Gr model 1621 precision capacitance measurement system

Gr model 1621 precision capacitance measurement system

Ultra-Precise Capacitance Intercomparisons
The General Radio 1621 Precision Capacitance Bench Top Measurement System consists of Model 1316 Oscillator, Model 1238 Detector and Model 1616 Capacitance Bridge. All units are mounted in a bench-top rack. The 1616 has the following characteristics.
* 107pF to l0uF 12-digit readout, l0ppm basic accuracy
* 10-10uS to l000uS 5-digit readout, 0.1% basic accuracy
* Three-terminal measurements with 2- or 3-terminal connection
* Simple lever balance with in-line readout
The whole of precision - The 1621 provides ultra-precise laboratory capacitance intercomparisons and dielectric measurements. It is a completely self-contained system capable of capacitance measurements in increments as small as0.1aF (10-7pF) and conductance measurements in increments as small as 100aS(10-10 uS); equivalent to a shunt resistance of 1010M?. Measurements are three terminal, with 2- or 3-terminal connection, and provision is also made for the connection of an external standard for comparison measurements.
Such capability and precision are usually accompanied by restricted frequency and complex operation. The 1621, however, avoids these difficulties. Little degradation of performance occurs from l0Hz to 10kHz and operation to 100kHz is possible. Balances are achieved by in-line readout lever switches - easily adjusted and read correctly. All digits of capacitance and conductance, as well as pertinent multipliers, are also provided by BCD-coded contact closures, available at rear-panel connectors for use by printers or data-processing equipment.
Three integrated units - The 1621 is an assembly of three integrated instruments: A precision ratio-arm bridge, a highly stable oscillator, and an extremely sensitive detector. Most of the bridge's internal standards are enclosed in an insulated housing to reduce the effects of ambient temperature changes; unused standards are disconnected to reduce shunt capacitance at the detector input. The oscillator provides up to 125V or 5A for sufficient signal to be detected even with unbalances as small as one part in 108 of 10pF. The detector contains three meters to help you speed the balance: One displays the magnitude and the other two simultaneously display the in-phase and quadrature components of any unbalance.