bananasiong said:
the vcc is connected to the +ve terminal of the battery and the ground is connected to the -ve terminal of the battery right? but it doesn't work! i used a cro to measure the output (after the 0.1k resistor), it shows a constant -12v (supply is 12V dc).
the ckt is a normal 55 psc , and it will work .
u have wrongly selected the test point , measure the freq&voltage at the pin3 of 555. the 100R is placed for current limiting at the o/p section of 555.
bananasiong said:
how about the receiving part, the pin 7 of the opamp is connected to nothing?? where is the antenna of the receiver??
thanks for helping me..
the lm393 contains 2 opamps with open collector transistor , we are not using the second half of the ic , and it is left free.
probably u wont require an ant
and it should work in ur case) , the coil will pick the freq. and , if u need connect it to pin 2