inside the case ...

[hueur]

Hello everybody,
I've opened my watch case because the button is too sensitive so I wanted to put some tin foil (as suggested in this forum - it works thanks !). And I saw this strange piece of metal (see photo) !!! what that ? is that an original piece or somethnig put inside by an old owner, an anti-magnetic piece of metal that is not anti anymore ? Is that why my button is so sensitive ? If it is, so how can I remove it to put some brand new anti-magnetic field (sorry I'm not very techie...) ?
Thanks

[bruce wegmann]

That is the button coverplate [these are always made of brass, or some non-magnetic alloy, so as not to interfere with the transmission of the magnetic field between the button magnet and the reed switch]. It is 100% original. BTW, the part Time Computer used to correct an overly-sensitive switch is called a "high-mu shunt". The foil is a magnetically-conductive, high-iron/nickel alloy known as mu-metal [pronounced "mew"].

[hueur]

Thank you Bruce,
Do you think I have to look after mu-metal (there is a shop in Paris) or the alu foil I put inside is still a good choice on the long range ?
In fact the problem was dual :
firstly : when I press shortly the button, just to have hours and minutes, seconds sometimes appear after minutes and hours, and only disappear when I shake my handle (I first thought it was a special feature of the pulsar !!!). This first problem is partly fixed by the alu foil.
secondly : the button is still very sensitive despite the alu foil.

Some people on this great forum talk about electrical tape to cover up the inside button. Wich one is the most efficacious ? Is the mu-metal a definitive solution ?
I am afraid of having to act on the reed-switch in the module (not techie !)
Thank you

[Planet-LED]

I have also had some success with painting the reed switch with automotive touch-up paint. You can apply more than one coat. If you get too much on it, you can easily scrape it off.

[hueur]

Thank you HDLED, this is very interesting. But you mean painting the reed switch (settle on the module) or the metal piece you can see in the above pics ? Can you explain me the exact part to paint ?
Thanks you

[Planet-LED]

Yes, paint the glass reed switch itself that is sitting on the module.