1409-M

The General Radio General Radio 1409-M Standard Capacitor was introduced in Catalog O (1956) and remained available through Catalog U (1970).

The 1409-M is a fixed mica capacitor of very high stability for use as two or three-terminal capacitance standards in the laboratory. The capacitor is installed in an aluminum case along with Silica gel desiccant then sealed with hi-temp potting wax. A well located on the right side of the case for the insertion of a dial-type thermometer. Three jack-top binding posts are provided on the top of the case and removable plugs on the bottom, for convenient parallel connection without error. Each capacitor is supplied with a certificate of calibration giving two and three terminal measured capacitance. The Type 1409-M capacitor is mounted in the small case.

See 1409 to view all the capacitors in the series.

Specifications

• Capacitance: 0.02 μF
• Series Inductance: 0.050 μH
• Adjustment Accuracy: within ±0.05%
• Stability: Capacitance change is less than 0.01% per year
• Temperature Coefficient: capacitance; +35 ± 10 ppm per degree between 10 °C and 70 °C
• Dissipation Factor: Less than 0.0003 at 1 kHz and 23 °C (see curves). Measured dissipation factor at 1 kHz is stated in the certificate to an accuracy of ±0.00005
• Leakage Resistance: 5000 ohm-farads or 100 GΩ, whichever is the lesser
• Maximum Voltage: 500 V peak below 430 kHz

Links

• Experimenter July 1957 describing Type 1409 Series

Photos

• 

  Change in capacitance as a function of frequency for typical Type 1409 capacitors.

• 

  Dissipation factor as a function of frequency.

• 

  Technical Drawing.

• 
• 

  Thermometer Access

• 
• 
• 
•