Other than my service monitor/spectrum analyzer which tunes .450Mhz to
1.0 Ghz FM, (only) I have no way to hear this AM signal. Does anyone
have any ideas? Thanks, Lenny

If you're very near to the transmitting antenna, I'd think that even a
simple un-tuned crystal radio would be sufficient. A length of wire,
a 1N34 diode, maybe a small capacitor, a crystal earphone, and a clip
lead to attach to ground would oughta do it.

If you want to get fancy, add a series-resonant circuit (small air
variable cap and a hand-wound inductor) to tune it to 72 MHz.

A 100 MHz (or faster) oscilloscope with a wire connected to the BNC
jack would probably pick up enough to show you the modulation, if
present.