# Esa Dynotron 9158



## stratct (Apr 1, 2012)

I recently picked a vintage stellaris with this movement in it. This isn't my first electric watch but it is my first dynotron. I just had some questions about it

1. I heard some people talking about an index wheel, I thought is had an escapement. Can anyone clear this up?

2. What's the quality of this movement compared to other electrics such as the Hamilton electrics and such?

3. Why does it beat at 28,800 BPH but only tick 3 or 4 times a second

4. and finally, how do you like it? What would you compare it too?

Thanks all.


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## Silver Hawk (Dec 2, 2003)

1) It does have an escapement

2) Define "quality". To look at, the ESA 9150 and 9154 are much nicer looking than the 9157 and 9158....these last two movements clearly show cost-cutting measures of the mid-to-late 1970s.

3) Gearing? Many Timex electrics only tick once a second...they have an added wheel to produce this effect

4) I'd compare the 9158 with the other Dynotrons (main ones being 9150, 9154 and 9157) but also other transistorized balance wheel movements with stationary coils and moving magnets such as the Junghans 600


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