KT66 Marconi oversize glass black plate smoked glass red label holy grail EL37 CV1075 6L6G quartet

Description

The Marconi KT66 is a tetrode having an anode dissipation of 25 W.

It may be used as an audio amplifiers or an oscillator and radio frequency amplifier

As an audio amplifier up to 50W may be obtained from two valves, tetrode connected. As a push-pull triode it has no equal for use in high quality equipment when an output of 14/15 watts is required.

The KT66 is very robust, both electrically and mechanically, once it is suitable for many industrial applications.

This section attempts to cover all KT66 made from the post WWII till the 1960s

Matched quartet KT66 Marconi red and green logo black base, smoked glass with full cup getter! Round KT66 decal, must be rare in such a superb condition.

The quartet KT66 Marconi logo, you see here are oversize glass that means they are about 6-8 mm taller than a standard KT66 can be.

Late 1940s valves with stunning sound like all KT66s.

When the KT66 was launched it was named the Finest Audio Tube ever made!

KT66 Osram smoked glass tested at 6.3 Volts filament

Anode and Screen 250 Volts

Negative grid – 15

Current 65mA

mA/V 6.3

Tested with AVO VCM 163 at: 81mA, 81mA, 80mA, 80mA 100% emission and working order