To open the watch and remove the back of the watch, best use the pocket knife, or similar tool – which the blade is thick and not too sharp.
First you need reverse the watch.
The notch for the blade of pocket knife you will find in the lower right corner of the watch.
* Note … Be careful when opening the watch !
It is best not to open the watch by holding it in your hand only. It’s better to put the watch upside down. Then, at the same time, hold the watch firmly with your left hand and press the watch case against some soft surface. It can be soft wood (as in my case), but the best solution is an ordinary desk and a piece of paper placed on it, or even better, a thin newspaper…
Notch in close-up …
… Then you will have your right hand free. You will be able to operate the knife freely with it, and at the same time, the watch will be firmly supported. A stable and at the same time soft base will also prevent scratching the sapphire glass.
* Additionally, near the place where you open the watch, it wouldn’t hurt to place a piece of cardboard or stick several layers of mounting tape on the watch casing itself. It is very likely that when opening the watch, you will support the knife blade against the watch casing. There is nothing wrong with this; it is often done. However, this poses a risk of scratching or scarring the watch case through the knife blade itself. If you want to avoid this, you can use this method.
I have already opened the watch …
… You also have to be careful not to lose the tiny contact coil spring when replacing the power cell. Losing it will definitely result in the loss of sound in the watch. It’s very easy to lose it. What this spring is and where it is located is described in the post : Citizen No Sound ? No Problem !
What Kind of Power Cell Do I Need ?
The battery you need is classical alkaline battery SR 1120W . I recommend Silver Oxide Battery ( marked as SR1120SW with an additional letter S – silver ) – longer works and does not leak !
Don’t buy the cheapest battery, unknown manufacturers. I recommend RENATA, VARTA, MAXELL, SONY, SEIZAIKEN ( Seiko Instruments ).
Although today batteries supplied by unknown manufacturers may have a capacity of up to 55mAH, i.e. a capacity similar to the capacity of batteries from well-known manufacturers! However, they will almost certainly leak within the next two years, especially at higher temperatures of ~30 °C (~86 *F).
While this is not very dangerous because the watch’s contact plates are gold-plated and the rest are acid-resistant, plastic is also acid-resistant. I know from my own experience that acid does not cause serious damage. After two years of using cheap batteries, all I had to do was wipe off the acid – the battery and the watch still worked !
However, there is a risk associated with condensation of condensed acid inside the closed, hermetic case of the watch – on the inner surface of the sapphire crystal. Of course it can be cleaned, but it may be a bit of a problem for you. It’s better to pay a few pennies and buy a proven battery …
The battery is covered by a small power cell strap – mounted on two small holders .
Removed power cell strap and his holders.
To remove the power cell strap, preferably use a small screwdriver. Just simply slide the metal plate from the holder on the one hand. Now the power cell strip will be removed on its own …
* Note … In newer models of the watch, i.e. from the 1990s and 2000s, the power cell strap may look slightly different - See Here.
The case back ( with visible piezoelectric beeper „piezo buzzer” ) and rubber seal close-up …
„This is a sporting watch witch water – resistance up to 10 atmospheres of pressure „ i.e. 100 m – Citizen’s words .
So, before closing the watch I recommend cleaning the gasket :) .