A used Mullard ECC83 long plate valve in excellent working order. It has the very early foil getter and the long 17mm plates.
There is no etched date/factory code on it so I don’t know which factory it was made in, but I assume it was made in one of the Philips factories in The Netherlands. The date is believed to be 1955 because all of the other valves in the record player which it was removed from were dated March 1955. They were from the Phillips Sittard factory in the Netherlands (this doesn’t mean it was made in the same factory, but gives a very strong indication of its age and the company that supplied it to Mullard, who would have re-badged it). The foil getter only appeared on 1955 and some early 1956 ECC83 tubes reinforcing my conclusion about the date (in other words, this design only lasted a year).
The European ECC83 was developed in 1954 making this is one of the earliest European ECC83 tubes ever made.
It has been tested on an Avo Mk3 Valve Tester which can determine both plate current and transconductance, and the readings are excellent (see below).
Actual Readings
Triode 1
ia (mA) - 1.2
GM (mA/V) - 1.9
Triode 2
ia (mA) - 1.2
GM (mA/V) - 1.85
Data Book Specification
ia (mA) - 1.2
GM (mA/V) - 1.6
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