Table 5.

Voltage-current characteristics for an iron hollow cathode 3,5 mm diam. in helium and argon at various pressures.

Current	Volts
	Helium at			Argon at			Helium-Argon mixture 1:1
A	3 Torr	6 Torr	10 Torr	3 Torr	6 Torr	10 Torr	10 Torr	13 Torr
0.050	230	240	300	240	280	260	220	280
0.10	230	240	300	240	300	300	230	300
0 20	230	240	300	400	310	310	220	315
0.30	260	240	300	480	315	330	200	340
0.40	320	230	300	540	340	3.30	200	.360
0.50	540	230	320	620	340	360	210	370
0.60	580	240	310	700	360	380	220	370
0.70	620	240	300	760	380	380	240–320	380
0.80	640	260	300	820	390	.380	340	380
0.90	680	270	300	870	400	380	360	390
1.00	720	400	300	920	410	380	370	400
1.10
1.20	770	440	310	1000	440	400	400	400
1.30				Arc
1.40	820	460	320		480	420	410	400
1.50
1.60		490	340		510	430	440	400
1.70
1.80		Arc	360		540	440	440	400