I'm trying to get C3 to detect RF signals from a mobile phone. Amplify this signal to detect it using an LED. My main issue is simulating the antenna on multisim since multisim doesnt have an antenna!
It apparently does work in real life because of some non-specified behavior, but you can't get anything out of your simulator because it can't simulate the unspecified parts of the opamp.
If you want to test it, you will have to build it for real.
(I can't vouch for it really doing its thing, but the circuit is all over the internet. A lot of people seem to build it and recommend it. None of them says "don't bother 'cause it doesn't work.)
One is based on a diode detector, and the site discusses its performance a little - basically, poor and short range (centimeters.)
It doesn't mention at all how well the CA3130 circuit performs.
The only actual photo on the site appears to be of a third circuit for which no details are given.