I have had in my possession for quite awhile, a valve characteristic metre and an almost completed copy of the manual. It is by the AVO company, and the model type is: V.C.M. 163. I know that this instrument was used by engineers that designed tube circuits, but does anyone know if they are used today. I had planned to use it for a tube tester, but all I have done is calibrate it for north American line voltage. Any comments?
Thanks in advance.
Bernie.
