Note
Radio News, Sep 1956, p. 108.
QST, Dec 1956, p. 195.
Allied Radio catalog 1958 (copyright 1957), p. 229.
Allied Radio catalog 1959 (copyright 1958), p. 265.
Allied Radio catalog 1960 (copyright 1959), p. 267.
Allied Radio catalog 1961 (copyright 1960), p. 283.
Allied Radio catalog 1962 (copyright 1961), p. 412.
The Knight RF Z-Bridge is an inexpensive test instrument manufactured by Allied Radio, designed for measuring antenna impedance and tuning antenna systems.
Frequency Range: Operates from 100 kHz to 144 MHz, covering the 160, 80, 75, 40, 20, 15, 10, 6, and 2-meter amateur bands.
Power Requirements: Requires a low-power RF source at operating frequency (approximately 1 watt or loosely coupled to a transmitter) to avoid damaging the bridge components.
Meter Requirements: Requires an external VOM or VTVM with a 0–2.5 VDC or 0–5 VDC range. If a VOM is used, it must have a sensitivity of at least 5,000 ohms per volt.
Primary Functions: Used to measure antenna impedance, tune antennas to resonance, adjust antenna couplers and matching networks, and determine SWR (standing wave ratio) on both coaxial and parallel transmission lines.
SWR Chart: Includes a durable plastic reference chart relating relative meter deflection (0 to 1.0 relative to full scale) directly to standing-wave ratios from 1:1 up to 100:1.
