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circuit that triggers the instant the called party picks


New Member
:roll: pls help me build a ckt.1.) that will count from second to minutes the instant the called party picks up the handset, and simultaneously stop when I put down the handset. 2) a mechanism that accept a set of coins and will switch on the line, ready for dialing. In other words, i want to make a coin phone. I would be grateful if somebody would take a time even just for the first one ( called party "pick up" detection.) thank you.


New Member
If use commersially, I would seriously contact a phone resaler, because building this gadgets may be illegal where you live. Hooking up to the phonelines isn't recommended if you don't know what you're doing. Really.

//Albert "thec" Sandberg


New Member
thanks for the advice

thanks for the advice. Yes, it's for commercial use. my customers has to pay whenever they use my phone and i like it automated. It's hard to find commercially available unit in our place, and its expensive. Anyway thanks a lot.

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