The 1491 Decade Inductor is an assembly of several decade inductor units in a single metal cabinet. The units have no electrical connecton to the panel, but a separate ground terminal is provided, which can be connected to the adjacent low terminal, leading to the smallest decade.
Features:
• Shielded toroidal cores for low mutual inductance and minimal effect from external feld
• Sealed against moisture for long-term stability
• Excellent as a moderately accurate inductance standard
• High Q, 200 and higher
Zero inductance
Approximately 1 µH
Maximum voltage
500 Vrms
1491 switches safely break the circuit at
500 V if turned rapidly, but voltages above
150 V may cause destructive arcing with
the switch between detent positions.
dc Resistance
Approximately 45 Ω per henry
Connection terminals
Two, 5-way, gold-plated, tellurium-copper
binding posts with low thermal emf and low
resistance, plus separate binding post for
ground.
Temperature coeffcient
Approximately -25 ppm/°C between 16° and
32°C.
Mechanical
Dimensions: 43.2 cm W x 22.3 cm W x
16.6 cm D
(17" x 8.75 " x 6.5")
Weight: 10.5 kg (23 lb)