Surface mount audio transducer on the back of a plate, output through a Shmit Trigger to limit noise, feed to an OP AMP input - have the output stage charging a capacitor with a draining resistor (adjust this to avoid background noise pulses building to a trigger voltage) use a comparator to sense the trigger voltage and use the comparator output to set a latch (as simple as a micro relay with latching feedback) have the latch operate hit light and also a drain switch for the trigger capacitor and put a normally closed MO switch in the latch loop
Regards,
Nick
Registered User
Originally Posted by magicniner
Surface mount audio transducer on the back of a plate, output through a Shmit Trigger to limit noise, feed to an OP AMP input - have the output stage charging a capacitor with a draining resistor (adjust this to avoid background noise pulses building to a trigger voltage) use a comparator to sense the trigger voltage and use the comparator output to set a latch (as simple as a micro relay with latching feedback) have the latch operate hit light and also a drain switch for the trigger capacitor and put a normally closed MO switch in the latch loop
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