Micro Seiki Tonearm MA 505

[vintage1958]

Hi! Does anybody know what mission has the corrugated caster ( diameter apr. 13 mm, location – the long horizontal pin perpendicular to the pipe axle)?
It looks rather incomprehensibly….

[nat]

Are you describing one of the horizontal bars above the actual tonearm? If so, the larger one is used to apply tension to the tracking force wire, and the smaller one is tolocate the pivot point for the wire, and to create antiskating force by displacing this pivot point,

[vintage1958]

Are you describing one of the horizontal bars above the actual tonearm? If so, the larger one is used to apply tension to the tracking force wire, and the smaller one is tolocate the pivot point for the wire, and to create antiskating force by displacing this pivot point,

Thank you, it would be too simple... but MA 505 has one more horizontal bar. It mounted firmly on the arm fork and looks like continuation of the bearing axle. This bar is glossy, you can slide the caster along it.
For example MA 505 III has not this bizarre part at all….

[Yosh]

I have MA-505 first version from 1976:S-shape arm with SME type connection to shell.

The black counter weight is slidable on continuation of the bearing axle bar.
Bizarre at first sight but designed as lateral balance weight
for this S-shape arm. Please look the line from stylus point to arm pivot.
Vertical bearing of this MA-505 is alighed similar to one point bearing arm
- directed toward stylus.
IMO: elbow part (or part of shell) weight of S-shape pipe is to be balanced with this balance weight
though I never acertained the effect actually and put this weight as near as possible to bearing axle.

Regards
Yosh