Credit Card Knife

Economy radar detector

This circuit uses a 1458 dual op-amp to form a radar detector. C1 is the detector of the radar signal. The first op-amp forms a current-to-voltage converter and the second op-amp buffers the output to drive the piezo transducer. R5 sets the switching threshold of the second op-amp; normally it is adjusted so that the circuit barely triggers on background noise, then it's backed off a bit. The response of the circuit may be tuned by adjusting the length of the leads on C1. For typical road-radar systems, the input capacitor's leads should be about 0.5 to 0.6 inches long.



By "Radio-Electronics" Magazine, Jul,86 issue (C) Copyright Gernsba

7 Responses to "Economy radar detector"

  1. has any one try this circuit email me plz mogey336@hotmail.com plz plz :D

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  2. at first glance i think C3 is showing the wrong polarity. The symbol should be reversed I think.

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  3. This circuit uses a 1458 dual op-amp to form a radar detector. C1 is the detector of the radar signal. The first op-amp forms a current-to-voltage converter and the second op-amp buffers the output to drive the piezo transducer. R5 sets the switching threshold of the second op-amp; normally it is adjusted so that the circuit barely triggers on background noise, then it's backed off a bit. The response of the circuit may be tuned by adjusting the length of the leads on C1. For typical road-radar systems, the input capacitor's leads should be about 0.5 to 0.6 inches long.

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  4. WHAT TYPE OF CAP. IS C1 AND C2?

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  5. can I use any other op-amps like LM 324 instead of 1458 ??

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