552 case I have 24 serial numbers. Of those 7 have 725 movements and 8 have 910 movements. Then they appear to be randomly scattered through the serial numbers.

John

John,

Do the "8 have 910 movements" include the 6 s/steel case numbers with 910s that I sent you?

Paul

I've already added all your serial numbers to my database so yes the numbers you include yours. So if you're really asking the question of do you have the biggest collection of 910 watches on the planet unless some more come out of hiding it looks like it.

John

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So if you're really asking the question of do you have the biggest collection of 910 watches on the planet unless some more come out of hiding it looks like it.

John

John, I wouldn't be so bold....oh, go on then :lol: ...

Do I have the biggest collection of 910 watches on the planet?

:D

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Then for your question of just how scarce is the most commonly available Elgin 10k gold filled 2051 case. One of the nice things about this case is the serial number is on the back so some of the numbers have come from eBay. Then the rest came from other collectors and my own collection. So just how scarce it is the number 57? Then just a reminder 57 is the number of cases some of these didn't have a watch and it.

John,

How did you obtain the information regarding other collectors' watches? Do you have a website? How many Elgin electronic do you own?

Larry

:cheers:

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Unless you're "into" very early electric watches....prepare to be bored. :lol:

Finally found some time to work on my 725 and 910 Elgin Electronics...and have been comparing the two movements. There are more differences between these two movements than I first realized, so took a few photos and I'm slowly putting a list together of the differences.

Seems I also have a hybrid; I'd love to hear John's view on this one but more of that after the first two photos.

  • Column 1: two normal 725 movements
  • Column 2: an unusual 725 (more below) and non-standard 910
  • Column 3: normal 910 movements

Elgin-725-and-910-Movements-1.jpg

Another shot of the 910 movements:

Elgin-725-and-910-Movements-2.jpg

The main differences seem to be:



  • 910 has a re-designed, lighter balance but still retains the balance horn of the 725 and the same hacking clip of the 725
  • 910 has a re-designed coil with mounting screws at each end; 725 has its two screws on the non-horn end.
  • 910 has a re-designed movement plate to support the changed mountings of the coil
  • 910 coil has a more prominent horn (similar to Lip R148)
  • 910 has two contact wires (similar to Lip R148); 725 has a single contact wire
  • 910 has a free-floating diode; 725 has the diode stuck to the coil
  • 910 has 14 jewels to the 15 of the 725
  • 910 train bridge is reduced around the right hand screw to give additional clearance for new insulated wires (red arrow below)

So on to my hybrid below. The movement in the top right is marked as a 725 and yet it has 910 features: coil, two contact wires, balance, loose diode. John thought this was due to someone changing the train bridge plate for a 725 one but on closer inspection, this 725 marked plate also has the plate reduction (see red arrow) around the right hand screw hole to give added clearance for the 910 coil wires. So is this a transitional movement between 725 and 910? :huh:

Elgin%20725%20and%20910%20Movements%204%20with%20red%20arrow.jpg

Now to get some of these movements up-and-running. Sadly, a few of the balances have broken pivots, so out of the 10 movements, probably only 6 or 7 will ever run again.

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Very cool info my friend. To think it doesn't seem that long ago we were trying to get you your first Elgin 725!

I would have to a swag and say that is most likely a transitional movement or possibly even a lab developement model.

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To think it doesn't seem that long ago we were trying to get you your first Elgin 725!

London Buses, Bill....London Buses! :D

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I got hooked again on this thread and read it right from the start through to now :yes:

Wonderful stuff. Given the age of these 725/910 movements, you have to realise that even the (very simple) electronics involved of the diode across the contacts were at the cutting edge of the time - especially the extremely small size of the diodes used. Transistors of the day were cased up in tubes around 4.5mm in diameter and up to 8mm tall. Producing a diode - sort of half a transistor really - at the small size used in these movements would have been a pretty major challenge at the time. :yes:

I have seen "ball diodes" before, but they were around maybe four or more times the size in the 725/910 movements, and ISTR they were nearly all Germanium Diodes rather than Silicon. One of the problems with Germanium is that the material can "whisker" across and short the diode out totally - the quickest diagnosis for this is just snip one leg of the diode and if the item goes, you need a new diode! :yes:

Unfortunately, after this length of time, any replacement NOS Germanium Diode may also have "whiskered", they can do this in use or in storage. Glass encased diodes are also usually Germanium with the same problems. You won't find this documented anywhere nowadays ("whiskering") it's something old time Radio Engineers like myself just knew about from long term repair work. All you can do is check forward and reverse on a meter and reject any shorts or unusuals before use. I'd hazard a guess this might be tricky on the size of diode used in the Elgin's due to the voltage from a meter maybe overloading the diode and leaving it open circuit - not easy! :yes:

Anyway thanks guys for a good read, lots to digest and ponder there!

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Very nice Paul. It's good to see those 910s again!

Once we are finished with this thread, I think we should have it pinned. There is more information here, in this single thread, regarding the history of the Elgin electronic watch than what can be found anywhere on the internet. What say you?

:rltb:

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Once we are finished with this thread, I think we should have it pinned. There is more information here, in this single thread, regarding the history of the Elgin electronic watch than what can be found anywhere on the internet. What say you?

:rltb:

I agree. I don't recall any thread on the electric forum that has had ANYWHERE near the readership as this thread. I don't have one of these watches (although I've been tempted - but I really need to stick to Hamiltons and the Landeron based watches) but it sure has been interesting reading.

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Paul, question!

What's the current consumption of one of these movements? I've had a daft idea that maybe (just maybe) the "green thing" isn't actually a cell, but might be a high capacity capacitor they were trialling as a power source - the only way to find out would be to split one down and see what's inside the "potting" compound.

If it turned out that was the case, it would make these movements very hi-tech for the day, and almost kinetic in a sense. And it might be possible to "re-charge" a green thing using a very low current over a long time period? Mind you, that might be possible for the green thing if it were a cell as well :yes:

So many things to look at with these, I wish my eyes were better to get a better look at them!

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Paul, question!

What's the current consumption of one of these movements? I've had a daft idea that maybe (just maybe) the "green thing" isn't actually a cell, but might be a high capacity capacitor they were trialling as a power source - the only way to find out would be to split one down and see what's inside the "potting" compound.

If it turned out that was the case, it would make these movements very hi-tech for the day, and almost kinetic in a sense. And it might be possible to "re-charge" a green thing using a very low current over a long time period? Mind you, that might be possible for the green thing if it were a cell as well :yes:

So many things to look at with these, I wish my eyes were better to get a better look at them!

Mel,

I don't think any of us (me, Larry, Bill) own one of these "green things"...only John I imagine. Not having one is not a problem; it's easy to get the 725s and 910s running on standard button cells.

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Paul, question!

What's the current consumption of one of these movements? I've had a daft idea that maybe (just maybe) the "green thing" isn't actually a cell, but might be a high capacity capacitor they were trialling as a power source - the only way to find out would be to split one down and see what's inside the "potting" compound.

If it turned out that was the case, it would make these movements very hi-tech for the day, and almost kinetic in a sense. And it might be possible to "re-charge" a green thing using a very low current over a long time period? Mind you, that might be possible for the green thing if it were a cell as well :yes:

So many things to look at with these, I wish my eyes were better to get a better look at them!

Answering the questions out of order regarding the "green thing". It is a battery I've attached a scanned image from a Elgin publication September 1955. The publication was describing Electronics at Elgin. You'll notice in the description they call it a indium battery. In some other patents though they make reference to mercury oxide. So I suspect they were working on several different methods to make batteries.

John

Elgin_battery.jpg

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Answering the questions out of order regarding the "green thing". It is a battery I've attached a scanned image from a Elgin publication September 1955. The publication was describing Electronics at Elgin. You'll notice in the description they call it a indium battery. In some other patents though they make reference to mercury oxide. So I suspect they were working on several different methods to make batteries.

John

Good to see you posting again John.

Talk about leading edge technology! Indium is still being used in long life batteries today.

:cowboy:

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