The other peculiarity one should be aware off are the
very strong magnets. The so called 'iron core' does not
allow strong magnets. That is why Lukatschek uses ruby
plates for the coils. One should be very careful with
(fastening) screws as well the nearness of other carts.
Because of the open bottom a screw can get 'fastened' to
the coils instead to the threads . My comrade Don broke
the coils of his ,uh, Ruby 3 by traing to get his screw
back while my (small) Hiyphonic MC-A3 was nearly killed
by 'embrace' of the 'big' LP S.