874-VR
The General Radio 874-VR is a "voltmeter rectifier" with two GR-874 connectors for the signal, and another GR-874 connector for the rectified output. It was introduced in Catalog M (1951) and remained available through Catalog 1973, after which only the 874-VRL version with locking connectors remained in the catalog.
The 874-VR is used in frequency-response measurements with a 1750-A Sweep Drive and 1263-C Amplitude Regulating Power Supply. An 874-VI Voltmeter Indicator can be used for calibrated measurements from 0.1 to 2 V.
It contains a 1N23B diode and a mica capacitor.
The 874-VQ is similar to the 874-VR, but omits the 874-VR's 50 Ω series resistor, and includes matching elements to compensate for the discontinuity caused by the diode capacitance.
Key Specifications
- Frequency range: 15 MHz to 2.5 GHz (correction required above 1 GHz)
- Input: 0.1 V to 2 V
- VSWR: ≤1.1 @ 1 GHz, ≤1.2 @ 2 GHz; rising rapidly above 2.5 GHz
- Resonant frequency: 3.8 GHz
Links
- 874-VRL is the locking version.
- 1N23B Microwave Diode Data