When an Avominor needle loses it's red disc.
At certain positions on the scale a Universal Avominor needle is almost invisible once it has thrown it's 'dot'- so it was a case of having a bash at attaching a new dot.
As far as i know the Model 1 pictured (400ohm/volt) always had a dot- but i am not so sure about the Model 2. (4,000ohm/volt)
On assessing the nose/tail balance i noticed the needle was nose-light to the extent that it sat at 4% of FSD (with the scaleplate zero line aligned horizontal.) Conveniently the self-adhesive vinyl black dot plus araldite applied underneath rectified the balance.
The dot is about 1.5mm across! (Trial placing relied on the tackiness of the adhesive backing, then i applied glue.)
The calibration of the magnet needed to be raised slightly- presumably to compensate for the dynamics of the new arrangement.
Dave
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