186
8.
ELECTRICITY THROUGH GASES
_
.
The high voltage is supplied by a motor—generator or by a
rectier—lter system capable of delivering 100 milliamperes. It
should be possible to vary the potential from approximately 200
_
to 800 volts.
Fuses (f,f) are provided in both sides of the line and
a protective resistance (R) of, say, 20,000 ohms is included in the
-
anode lead.
The voltmeter
should be of the high resistance
_
type (1000 ohms per volt).
The switch (K) should have a long
insulation handle and be so mounted as to drop open, rather than
closed.
The milliammeter which measures the tube current (it)
should have a range up
to 50 or 100 milliamperes.
The probe voltage (V) is supplied by batteries or a well—ltered
rectier—lter unit capable of supplying 50 milliamperes, and is
varied by means of a slide wire rheostat. The voltmeter (V)
should be of the high—resistance type with ranges from 0 to 15 and
0 to 150 volts.
The milliammeter, which measures the probe eurrent (i) should have ranges from 0 to 1 and 0 to 15 milliamperes.
A fuse (f) and two reversing switches (81) and (82) are included
in the probe circuit.
A complete pumping and pressure measuring system may be ‘
used but it is possible to obtain excellent results with the following .
simple equipment: a mechanical oil pump, an acid bottle With
P205 in the bottom to stabilize the pressure and dry the air, ,and a
Pirani gauge (see section_16—8). All parts are joined with pressure tubing, the pump is kept in operation and the pressure
in the ;
discharge tube is varied by means of a pinch cock on the tubing_
near the pump.
…
_Ï'
Precaùtions.—1. The high potential is exceedingly dangerous,
particularly if the supply is capable of delivering consideràble
‘
power.
2. Watch the probe so that it does not overheat. 3.’ By
'
of a stopcock, connect the pump
to the outside air” before
*
shutting off its motor, particularly at the end of the day, for the
_
'. vacuum can suck the oil ‘out of the pump into the system. ',
_” =
Adjust the
System until the pressure
-
is 0.1—0.2
and remains‘ constant. Stability of both
'
pressure-andLtubeucurrentgis important.
_
the. probe
sOmeWhere
from 7 to
Centimeters from-the anode
and 82 open) turn®n
“
‘
«thÇ.high fV—O1’Càge,Close.Ka'nd;r‘aisè the voltage until the discharge
8.
ELECTRICITY THROUGH GASES
_
.
The high voltage is supplied by a motor—generator or by a
rectier—lter system capable of delivering 100 milliamperes. It
should be possible to vary the potential from approximately 200
_
to 800 volts.
Fuses (f,f) are provided in both sides of the line and
a protective resistance (R) of, say, 20,000 ohms is included in the
-
anode lead.
The voltmeter
should be of the high resistance
_
type (1000 ohms per volt).
The switch (K) should have a long
insulation handle and be so mounted as to drop open, rather than
closed.
The milliammeter which measures the tube current (it)
should have a range up
to 50 or 100 milliamperes.
The probe voltage (V) is supplied by batteries or a well—ltered
rectier—lter unit capable of supplying 50 milliamperes, and is
varied by means of a slide wire rheostat. The voltmeter (V)
should be of the high—resistance type with ranges from 0 to 15 and
0 to 150 volts.
The milliammeter, which measures the probe eurrent (i) should have ranges from 0 to 1 and 0 to 15 milliamperes.
A fuse (f) and two reversing switches (81) and (82) are included
in the probe circuit.
A complete pumping and pressure measuring system may be ‘
used but it is possible to obtain excellent results with the following .
simple equipment: a mechanical oil pump, an acid bottle With
P205 in the bottom to stabilize the pressure and dry the air, ,and a
Pirani gauge (see section_16—8). All parts are joined with pressure tubing, the pump is kept in operation and the pressure
in the ;
discharge tube is varied by means of a pinch cock on the tubing_
near the pump.
…
_Ï'
Precaùtions.—1. The high potential is exceedingly dangerous,
particularly if the supply is capable of delivering consideràble
‘
power.
2. Watch the probe so that it does not overheat. 3.’ By
'
of a stopcock, connect the pump
to the outside air” before
*
shutting off its motor, particularly at the end of the day, for the
_
'. vacuum can suck the oil ‘out of the pump into the system. ',
_” =
Adjust the
System until the pressure
-
is 0.1—0.2
and remains‘ constant. Stability of both
'
pressure-andLtubeucurrentgis important.
_
the. probe
sOmeWhere
from 7 to
Centimeters from-the anode
and 82 open) turn®n
“
‘
«thÇ.high fV—O1’Càge,Close.Ka'nd;r‘aisè the voltage until the discharge