why use audions in the constant current circuit?

i studied a constant current source circuit showes below,and i don't understand why there are some audions in the circuit, what effect do they take?who can tell me? thanks （/center）

Sorry. "The connection was refused when trying to contact 202.99.23.246"

What's an audion ?

Graham

Change,

The link doesn't work for me, so I can only speculate. If the audions, also known as valves (veddy veddy British) and tubes (crass American) are pentodes, pentodes have a constant current characteristic when the plate voltage is above a certain value. Matter of fact, their characteristics are very similar to FETs, which also exhibit this characteristic, i.e., the current is relatively independent of the Plate-Cathode (Drain-Source) voltage. Regards, Jon

I use these for speaker connections...very effective when used in conjuction with imported galvanized mahogony connectors. When submerged in water they provide a huge damping factor. Regards, Jon

Dr McCoy when they went back in time in star trek

from wikipedia: the name of a wireless signal detector device invented by Lee DeForest in 1906,

martin

"martin griffith" a écrit dans le message de news: snipped-for-privacy@4ax.com...

Well, I first thought these were gold plated, oxygen free phonons.

Hmmmm ... Dr McCoy was played by DeForest Kelley, and the device was invented by Lee DeForest.

Coincidence?

I don't think so.

-a

From memory, it seems to be a term adopted in various theoretical modeling disciplines to describe an overdriven linear circuit that can produce an output still containing intelligible information - a crude demodulator.

Last seem used in article about cmos current conveyors, but I have no electronic article references to offer.

Perhaps the OP could clarify his question using more common terms.

RL

Hello Graham,

This used to be the name for a feedback receiver in some parts of Europe. One where you fiddle with the feedback until you get just the right selectivity. A good design would have a very gentle transition into oscillation, ideally without any hysteresis. That would allow SSB reception.

I built one when I was a kid but it's gone. Wife doesn't like too much of the old stuff hanging around :-(

Regards, Joerg

Definitely not. See my post in the "Beam me up, Scotty" thread.

ISTR in that episode, Bones or someone asked Spock what he was doing (in a room where he has assembled all these 'radio tubes'), and he responded with something like "Making a Tricorder out of bearskins and stone axes." I have little doubt the exact wording is on the Web somewhere.

Also IIRC, having nothing to do with anything but allegedly part of the room-sized vacuum-tube tricorder and in the background of one of the shots, was a Jacob's Ladder.

-----

You mean a *boat anchor* !!

First hit on

Cheers! Rich

But not first hit on a google simply for audion which returned any number of hi-fi links.

Graham