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Crystal Radio only gets a far away station?!

colin55

Well-Known Member
What he is doing is simply putting a diode on an antenna and receiving all the stations at the same time. He is then only detecting the strongest signal.
What he needs is a circuit to provide SELECTIVITY.
This is a tuned circuit consisting of a coil and capacitor. This type of circuit has a magic quality called a "Q factor" and it actually amplifies a particular frequency that is the resonant frequency of the two components.
This is the feature that has been missed by all the previous replies.
 

DerStrom8

Super Moderator
Most Helpful Member
This is the feature that has been missed by all the previous replies.
You're wrong about that. This feature has been discussed in several different posts. It might do you good to re-read the thread.

Regards
 

DerStrom8

Super Moderator
Most Helpful Member
Show me ANYWHERE that the Q-factor of the resonant circuit has been discussed and increases the output of the crystal set.
Oh I thought you were talking about added capacitance :p Hahaha
 

colin55

Well-Known Member
I could see by the replies that no-one really understood the operation of a crystal set. They were all running around in circles about the capacitance and inductance of the antenna.
In fact you just need a water pipe to get a crystal set to work in some areas.
 

cowboybob

Well-Known Member
Most Helpful Member
I guess the point of the OP's question was how to improve his reception beyond the one station he is currently able to pull in.

Perhaps I assumed. incorrectly, that he wanted to do that with his current rig.

Could be wrong about the OP's intentions, (he has yet to respond with a post to this thread).

And who knows? Maybe his tank tap peaks out (not enough turns) at the low end of the broadcast band .

And let's not forget that he's in the hills of West Virginia. No amount of more sophisticated tuning is going to replace the need for a better antenna system, however simple that solution may be.

But as a fan of QRP rigs, it is great fun (and a marvelous learning experience) to see just how little, equipment and sophistication wise, you can get away with and still pick up (and transmit) meaningful AM signals out of the ether.

Judging from his dad's antenna equipment arrays, the OP has an in-house knowledge source. But, not unlike my father, maybe he's being encouraged to figure out his problem on his own. With the gear he has.

Just a thought.
 

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