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Electronics problem, Help required.

I would like to run my new Radio / CD Player from a separate timer partly as bed side alarm and partly as a means to record programs when I'm out.

My multi function timer used to switch my old mains powered radio on by simply switching on the mains supply, but with the new Radio / CD Player the mains power has to be on all the time to maintain the tuning memory etc.

To switch the set on a simple click button is pressed which makes a pair of contacts momentarily, just as a bell push would. to turn the set off the button is pressed once again.

My problem is how to make my timer simulate the pulse action. I have connected a pair wires to the rear of the on/off button and need to be able to connect them briefly to turn the set on or off.

The timer switches mains. There is a ready 12 vdc within the set. I managed to get the required affect by using 3 relays, 2 with 12 vdc coils, 1 with

240v mains coil. But it seemed a rather clumsy way to go about it.

My question is: there another way possible with a switch.trasistor? The two on/off switch contacts need to closed briefly when the mains comes on and again when the mains goes off.

Sorry this explanation is a bit long winded, but to answer it one must understand the question.

Thank you Mike S.

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Reply to
Mike Steward
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I would consider optoisolated switches they are very low cost and simple tio use. You can get them with either SCR , triac, or transistor ouputs. The input is basically an IR LED . You can also get some that are neon driven sop they can run directly off the line ( mains ). I like the lED ones better . To runa LED off the line you can use a capacitor to limit the current ot about 20 mA and diodes to remove the reverse flow. ron

Reply to
ron doctors

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