Hi guys,
Im trying to build a simple radio receiver circuit (in a breadboard!) which would light up a small bulb or something.. There are few questions about it which I tried to explain in parts...
Please see my attachmeant below...(I know transistors are not well biased.. but it would work isnt it? the beta value of both of my transistors is between 140-160)
Part 1:
What happened was when i touched the base part of the transistor Q1, the multimeter read about 7.6 volts.. before i touched it, the reading remained at zero volts... I suspected that this happened due to my body itself acting as an antenna and picking up signals from air and this amplified and showed the reading.. plz tell me if my thinking is correct..
Part 2:
Assuming that my part 1 assumption is correct, I would like to know the designing of a filter or something so that only particular frequency passes.. Plz guide me on this too.. See my attachment number 2 which is my idea of the filter (bandpass filter)..
Actually.. I even tried this in my circuit and the problem was the reading in the multimeter was still around 7.6 after some fluctuations.. but it stayed there at 7.6... ... Is my filter working? or is the inductor acting like an antenna or something?
Plz tell me if any info provided by me is inadequate... Thanks in advance...
Im trying to build a simple radio receiver circuit (in a breadboard!) which would light up a small bulb or something.. There are few questions about it which I tried to explain in parts...
Please see my attachmeant below...(I know transistors are not well biased.. but it would work isnt it? the beta value of both of my transistors is between 140-160)
Part 1:
What happened was when i touched the base part of the transistor Q1, the multimeter read about 7.6 volts.. before i touched it, the reading remained at zero volts... I suspected that this happened due to my body itself acting as an antenna and picking up signals from air and this amplified and showed the reading.. plz tell me if my thinking is correct..
Part 2:
Assuming that my part 1 assumption is correct, I would like to know the designing of a filter or something so that only particular frequency passes.. Plz guide me on this too.. See my attachment number 2 which is my idea of the filter (bandpass filter)..
Actually.. I even tried this in my circuit and the problem was the reading in the multimeter was still around 7.6 after some fluctuations.. but it stayed there at 7.6... ... Is my filter working? or is the inductor acting like an antenna or something?
Plz tell me if any info provided by me is inadequate... Thanks in advance...
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