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Author Topic: Zinc Negative Resistance Makes 40 Meter CW Transmitter  (Read 3124 times)

Offline ChrisSmolinski

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Zinc Negative Resistance Makes 40 Meter CW Transmitter
« on: June 18, 2019, 1312 UTC »
This project pictured above is like a crystal set in reverse - a 40 meter (7.035 mhz) CW transmitter instead of a receiver.

This 50 microwatt (.00005 watt) transmitter could easily be heard from a distance of 5 miles (straight line GPS distance).

The zinc negative resistance device is easily made by putting a piece of galvanized sheet metal into a propane flame until it gets red hot and flares up with a bright white flame and sparks.

http://sparkbangbuzz.com/zinc-40-meter-xmtr/zinc-40-meter-xmtr.htm
Chris Smolinski
Westminster, MD
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Offline ThaDood

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Re: Zinc Negative Resistance Makes 40 Meter CW Transmitter
« Reply #1 on: June 18, 2019, 1739 UTC »
WHOA!!!! NICE!!!! I see some nice Part #15 applications here. While we're at it, here's the 20M one, along with an 80M link,    http://sparkbangbuzz.com/zinc-20-meter-xmtr/zinc-20-meter-xmtr.htm
I was asked, yet another weird question, of how I would like to be buried, when I finally bite the big one. The answer was actually pretty easy. Face-down, like a certain historical figure in the late 1980's, (I will not mention who, but some of you will get it, and that's enough.) Why??? It would be a burial that will satisfy everyone: (1) My enemies will say that it will show me where to go. (2) On the same point, I can have my enemies kiss my butt. (3) It will temporarily give someone a place to park a bicycle. See??? A WIN / WIN for everyone.

Offline i_hear_you

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Re: Zinc Negative Resistance Makes 40 Meter CW Transmitter
« Reply #2 on: June 19, 2019, 1533 UTC »
That's pretty cool.  All it's missing is some sort of homemade man-powered battery. While it isn't homemade, a thermoelectric generator could probably be used with a campfire or sunlight scheme for grid-down use with this TX.