The QQE03-20 looks to be electrically identical to the QQV03-20. They both have plain glass top and bottom rather than the sintered glass of the QQV03-20A
The heater runs at 6.3 Volts when both halves are in parallel or 12.6 Volts when in series. For 6.3 volts pins 1 & 7 are connected together with pin 5 as the other end. For 12.6 Volt operation the voltage is connected to pins 1 & 7 with pin 5 left unconnected.
In addition to use as transmitter power amplifiers the upper frequency of 600 MHz made them popular for frequency multiplication.
They are rated for audio modulator use but for 21st century audio amplifiers the American pattern 832 gives more pleasing results, not unexpected as the 832 has essentially two small 6V6GT type elements within it.
The two shaped anodes hang from the top of the valve. The common beam place can be seen in the centre.
The top glass has two anode fixings and two supports held within it.
The clear glass base will be hard glass with the tube being of soft glass with a lower melting point.
The wide glass tube envelope is 43 mm in diameter and, excluding the B7A base pins is 67 mm tall.
References: Data-sheet & 1040. Type QQE03-20 was first introduced in 1957. See also1957 adverts.
