My Sherman 1003 Thunderbolt doing an Alternate Wail signal.

Here's my Sherman 1003 Thunderbolt doing an alternate wail signal or hi-lo wail or whatever you call it. I ran the timer in Attack and switched on the modulator in the RCM 3 manually to do it. I was also running the vacuum blower through it to give it some more kick. There's probably a way to wire it up to do it but I didn't fell like figuring out how to do it. It was hard enough hooking the thing up as it is since I'm stuck using this knee walker.