Mercury Vacuum Rectifiers -- A History

To: "'Tesla List'" <tesla-at-poodle.pupman-dot-com>
Subject: Mercury Vacuum Rectifiers -- A History
From: Tesla List <tesla-at-stic-dot-net>
Date: Sun, 7 Sep 1997 22:58:37 -0500
Approved: tesla-at-stic-dot-net

From: 	Richard Wayne Wall[SMTP:rwall-at-ix-dot-netcom-dot-com]
Sent: 	Sunday, September 07, 1997 5:04 PM
To: 	tesla-at-pupman-dot-com
Subject: 	Mercury Vacuum Rectifiers -- A History

9/7/97

As some Tesla experimenters begin to build DC power supplies, no doubt 
they may consider Hg vacuum rectifiers due to their near 
indestructibility in TC environments and moderately good HV and current 
handling capacities.  I'm currently constructing a DC power supply 
using four 866As and two H&R 5 kV 300 mA transformers in series and an 
LC pi filter.  The 866A will handle 250 mA at ~ 10kV max PIV.  866As 
are also fairly inexpensive ~ $5 new in the box at hamfests.  

Charles Steinmetz while employed by General Electric Corp. around 1910 
experimented with carbon arc lamps for street lighting.  He was 
dissatisfied with carbon arc lamps and being well versed in chemistry, 
invented magnetite (an iron oxide) arc lamps.  The brightness, 
efficency and ruggedness far out shown the carbon variety.  Magnetite 
arc lamps had one draw back though.  They required direct current in an 
America that was well on its way to electrification with alternating 
current.  Steinmetz used brush generators to power his street lamps 
with DC.  Ever the electrical engineer and inventor, Steinmetz next 
invented the mercury vapor lamp which he also powered with DC along 
with his magnetite arc lamps and brush generator.  A very strange thing 
occured.  Steinmetz found that when he used both the magnetite arc 
lamps and mercury vapor lamps in series he could power them with 
alternating current.  Steinmetz had unwittingly invented the first 
mercury vacuum rectifier.

RWW