Hi,

I am thinking out loud about how the semiconductor LED evolved into
the laser diode, by exploiting the synchronized population increase
mechanism to generate monochromatic photon emission. Might it be
possible to scale down this electron mechanism to usable radio
frequencies and end up with a radio transmitting antenna that doesn't
require aerials? Might this device then be termed a radio diode?

A*s*i*m*o*v

.... Anyone not wearing 2,000,000 sunblock is gonna have a REAL_ BAD_ DAY_7

Uh, the wavelenght of light aproaches or is about equiv to the diameter of
an atom... a "Radio Emitting Diode" (RED? as opposed to a LED) would be BIG
to emit frequency on the 160 meter band!

Regards,
John

"Scale up" is probably a more descriptive term than "scale down". Do you
know how big it would have to be?

Roy Lewallen, W7EL

Asimov wrote:
Hi,

I am thinking out loud about how the semiconductor LED evolved into
the laser diode, by exploiting the synchronized population increase
mechanism to generate monochromatic photon emission. Might it be
possible to scale down this electron mechanism to usable radio
frequencies and end up with a radio transmitting antenna that doesn't
require aerials? Might this device then be termed a radio diode?

A*s*i*m*o*v

... Anyone not wearing 2,000,000 sunblock is gonna have a REAL_ BAD_ DAY_7

Asimov wrote:

Hi,

I am thinking out loud about how the semiconductor LED evolved into
the laser diode, by exploiting the synchronized population increase
mechanism to generate monochromatic photon emission. Might it be
possible to scale down this electron mechanism to usable radio
frequencies and end up with a radio transmitting antenna that doesn't
require aerials? Might this device then be termed a radio diode?

LEDs don't emit coherent radiation. All your jumbo "RED" would do would
be to emit wideband noise.

--

Peter

They don't? Then hell--I am throwing this laser led away!!!

John

"Peter Hayes" wrote in message
o.uk...
LEDs don't emit coherent radiation. All your jumbo "RED" would do would
be to emit wideband noise.

It's not THAT wide, is it? Anyone know the Q of an LED? I'd guess it's at
least 10...

I have a high-power LED flashlight, 5 superbright leds in the element... it
is bright, if I bring it near an AM radios I lose all reception... this rfi
is solely the product of the leds, the connecting wires and the
batteries--the flashlight housing is aluminum...
I have never checked just how large a bandwidth the rfi covers...

Regards,
John

Your flashlight likely has a DC-DC converter in it to keep the light
output relatively constant as the battery voltage drops. That would be
the source of the RFI. It's also possible that the LEDs are multiplexed
so that one won't hog all the current as they would if parallel
connected. That also could create considerable RFI. Although the RFI is
radiating from the components you mention, they aren't its source.

Roy Lewallen, W7EL

John Smith wrote:
I have a high-power LED flashlight, 5 superbright leds in the element... it
is bright, if I bring it near an AM radios I lose all reception... this rfi
is solely the product of the leds, the connecting wires and the
batteries--the flashlight housing is aluminum...
I have never checked just how large a bandwidth the rfi covers...

Regards,
John

Well, you might be right at that (and contrary to how you took my posts--I
DO recognize you as an authority which has been around the block many more
times than I), however, I have had that flashlight apart a half-dozen times,
at least, it cannot be found!

But, it is quite possible the current limiter is right on the chip with the
LEDS and potted with it in the LED lenses... all five LEDS run in
parallel....


Warmest regards,
John

John Smith wrote:
"I have a high power LED flashlight. 5 superbright LED`s in the
element...it is bright. If I bring it near an AM radio, I lose all
reception."

I have a Timex Indeglow watch with a fairly dim dial illumination when I
depress the dialstem. It wipes out radio reception too. I suspect that
solidstate diodes are noidy devices. They are efficient though as the
light is not accompanied with much heat. As for diode noise, zeners are
often used as noise generators, are they not?

There are various ways to get an atom`s orbital electrons to move to a
higher energy level. You can throw a stick on a fire or aim an electron
beam on a CRT phospher.. From a laser, we`re looking for coherent
radiation.

Best regards, Richard Harrison, KB5WZI