The General Radio 1604-B Comparison Bridge was introduced in Catalog N (1954) and remained available through Catalog O (1956).

General Radio 1604-B
Comparison bridge
General Radio 1604-B Comparison Bridge

Available from 1954 to 1956

Manuals
Catalog History
 Document Year Page
Catalog N 1954 93
Catalog O 1956 31
(All manuals in PDF format unless noted otherwise)

It was designed for sorting, adjusting and comparing two devices at three different frequencies.

Impedance difference can be measured in two ranges, 5% or 20%, selected by a front panel switch, using a built-in generator and detector equipped with a 2AP1 CRT. Balance is achieved when the vertical deflection is at a minimum.

Dissipation factor difference is read directly from the dial in one range. The main change from the 1604-A is the addition of a 400 Hz test frequency.

Specifications

  • Deviation Range: Impedance difference, ±5% and ±20%, switched. Dissipation factor difference, ±0.006 at 400 Hz, ±0.015 at 1 kHz, ±0.075 at 5 kHz
  • Test Frequency: 400 Hz, 1 kHz, or 5 kHz within ±3%
  • Voltage Applied to Unknown: Approximately 1 V for impedances above 500 Ω, decreasing for lower values of impedance

Links

Photos