AM Reciever (Reply please! as soon as possible)

[MUNEEB399]

please! see the circuit of AM Receiver in RF circuits in project list and plz tell me that would i use an inductor from market or i have to made it by wounding wire on a ferrite rod and please! tell me that will this inductor act as an antenna?

how to make an antena for AM reciever

 

[audioguru2]

The article says that the author used the ferrite bar antenna coil and tuning capacitor from an old AM radio.

Most AM radios use a ferrite bar with a coil of wire wrapped around it for a tuned antenna.
AM radios about 50 years ago used just a pretty big coil of wire for an antenna.
Crystal radios used a very long wire antenna and an earth ground.

I doubt that you will buy a ferrite bar antenna coil in the market. Instead buy a cheap AM radio and use its ferrite bar antenna coil and tuning capacitor.

The circuit is extremely simple and might pickup a very strong local AM station without an external antenna.
A real radio circuit uses many amplifiers and many tuned circuits for good sensitivity and good selectivity.

 

[audioguru2]

I am sorry to double-post but if you look at the schematic this is not a regenerative circuit. The 120k resistor provides DC negative feedback, not RF positive feedback.

The first two transistors simply amplify the signal from the tuned circuit then one transistor clips the signal which demodulates the AM. It does not have automatic-gain-control like real radios have.

 

[Hero999]

Please don't create duplicate threads and keep questions regarding the same project to one thread.

I've merged the ferrite antenna question with this thread and deleted the duplicates.

Moderator