The GenRad 1409 Standard Capacitor is series of highly stable, cost-effective capacitance standards. With a low temperature coefficient and low losses, these standard capacitors come in a wide range of capacitance values from 1 nF – 1,000 µF.
From 1 nF to 1 µF, the standard capacitors are constructed with silvered-mica and foil for use as two- or three-terminal lab standard. From 1 µF to 10 µF the units are made of hermetically sealed polystyrene for 10 μF. Above 10 μF the capacitor is hermetically sealed polycarbonate,
Typical capacitors, observed over decades, have shown random fluctuations of less than + 0.01% in measured capacitance with no evidence of systemic drift.
The elements used in 1409 Standard Capacitors are selected for low dissipation factor and are stabilized by heat cycling. They are housed in cast aluminum cases, along with silica gel which provides continuous desiccation. These cases are sealed with high-temperature wax. A well is provided in the wall of the case for insertion of a dial-type thermometer. Three jack-top binding posts are provided on the top of the case, and removable banana plugs on the bottom, for convenient parallel connection without error
For convenient parallel connection without error, three jack-top binding posts are provided on the top case, with removable plugs on the bottom.