They never had a 10 channel system, only 10 sites, and not scrambled in any way. That's a discussion for another thread. I saw that same news article, and best I could tell from the photo which was not good was the tech sitting in front of a what was know at that time as a rat race receiver voter comparator.
In around 1969 they moved from Low Band to a hybrid system of a SP HT200 and Motran mobiles with VHF transmit and UHF receive, and the bases were Motrac 250 watt UHF tube units (monsters that weighed in at around 650 lbs). I actually have one of those units sitting in my shop right now heading to the dump. Along with 3 225 watt Micors heading for the same.
In the late 80's I actually worked on their newer UHF system installed in the early 80's with MT500 portables and Mocom 70 mobiles with Micor 225 watt repeaters located at 3 main 225 watt sites (PS6, North Command,Grassy Sprain), and 2 or 3 additional 110 watt sites which I cannot remember exactly. One was the elementary public school down along the Bronx River Parkway and another was another school East of Central Avenue and Jackson Ave. All the other locations were voting receivers, and believe me they had them hidden in closets and attics of schools all across Yonkers.
I know for sure they were UHF in 1971 as I ran into some buffs at Nathans on Central Ave one summer night and they could only get the mobiles on VHF, because they didn't have a UHF radio. Boy I miss those days.