WXPN 88.5 Philadelphia

The "Gross" tower with several FMs on it.

At the very top is 88.5 WXPN (5 bay ERI) and a 2 station main, 1 aux cavity back antenna.

A wider view

The WXPN transmitters, main and aux.

Another view.

The bandpass filter used to keep the other FMs and Channel 6 out of the transmission system and vice versa.