A new beam tetrode valve likely be of great value to designers of compact audio, video or radio frequency equipment has recently been made available by the Communications and Industrial Valve Department of Mullard Ltd. This is the QV06-20, which has an anode dissipation of 20 Watts. The new valve is intended for operation at full ratings as a power valve at any frequency up to 60 MHz, and at reduced ratings to 175 MHz. It has been designed to meet the requirements of a very wide variety of applications, from servo amplifiers to video modulators, and it will function equally well in radio transmitters as driver, frequency multiplier, power oscillator, or output valve.
A single QV06-20 in Class C will deliver 69 Watts at 60 MHz, while at audio frequencies a pair in push-pull, Class AB1 will provide 120 Watts output. The mutual conductance of 7 mA/V ensures high power sensitivity even at low anode voltages.
As a precaution against internal feedback, the anode is brought out to a top cap and the lower part of the valve is provided with a short metal screen connected to one of the pins. The heater voltage is 6.3 V and the base is International octal. The QV06-20 is a direct replacement for the American 6146.