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Author Topic: Simple Fox Hole Crystal Radio  (Read 4706 times)
Group: Guest
Hi All,

Working on a Tesla free energy experiment, I has so much of a hard time get this radio to work. It ended up of being weak signals due to the big hills in N Pa.

I'm in Allegany State Park, lots of tree that is blocking most signals.

This is my crystal radio late at night, due to weak signals.

https://www.youtube.com/watch?v=sr6rxKBYAhQ

Tom

   
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You don't show us your aerial. crystal sets need a huge aerial.
   
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Hi Paul,

Yes I did, it's on this youtube video. Its about 300ft long and 40ft-50ft in height.

https://www.youtube.com/watch?v=oiniJtLwhvs

Tom
   
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Hi Paul,

Yes I did, it's on this youtube video. Its about 300ft long and 40ft-50ft in height.

Good, and it is thoroughly insulated at the tree end, isn't it? Also, do you have a very good earth connection, maybe copper tubing hammered three foot into the ground? don't forget that water pies are sometimes no good because plumbers use plastic tubing.
   
Group: Guest
Hi Paul,

Yes insulation is well done, I even put a brass rod 3ft in the ground.

I believe this winter is where the power starts to flow from the static charge in the air is alot when temperature reach below 32deg.

It's green and lots of trees, so I think water in the air has a lot to do with it.

Tom
   
Group: Guest
Tommy,


While the grounding and antenna are incredibly important the detector can be the biggest loss of performance.

The problem is the forward voltage of the diode. The higher the forward voltage the stronger the signal must be before the diode will pass the signal.

This is why the venerable 1N34A was used for this purpose. It was of the germanium type with the low forward voltage of 0.3V.

Even when I used a regular old cat's whisker setup most of your time was spent locating the best point for connection having the lowest forward voltage.

My guess is that you could drop in a small signal diode and hear many more signals.
   

Group: Tinkerer
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Posts: 3055
Speaking of Diode Losses;

Attached is one solution.

Quote from: WaveWatcher
Even when I used a regular old cat's whisker setup most of your time was spent locating the best point for connection having the lowest forward voltage.

Aye, those were indeed the days!  I used to order Galena or
Pyrites crystals, mounted in lead, from Allied Radio in Chicago
for 5 cents each.  Searching the crystal surface for sensitive
spots was almost magical.

We experimented with other materials too.  A favorite for
"emergency" radios was a piece of pencil lead and a Gillette Blue
Blade.  The blade worked with other "cat's whiskers" too like the
pointy end of a safety pin or even a small copper wire.
« Last Edit: 2014-08-21, 01:15:16 by muDped »


---------------------------
For there is nothing hidden that will not be disclosed, and nothing concealed that will not be known or brought out into the open.
   
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Posts: 1579

While the grounding and antenna are incredibly important
If, at this time of year, the ground is dry, it might pay to remove the grounding  rod, pour water into the hole, and then hammer the rod back in again.

You might bear in mind Tesla's 685957 (Patrick's chapter 7):

http://pat2pdf.org/patents/pat685957.pdf

and his capacitor methods at 577671 since the capacitor may be more critical than we imagine.
   
Group: Guest
Hi Paul,

Yes I agree, the diode does effect the strength of the signal.

I'm just being cheap, and wanted to do it in a cost effective way.

Tom O0
   
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Posts: 1579
Hi Paul,

Yes I agree, the diode does effect the strength of the signal.

I'm sure diodes are important but the second Tesla patent, 577671, discloses an elaborate way of making improved capacitors. He must have reckoned that they were crucial too.

My question is: Are modern caps good enough not to need to bother with Tesla's rigmarole which was described in order to improve on the poor quality then available??
   
Group: Guest
My question is: Are modern caps good enough not to need to bother with Tesla's rigmarole which was described in order to improve on the poor quality then available??

It is clear that Tesla new his caps but the technology had already been pretty well developed before him, for his time.

Reading the patent, He covers most of the bases for good cap design. Modern cap design makes use of his 'rigmarole'. However, I have no doubt today's cap designs far exceed the earlier designs by a long shot for any application.
   
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