The stepper presented here makes use
of nine positions of a 12-position
rotary swtch. It is, of course, possible
to add the omitted steps, As usual, the
amplification factors are arrived at by
connecting a number of reststors in
series in the feedback circuit. The resistors
used here are from the E-96 series,
which enable a fairly accurate approximation
of the wanted amplification.
If greater preciston is required, combinations
of two resistors may be used.
This has the drawback, however, that a
make-before-break switch must be used
to prevent the output constantly being
switched to the supply line.