The punched-card input for keying the machine is located on the left hand side.

A punched card is placed between the two sets of contacts via a door on the left hand side of the unit.

[5] Other weaknesses of Enigma, such as the regular stepping of the wheels and limited effect of the plugboard were also improved on Fialka.

Design factors in various cryptographic devices can result in the physical leakage of information that may compromise the security of the system to varying degrees.

Fialka draws differing amounts of current depending on which (5-bit) encoded letter is printed or paper punched.

The PSU was designed with a compensating circuit with five artificial load resistors which would be powered depending on the signal from the feedback cable.

[6] In addition to this, the PSU injects a strong noise signal into the power line, to further mask any remaining glitches or transient effects which could compromise the cipher.

The Fialka design is derived from contemporary rotor-based cipher machines, such as Enigma, the Swiss NEMA and the American KL-7.

Fialka is most comparable to the U.S. KL-7 which has eight electrical rotors and also lacks a commutator, but its keyboard permutation switch eliminated the need for a reflector (which had proven to be a weakness in the Enigma system).