Beam Dynamics
Molecular Beam Skimmers





Response Rise time <5 µsec
Useful D.C. Pressure Range 10-8 - 10-2 torr
Sensitivity 1 x 105 Volt torr-1 mA-1
R.M.S. Noise 15 mV, with filament on
D.C. Voltage Out 4 mV - 10 V, over 7 ranges
Oscilloscope Output 0 to 10 V
Emission Current Continuously adjustable, 5 µA - 3mA, over 7 ranges
Filament Current 2 A
Filament Voltage up to 5 V
Filament Potential 2 V
Grid Potential 160 V
Collector Potential 0 V
Power Requirement 40 watts, 115 V/60 Hz or 230 V/50 Hz
Maximum Gauge Head Temperature 70 C

Gauge Head Materials

Tungsten (.005" dia.)
Tungsten (.005" dia.)
Stainless Steel
Gauge Housing:
Gauge Frame:
Stainless Steel
Stainless Steel


Control Unit: 19" (483 mm) wide
  3.5" (89 mm) high
  8" (203mm) deep
Gauge Head: See schematic below

Shipping Weight 12 lb. (5.4 kg)

Guage head dimensions

Mounting Notes:

1. Leave room in mounting plans for the routing of the cable and connector from the bottom of the head unit. Clearance of approximately 1" (2.5) is necessary.

2. The head unit can get hot with the filament on. If a heat sink is required, do not attach it to the op amp, but rather attach the heat sink to the head body or mounting arm. The op amp must float free and not be grounded.

3. The head unit (including the op amp) is grounded internally through the cables to the control unit. The FIG system grounds through the control unit chassis; no other grounding is required.