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Problems with Clap-Activated Relay

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shariqforum

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okay here's this clap-enabled relay circuit i got from some website. but the problem is that its not working!!

the circuit is uploaded for reference at
http://geocities.com/shariqmunir/circuit.gif

the parts list describing the legend is at
http://geocities.com/shariqmunir/parts.txt

the relay schematics at
http://geocities.com/shariqmunir/relay.bmp

i have checked and re-checked all settings. i also have connected a 1k resistor and a diode in parallel with the relay terminals as well.

there was a point in time when the LED was always on and wouldnt switch no matter what- i made fresh connections and now it wont switch on!!

now the Relay is not switching, the diode glows bright red and the battery terminals become really hot and red sparks come out of them!!!

please help me out! what could be the problem?? this is the second relay i have place and still no relief!!
Additional Details

the relay connections were made by a teacher with diode connected in reverse bias at legs 2 and 9 (see schematic).

i am applying 3V batteries to the 5V reed relay

um... unfortunately i havent re-checked the circuit using any test gear after reconnections!!!

oh and yes i'm building it on a protoboard
 

If the batteries are getting hot, then you have a short circuit. Open switch, S1, and check the resistance from across C1. If the resistance is low, start disconnecting parts connected to the positive terminal of C1 until the low resistance is discovered. Most likely parts are Q2, Q3, and IC1.

Since you are using protoboard, also look for stray leads shorting stuff out or wires that are now touching.
 


thanks a lot for your feedback .... i will be looking into the possible problems you mentioned when i get back the circuit from my course coordinator

thanks a lot!
 
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