Russian 6N23P ECC88 6922 Voskhod, grey shield, Kaluga factory marked as PCC88 7DJ8
Now these are a real surprise and demonstrate how the old Soviet Union never wasted anything, I'll bet though that someone who made these error through a vodka fuelled fugue ended up in a padded cell being beaten with rubber truncheons - or worse.
The packaging is Voshkod Kaluga rocket from the late 1960s, early 1970s with the edge of the box labelled 6922 which as we all know is IREC for ECC88. The box ends have 6H14N notation which has been struck through - which is cyrillic for ECC84. Confused, well that is not all for the envelopes are marked PCC88!!!!!!!!
The PCC88 is a 7 volt, 300mA heater version of the E88CC which are absolutely compatible with virtually any product that uses 6922 and 6DJ8. Their sound stage is characterised by smooth highs that maintain extension without being bright whilst showing great detail and texture in the mids.
These 1970s devices have been tested and show full emission and superb matching, will you give these cold war warriors a home in your amp?