Re: Telephone cradle switch(es)
Most '3 wire' telephones -- those with the separate bell shunt wire to pin 3 of the BT socket -- have 2 contacts on the cradle/hook/gravity switch. Both make (close) when the handset is lifted. One connects the telephone to the line, the other connects the bell shunt wire to the 'a' line wire (via a zener network sometimes) to for the anti-tinkle function. In a lot of cases the second contact is designed to make before the first when the hanset is lifted and break after the first when you hang up.
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