Started 31st January 2019
(Fixing a Model 8 Mark 7 AVO Meter)
This meter was completely non-functioning. Taking it to pieces I found the back contact rotor on one switch was loose. Originally the contact rotor has one plastic spring clip and the shaft below it has another plastic spring clip, together the clips hold the rotor in place and on this meter both clips had broken off (and so are not visible in the photos below).
I drilled a small hole in the shaft to take a tiny self tapping screw, which holds in place a 3D printed "washer" that presses the rotor contact onto the PCB.
- AVO Open SCAD washer - (31st January 2019)
The Model 8 Mark 7 was the last AVO design made, with the final meter leaving the factory in 2008 - see Wikipedia