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I replaced the battery in a Gucci 3000L , after replacing the watch did not work......the next step was to replace the movement, little did not know the movement 978.002 6 jewel, ETA is very hard to find, the replacement is the is the Rhonda 2 hand movement HQ751E...........after looking , and getting advice , i did not buy the replacement , i bought a circuit board, now I am stuck with a board and i need advice on how to fix the circuit board.......... There is a video by Le Arsi, he has an analyzer, is anybody familiar with this watch maker? or his analyzer? 

Here's a video

 

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Just to clarify because I'm confused?  So you have a movement that you've changed the battery it didn't work. Then you bought a new circuit board which also didn't work? So basically this means that you have one movement and two defective circuit boards?

Then  how do you know it's not a mechanical problem with the watch itself?

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 Good question JohnR, a;ways providing the circuit block was new and a worker. So as you said one movement and 2 x circuit blocks of questionable operation, the movement may as stated be faulty also so at the moment we are in an impasse where we cant verify anthing.   As regards the Le Arsi analysers I have both of them and they are good tools but a bit expensive as a one off to fix one watch.

Le Arsi is a master watch and Clock maker in the Philipines and runs a horological training school he has connections with America and is recognised there for his work.

 

 

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Thanks, where do u purchase the analyser, from Le Arsi.... How expensive are you talking about? well I have one circuit board and the watch did work...... now i have a circuit board that needs fixing.... the problem was not mechanical.......... I like to investigate things, saw the analyser on You tube and thought maybe I could use this machine...... Therefore again how expensive is this machine? 

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Hi   The ronda 751E replaces the eta978.002 and the eta 578.004. although the dial feet may need to be cut off and dial dots used.

The Le Arsi      1168-1NC86  Analyser tester with Led array and audio  cost me 1 year ago the sum of £150       The COL118 tester has no Audio and a led which is used to test the block and the coil. I have had that one for about 3 years and the cost then was around £70.   Contact him on [email protected] regarding prices.  he makes each individual Analyser to order.  look up le arsi watch analyser on google for a full history of the man and his affiliation to i think it was the AWCI. 
in the States.

So what is the situation now ?  a working watch and 1 Duff circuit  or are we still at a watch and 2 Duff circuits.

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I went looking for something else related to the watch and found the link below. Normally replacement movement arts always exactly the same but it looks like this movement was meant to be an exact replacement. As long as the dial feeder in the right place in the thickness is right that should fit the case and if it said it was made to be an exact replacement what have you got to lose.

How do you know if the problem is not mechanical?

 

https://www.esslinger.com/harley-ronda-2-hand-quartz-watch-movement-hq751e-hq978-o-a-3-7mm-to-replace-eta-978-002-and-eta-578-004/

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Some 2 hand movements only receive a pulse to the coil once every 20 seconds. 20 seconds is a very long time when you are waiting for it.

I learnt this the hard way when I bought a higher end replacement movement for a vintage quartz. Paid $250 for it. And the new movement didn't seem to work when I put it on my Chinese made pulse tester.

It was only when I passed this repair to my mentor did he tell me that both the original and new movement are working. :D

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this is what i did:

1.   Installed a new battery, put the watch on my tester did not get a pulse, waited 30 secs did not get a beep

2.  Ask my instructor what did he think I should do. He responded by telling me to buy a new movement

3.  Therefore I had already purchased  the circuit board...........replaced the circuit board 

4. The watch works!

I know this not the way to do this but i took a gamble; now i have a circuit board that needs to tested to see if its good , therefore if this happens again i well know how  to test a circuit to see if the coil is bad or some other problem.... How can this be done..........

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 Hi The le Arsi will test the board off the watch. Watch his video on this procedure. Other wise with an analogue meter you can check the board to some extent on the watch, ie   pulses  crystal and the coil if the block is faulty they are epoxy sealed and not repairable.

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5 hours ago, watchweasol said:

Hi The le Arsi will test the board off the watch. Watch his video on this procedure. Other wise with an analogue meter you can check the board to some extent on the watch, ie   pulses  crystal and the coil if the block is faulty they are epoxy sealed and not repairable.

It's amazing what you can do with basic electronic test equipment. For instance I use a $20 digital volt ohm meter to check coil resistance. Or battery voltage can be checked I'm not usually concerned about doing battery voltage with load testing.

To understand quartz watch testing I've attached a file and a couple of links. The first link is here because I wanted to see a picture of the watch you're working on. You'll notice that conveniently test points have been marked which is more common to find on Swiss watches.

The second link talks about quartz watch theory and a test procedure which I recommend a minor deviation from. The attached file unfortunately is not your watch but similar physical size.

In the attached PDF the first test is checking the battery voltage with the battery in the watch. That is the variation from the witschi's removing the battery and checking it. It's always best if you can check that powers actually getting to the circuit board versus checking the battery out of the watch. 

One test it's missing is checking for impulses because on this particular watch you can't get to the coil leads from the outside. If you can actually get to where the coil leads are an analog meter works really well much better than a digital. I like an analog meter because when it receives the impulse the needle will switch one direction or the other depending upon the polarity. Where digital meters just tend to jump because the pulses too short.

Then for the rest the testing in a little more complicated perhaps. Measure current consumption you need a really sensitive meter typically today everybody is using digital because it's hard to get really sensitive analog meters. Not that they didn't exist At one time Bulova had a really nice meter citizen and Seiko had meters. But finding an analog meter they can read a fraction of a micro amp is challenging today. Then it be really nice to the variable voltage power supply to complete the rest of the tests. You could use the watch battery for at least the current consumption test.

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&ETA-ESA_978_002

 

http://www.witschi.com/assets/files/sheets/Knowledge Quartz Watch.pdf

ETA_ETA 976.001.pdf

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Hi  It is possible to build a tester using simple electronics. I build one from drawings by Mike Catt It is buil on vero board or strip board (basically the same) and a few components. With this unit you have a variable power supply voltage display and a current consumption element as well.  You need to attach a meter for the current out put.   If Ican locate the web site again I will point you in the direction of it.

The witschi document JohnR supplied is well worth a read if you want to understand quartz watch technology.

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Hi   The white tester is the Martin Catt build,  The one with the meter attached is from Th AWCI  and the other is a mini scope all got for less than £30  apiece the scope comes as a self build kit the other two  are again assembled from others plans/drawings so food for thought.    cheers 

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I used to have a problem repairing quartz watches. Just wiping off the battery juice (electrolyte), cleaning the battery contacts, putting in a new battery and praying that the second hand moves is not good enough. You could have a shorted coil or mechanical problems that result in higher current consumption. This is why sometimes a watch with a new battery only runs for a few months.

You really need to measure the static and dynamic current consumption.

A high static current is usually due to a defective circuit board.

A high dynamic current can be due to restricted movement or a shorted coil.

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Measuring the current consumption of a watch can be difficult and usually involves expensive equipment.

The le arsi tester is an economical way of accomplishing this. It is able to provide a variable power supply and by the sound indicator and LEDs, give an indication of the current consumption.

I was going to buy a le arsi tester but then I discovered that the Bulova Accutron tester that I already owned could do that job too.

Putting an appropriate battery into the battery test clip would also give the correct voltage to power the watch under test. The deflection of the meter will show the current consumption. In this way, the static and dynamic current can be measured.

Accutron testers do come up for sale on ebay occasionally. Sometimes for less than a le arsi tester.

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I've attached a picture of  of the variable power supply that I use of my own design. The meter on top is a Seiko meter of course not made by Seiko and citizen also use the same identical meter. Really nice it has a 12 µA full scale can easily read a quarter of a microamp. There is a minor modification though to get stable readings when looking at current going into quartz watch you need a capacitor so I modified an additive toggle switch on the front of the meter to turn that on and off.

Then I found a couple of other links for you first one is the bowl of a meter and a variable voltage power supply. The second one is Building a Variable Voltage Power Supply - Martin Catt.

http://members.iinet.net.au/~fotoplot/accps.htm

http://www.pocketwatchrepair.com/catt/pwr-supply.php

 

 

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