Note
Ham Radio, May 1972, p. 71.
QST, Aug 1972, p. 151.
QST, Nov 1972, p. 162.
QST, Aug 1973, p. 165.
The tuner is designed to operate on all bands 80 through 10 meters, and can handle 1 KW PEP.
For high-impedance feeds the power capability is 350W PEP. The unit works with coaxial and balanced feedlines.
The power dissipation of the air cooled 52 ohm dummy load is a function
of time, and is limited by the maximum allowable skin temperature of the glass tinoxide resistor. A graph of time vs average power is included in the instruction book, and ranges from 15 seconds at 2 KW PEP input to continuous service at 90 watts PEP input.
The wattmeter has two ranges (0-100W and 0-1000W) and measures average power. It is factory calibrated to an accuracy of 5% of full scale. Full scale calibration can usually be achieved with as little as 12 watts on 80 meters. The ceramic switch wafers are operated well within their ratings when the other limitations are observed. The KW107 can be arranged for many switching configurations between a dummy load, two 10, 15 and 20 meter antennas, two 40 and 80 meter antennas, and the built-in antenna tuner.