1604-B

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

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

• Experimenter December 1952 describing Type 1604-A
• Experimenter February 1954 describing Type 1604-B
• Predecessor: 1604-A (1952)
• Successor: General Radio 1605-A Impedance Comparator (1956)

Photos

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