Learned a lot from you today thank you!

I have a tube tester from 1930 and one from 1958 and they still work.

Super helpful my friend. Thanks

The Sencore label is supposed to go on top of the  meter.

The Jackson looks a very nice tube tester. The US seems to be blessed with a lot of different testers. Many years ago I threw away a Hickok (or the US military version) but back then I had zero interest in electronics. No idea what it was doing in the UK (it was 110V) but I guess it came over with the military.

Interesting on the Sencore it's called a "checker" on the cover but "tester" on the unit itself.

If someone etched the numbers in panel try using a marker over the area then rub off excess so its just showing numbers in black

Maybe someone should build an electronic tube tester - Just plug in the tube to the socket, enter the model number in your PC and let the logic gates and MOSFETs do the magic... It could even do the shorts test automatically, select filament and plate voltages and read all the parameters you'd like, just with a click of a mouse...