The Gold of the Fool and the Whiskers of the Cat

RE: The Gold of the Fool and the Whiskers of the Cat

e14phil — Wed, 14 Jun 2017 11:27:10 GMT

[mention:4f57fc9d538949ad9eb336ddb9469bb8:e9ed411860ed4f2ba0265705b8793d05] This is one of the best piece of practical experimentation I have seen in ages! What great work :-)

RE: The Gold of the Fool and the Whiskers of the Cat

jw0752 — Wed, 14 Jun 2017 04:26:29 GMT

I love this kind of off the cuff experimentation. Pretty cool. One of my scout manuals had instructions for making a crystal set ( back in the 1950s). The crystal was perhaps a piece of pyrite I am not sure. I made the cat's whisker out of a bent safety pin. The capacitor was tin foil and wax paper and the coil was enameled wire wound on a paper tube. After I wound the coil I used sandpaper to sand off an area of enamel and built a wiper to slide over the bare wire to produce a variable inductor. Thankfully there was a fairly powerful AM station in the area and the thing worked. I am not sure that it worked because it was functional or just because there was enough field density in my area to pickup that station on ones tooth fillings.

John

RE: The Gold of the Fool and the Whiskers of the Cat

dougw — Wed, 14 Jun 2017 03:48:18 GMT

This whole topic is quite intriguing.

Now you got us thinking ..... what is the breakdown voltage? If you crank up the voltage, does it hang in there?

Not to put you to any trouble or anything, but you might be onto something that could have real applications....[View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-6586563a-bb79-4a76-8dda-161ac60e9161/contentimage_5F00_930.png:16:16]

That smooth transition to cut-off reminds me of some holy grail audio characteristics.

RE: The Gold of the Fool and the Whiskers of the Cat

DAB — Tue, 13 Jun 2017 18:59:36 GMT

Excellent job.

Now if you want to know something really cool, I can show you why permanent magnets work.

DAB

RE: The Gold of the Fool and the Whiskers of the Cat

shabaz — Tue, 13 Jun 2017 18:18:47 GMT

This is great to see! It's one thing to read about such things being possible (I remember reading a rusty razor blade can also create a similar effect) but it's a very different thing seeing it for real on a 'scope.

RE: The Gold of the Fool and the Whiskers of the Cat

balearicdynamics — Tue, 13 Jun 2017 17:01:28 GMT

The "radio" based on the crystal was the absolutely first stuff I have done when I was about 10 y.o. Synth was based on the semiconductor crystal (it was the early '70 so these stuff was not difficult to find. By one side the crystal was pinched in a alligator and by the other side it was possible to "synthonize" the radio station with a pin touching different points of the crystal. The "amplifier" was just a aris insulated variable capacitor and a couple of earphones. The antenna was something like 100 meters of insulated copper in spiral (5 meters spiral). Then no power was needed, and the audio was fantastic.

As I find it I have again the model and I will make some photo.

Enrico

RE: The Gold of the Fool and the Whiskers of the Cat

dougw — Tue, 13 Jun 2017 16:56:18 GMT

Awesome. I had no clue this was possible.

Of course you know we are going to be asking if a transistor is possible....

RE: The Gold of the Fool and the Whiskers of the Cat

rachaelp — Tue, 13 Jun 2017 15:49:46 GMT

Very impressive. Whatever made you think of doing this?

I don't have a badge, but you can be awarded Top Cat of the day if you like?