A SIMPLE RADIO RECEIVER

[ScienceBorn]

This fascinating project have been concealed in my mind for quite a while, i finally decided to let the cat out of the bag.how to make a SIMPLE RADIO RECEIVER is a project that can be done for fun and it is also mearnt for beginners to have the idea of things in science and also to encourage one to do more research.REQUIREMENT-a variable capacitor, a transistor, a resistor(1ohms), a inductor coil of about 6-7turns, a semi-conductor diode, a ceramic capacitor(102),a headphone/earphone, a antenna(10cm-15cm long), a amplifer(NOTE-a amplifer has eight legs) and a breadbord.the variable capacitor helps to tune the station in other to get the exact station a individual wants,the resistor reduce the flow of current to the device, the inductor coil create a resonator together with the variable capacitor thereby increasing the frequency level of the device, the bread board is a hole-like board were all the connections will be carried out.if you guys are interested on how to go about in the connections email me at [email protected] Have a lovely week guys.

 

[shrtrnd]

Look-up a 'super hetrodyne' radio.
It was our first project in high school electronics class.

 

[ScienceBorn]

What is that all about?

 

[duke37]

We all do this for fun.

I would suggest that you start with a crystal set, using a coil, capacitor, germanium or Schottky diode and a set of high impedance phones. The power comes fron the antenna so needs to be long, say 50m.

Then go to an amplified crystal set using your transistor but a power supply is necessary.
A chip to do this job well was the ZN414 which has now been replaced. Look up the new number.

An amplifier chip may have eight legs or may not.

 

[ScienceBorn]

Where will all the device be connected to? Is it advisable to use a breadboard?.. Will connecting the variable capacitor with the coil wire produce a resonator?

 

[TorontoBob]

We all do this for fun.

I would suggest that you start with a crystal set, using a coil, capacitor, germanium or Schottky diode and a set of high impedance phones. The power comes fron the antenna so needs to be long, say 50m....

I concur with Duke, but remember to have a good ground to the circuit like a waterpipe, and you can usually get away with a shorter antenna.

Also germanium diodes generally are better for this application than silicon schottky diodes, but if you want to go old school, get some galena (a crystaline mineral, of lead sulphide) and use a fine moveable wire (cats whisker) to make one of the connections.

 

[TorontoBob]

A good web site to check out on crystal and simple radio receivers is Crystal Radio Resources http://bellsouthpwp2.net/w/u/wuggy/

 

[duke37]

That looks like a good site, I would go for the MK484 circuit with transistor amp to drive modern headphones.

 

[TorontoBob]

I wish my memory was better or I would have also included this other great resource for very old crystal radio circuits, Crystal Radios & Tube Radios
http://www.crystalradio.net/

It has lots of circuits with information on winding the coils yourself.

Now as an old-timer myself, I remember decades ago when a long passed old-timer showed me how not only did they wind their old coils, but their own variable capacitors, and used galena, natural silicon carbide, and Iron Pyrite (fools gold) as detector diodes.

 

[ScienceBorn]

Really! Thats lovely. You guys shld check out my simple receiver/transistor amplifer which i will paste on this lovely forum soon! It is fun doing this things.