I recall when 1530 came on the air in early 1970 as WELA (Elizabeth, its city of license), the problem was there was a WERA 1590 in Plainfield, NJ and they did not like the closeness of the 1530 call to theirs.
The owners of 1530 changed the calls to WJDM, the first letters (in their names) of the three owners of the station.
I too recall, in 1970, its (1530) transmitter site being in an empty lot (between buildings) on St. Georges Av., yet after a number of times researching this and with the help of others here on the board all indications were, it was not???
I know on saw it in an empty lot around 1970 between two buildings. on St. Georges Av. ???
Years later the transmitter site, I think moved to Union, NJ.