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Harley Ronda 726


Len33

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A few months ago I spotted what I considered to be,  a rather nice looking chronograph watch for sale. On the dial, the name was, Ravisa.

Inside, the movement was a Harley Ronda 726. I bought it as non working and soon got busy, stripping it down.

There was no strap fitted, but that didn't matter for now............one thing at a time.

This watch incorporates two coils and, when checked, one of them  proved to be open circuit.

With the use of a stereo microscope, I was able to see the breaks. Yes, breaks.............both of them! Somehow, both ends had both  become disconnected.

Using my soldering iron, I was able to pick up the ends and successfully  reconnect them........which my  ohm-meter confirmed.

After that, it was cleaned and reassemble/oiled. Once done, the battery was fitted and let's see what we have.

Unfortunately, the chronograph section didn't work, but the watch did. At first, this wasn't apparent because the coil pulses for the watch section are spaced about ten seconds apart.

After thinking carefully, I could only think of one thing being responsible for the chronograph section not working...............the circuit.

Now, for some curious reason, I never checked the circuit when the watch was stripped and I had the chance to. Whenever I strip a quartz watch down, I always check the circuit to make sure that it is working.

Why, then, didn't I do so with this one? (Murphy's law!)

Well, it's my own fault and now I had to strip it down again to get at the circuit which, in this watch, is buried a few layers down and takes quite a bit of getting at.

I got  the circuit out and checked it for pulses. Yes, one section was 'pulsing' (The watch section) but the chronograph section was emitting nothing, apart

from a high pitched whine.

Damn!

After a long search, I found a firm in San Francisco ( S.T. Supply) that had the  the circuit and got busy ordering  it. 

It took about  three weeks to arrive and, once it did, I eagerly fitted it to the watch.

It's a tricky business assembling this watch, but it got done.

Right, I fitted the battery again and this time the chronograph section sprang to life................success!

Everything was working, so I left it to 'soak test' for a while.

A couple of days passed by and the watch was working  fine.

I saw a really nice, shiny S/S bracelet with black ceramic sections and immediately thought how nice that would compliment the black bezel on the watch.

The only problem was that the watch measured 19mm across the lugs and the strap was 20mm across. I couldn't find the same bracelet with 19mm and I just

had to have that bracelet.

A long story cut short, I very carefully altered the watch case and the bracelet and, voila, job done.

With its new glass and shiny bracelet, the watch looks absolutely smashing.

I just love this watch and I intend to keep it.

I wear it daily now, while giving my  mid 1960's Valjoux 72 a well earned rest.

 

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  • 2 years later...

Len33,

I just bought a watch with a Ronda 726 in it.  I liked your post!!!  It was sold as "needs a battery".  These watches can be very expensive.  From your post, you really know what you're doing.  It also appears that you have the technical equipment to repair mine......please.  By the way how do you get the stem out?  (Laughing)

Thanks,  Ken

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Hello, Ken!

Well done, for getting your hands on a Harley Ronda 726.

They are not at all easy to take apart, or to put back together again but, with a bit of luck, replacing the battery may get your watch running again.

As for removing the winding stem, I have included a rough sketch indicating the place where a thin bladed screwdriver, or whatever, needs to be inserted and pressed down, whilst pulling the stem out.

Good luck with your watch, I wish you every success.

Len.

IMG_4852.JPG

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  • 3 months later...

Hi, Ken!

Back in March, you wrote on here that you managed to get hold of a Harley Ronda 726 that  "needs a new battery."

Out of interest, did that battery replacement restore it to working condition?

Regards.

Len.

 

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