I picked this one up on Ebay DownUnder and it was in very good condition. It is a 110 Volt AC/DC receiver. It still has the stcker from the folks who sold it new in Minden Ontarion. I had to cheat a little and make a composite photo of this so I could maintain a reasonable resolution image on the web site.
To make this gadget safe I have converted it to 110 Volt operation using the 110 Volt tap on the auto transformer and provided it with a US standard three pin power chord. This means it will be operated from my 110 volt isolation transformer. I will also glue onto the bottom of it a laminated explanation of how it is constructed and how dangerous it would be to operate it without an isolation transformer.
The Tube Tester function is limited to just testing the continuity of the filaments. The common heater pin configurations on a range of sockets are wired in parallel with a neon and two 100K resistors connected to the 110 Volt AC mains. If the neon lights, the heaters are continous. It also has a 12 pin socket on a long lead that I guess was for an early Black and White TV tube. It has four valve sockets and two pin straighteners for seven and nine pin tubes. In addition to the usual Noval 7 and 9 pin sockets it has an Octal and a Loctal socket. Strange for an item from the US to have the Loctal socket.
As the "tube test" function is powered from the 110 Volt AC mains this instrument could be quite dangerous in the wrong hands.
As a Multimeter it does not require the 110 Volt mains connection and the Resistance range is powered from a 7.5 volt dry cell pack. The meter is a crude 1000 Ohms per Volt type which would load down high impedance tube circuits and the readings it provides would be of little use.
It has a two pin appliance socket that I cannot find out why it is there.