Billvator
Do you have a print for this job? I have a print from 1958 for 10-21 & 30 UCL controller drawing # C2570152. My prints do not show relays for DHST or XHST. But I have HST.
May I suggest you check the set - reset on the landing coils. Check your floor bars DHS, DCS.
NT I would imagine is your door timing circuit. I would think if it only does it from a down hall call it's in that circuit.
