ser no 370-441
This LOW RESISTANCE test meter by AVO has
two logarithmic scales to 2 ohms and 20 ohms centre scale, it is
measuring fractions of an ohm. There are two insulated screw terminals
on the top. This measures 13cm long (including
terminals) and only 7.5cm wide. The casing is similar in size to the
AVO multminor and includes the later type of meter movement.
low resistance ohmmeter and could not find any reference to this unit
anywhere and send me these pictures. It has a conventional resistance
board with three windings, and a 'high' and 'low' scale. As viewed from
the rear the windings are from L to R- 710ohm 64.3ohm and 2.2ohm
Batteries The meter takes a 1.5V
battery which would
been 'C' size, but can be padded it out to accept a AA battery. Note
when spacing battery compartment with 5p pieces as shown that they are
now steel- old cupronickel ones are preferable.
How old is it? Many AVO meters can be dated from the last 3 or 4 digits of the serial number under the right hand end of the scale. These define the month and year of manufacture. For example this one was made in April 1941.
What is it worth? I think very few of these instruments were ever made so you can expect to pay as much for one of these as a fully functional model 8