Note
QST Feb 1972, p. 128.
MT-2000A
QST, Oct 1973, p. 153.
QST, May 1975, p. 164.
QST, Feb 1977, p. 130.
QST, Jan 1980, p. 200.
The Murch UT-2000A is a high-power manual antenna tuner based on a construction project by Lew McCoy appearing in the July 1970 issue of QST, p. 24. It was manufactured by Murch Electronics and is well-regarded in the amateur radio community for its robust construction and ability to match a wide range of impedances.
The difference between the 2000 and the 2000A is that the built-in SWR bridge has been deleted.
Specifications
– Power Handling: Rated for 2,000 Watts PEP (some variations are marketed as 3kW, though 2kW is the conservative standard).
– Frequency Range: Typically covers 1.8 MHz to 30 MHz
Circuit Topology
A modified T-network. It specifically utilizes a ganged split-stator capacitor for the input match, which is a hallmark of the "Ultimate Transmatch" circuit intended to provide a very broad matching range and improved harmonic suppression.
– Inductor: Features a roller inductor for continuous, high-resolution tuning rather than a switched/tapped inductor.
– Input Impedance: 50 Ohms.
– Output Impedance: Capable of matching loads ranging from a few ohms to several thousand ohms.
Features
– The rear panel includes an SO-239 connector for coaxial lines, a ceramic feed-through for a single wire (random wire), and a pair of terminals for balanced lines.
– Internal Balun: Includes a heavy-duty 4:1 voltage balun to handle balanced feeders.
– Mechanical Build: The unit is housed in a large, heavy-gauge metal cabinet. It uses large knobs for the "Transmitter" and "Antenna" matching capacitors and a turns-counter dial for the roller inductor.
– No Internal Meter: Unlike many modern tuners, the standard UT-2000A does not feature a built-in SWR or Power meter. It is designed to be used in conjunction with an external SWR bridge or wattmeter.
References
Technical issues. QST, Jul 1982, p. 39.
