🚀 go-pugleaf

In article <13404@creare.COM>, kwg@creare.COM (Kent Goeking) writes...

>   I would like to know if there are any materials that demonstrate negative
>   resistance on the macroscopic scale.  I am aware of this behavior in tunnel
>   diodes but I wonder if it might not occur in other structures. 

	Many (most?  All?) plasmas display negative resistance.  Thats what the
	ballast in a fluorescent lamp does, provide a postive
	reactance/impedance to "null" the negative resistance of the arc column.
	(You can use resistor, but its wasteful.)

	With care, one can design an "arc amplifier".  In fact the arc
	transmitters (distinct from spark gap transmitters) of early wireless
	used the arc gain to function as oscillators.

	Roughly speaking, the "hotter" the plasma, the lower the resistance.
	The lower the resistance, the higher the current,
	the higher the current, the hotter the plasma... (repeat until
	fuse blows).  By paralleling the arc with resonant circuit, the current
	change can be coupled to the resonant frequency.
	
thanks
dave pierson			|the facts, as accurately as i can manage,
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