The picture shows my part complete valve tester which is closely based on the AVO model 163. The top section is complete and the lower section is awaiting a replacement transformer in order to complete the mechanics and wiring. The two sections will be connected via a multiway flexible cable.

I have added a simple facility to check VR tubes to the original design.

The AVO selector switch could not be procured so I have used separate switches around the outer edge of the upper section.

A 15 way adaptor socket has been provided to connect to an assortment of external sockets or direct on to a valve via flexible cables and crocodile clips.