The ChN-03 cataloged on this blog here is one of the final generation of the famous Electronika digital watches of the old USSR.
For an old-school type watch it is quite advanced.
It has a large display with two full lines of information, various other features, including an automatic timekeeping adjustment, but specifically the ChN-03 version has FIVE daily alarms as I show in the below video which is in Russian but I mainly show the alarm tunes that it can play.
And I also carried out a battery replacement job on it myself.
Just open the back which is easy to do by prying it open gently.
You don't have to unscrew the large plate just remove the little battery compartment thing holding the button in place.
Be careful, it's very jumpy.
New battery installed, it's 392, I think, cover it back which is a pain but can be done ultimately.