They certainly built these very well indeed in the 70s, and it's still totally original!. Well maybe not the screws on the back! Had to make a special tool to get them out before I could service the thing!
Not a bad component in there except the mish-mash of odd valves. An old Mullard, an ITT, a Seimans and a Teonix. Here's their current draw in mA at 470V:- 32, 24.5, 35.6 rising to 40.2 after a few minutes and 18. On my valve tester, the Mullard tested very strong but is microphonic. Nuff said. A new matched and burned in set ordered. Now to fix the light in the power switch!
Nice trio of long plate ECC83 too!. Not sure of the brand though MValve?