[Boatanchors] Need Help With Supreme Instr Tube Tester

[Receiver]

I recently received a Supreme Instruments Co Model 503 Tube tester.  Outside 
of cabinet is  good enough that I don't think it will need refinishing. 
Inside it looks quite nice too. The old two wire line cord has been cut off. 
Looked on BAMA and NostalgiaAir and could not find any information.  It has 
a roll chart that's still in good shape, but it looks as if it dates from 
some time before or early in WWII.  It does not have a 9 pin miniature 
socket, but it does have the 7 pin mini socket and most of the early 1X4 or 
5 types are listed.

It has a toggle switch on the panel labeled High and Low.  There are many 
tubes on the roll chart withan * next to them, but unlike the Hickok roll 
charts there are no notes at the beginning or end showing what the symbols 
stand for.

Strange thing though, the rectifier socket has a '01A plugged into it.  This 
might be right, but since the '01A is a lot more rare than the 80 that you 
would expect of that era, I'm questioning it.

I would vey much appreciate any help in obtaining more information on this 
tube tester.

T I A John, W4NET