- 21/2/22
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Hi,
as I am searching for the"best" ETA 7750, found this movement: ETA A05H21, (Hamilton H21, Mido Cal 60, Rado, Tissot) advertised like this:
"With the introduction of the Hamilton H-21 and H-31 SWATCH has stepped up their game by providing two very significant improvements to the 40-year old movement. Most obvious is the increased power reserve of 60 hours instead of 42 hours. Hamilton achieved this increase power reserve by improving the main springs on the Valjoux."
and:
"
The Hamilton H-31 and H-21 are based on the chronograph Valjoux movements 7753 and 7750. Four elements have been modified:
- The spiral has been glittered to increase accuracy and stability.
- The main spring has been improved to increase a typical power reserve of 60 hours.
- The automatic device bridge has been modified to offer decorative possibilities for personalization to the brand.
- Customized balance bridge with Hamilton H-pattern
"
It can be found on all "movement" sites and it should have the same dimensions as the 7750. BUT: found one on ebay ant the seller states: Ø30.16MM - not 30.00 . Also saw a thread on rwg.cc on saying "the case has to be slightly tweaked" for the swap from 7750 to A05H21
On top there is a version with silicon balance spring...
watchbase.com
Is anyone here who already used this movement for a swap from asian A7750? Any specific knowledge about the exact size of the movement?
Unfortunately I did not find any exact specification of the A05H21 from ETA in pdf form.
Thanks
as I am searching for the"best" ETA 7750, found this movement: ETA A05H21, (Hamilton H21, Mido Cal 60, Rado, Tissot) advertised like this:
"With the introduction of the Hamilton H-21 and H-31 SWATCH has stepped up their game by providing two very significant improvements to the 40-year old movement. Most obvious is the increased power reserve of 60 hours instead of 42 hours. Hamilton achieved this increase power reserve by improving the main springs on the Valjoux."
and:
"
The Hamilton H-31 and H-21 are based on the chronograph Valjoux movements 7753 and 7750. Four elements have been modified:
- The spiral has been glittered to increase accuracy and stability.
- The main spring has been improved to increase a typical power reserve of 60 hours.
- The automatic device bridge has been modified to offer decorative possibilities for personalization to the brand.
- Customized balance bridge with Hamilton H-pattern
"
It can be found on all "movement" sites and it should have the same dimensions as the 7750. BUT: found one on ebay ant the seller states: Ø30.16MM - not 30.00 . Also saw a thread on rwg.cc on saying "the case has to be slightly tweaked" for the swap from 7750 to A05H21
Hamilton A05H21 vs ETA 7750
Need some info as I am embarking on a franken adventure. My A7750 has been showing 1-2 issues (wouldnt start even after winding when left with zero power reserve). 1st time it came back alive was when I pushed the chronograph and the 2nd time it happened was last Monday whereby I had to knock it ...
rwg.cc
On top there is a version with silicon balance spring...
Hamilton caliber H-21 Si » WatchBase
Full details and images of the Hamilton caliber H-21 Si, including a list of all watches using this movement.
watchbase.com
Is anyone here who already used this movement for a swap from asian A7750? Any specific knowledge about the exact size of the movement?
Unfortunately I did not find any exact specification of the A05H21 from ETA in pdf form.
Thanks
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