Study of the Resolution of Monitored Drift-Tube Chambers with Shielded Hedgehog Cards

The analog signals from monitored drift-tube-chambers are lead to the preamplifiers of the on-chamber electronics through so-called hedgehog cards. The performance of the shielded and unshielded versions of these cards regarding the spatial resolution of the drift tubes is compared: the spatial resolution is degraded at most by 8~$\mu$m if shielded instead of unshielded cards are used. Therefore, shielded signal hedgedhog-cards are prefered because of their better protection against pick-up noise.