Mochad X10 Dimmer ... Anyone have one working?

I’ve got an X10 Powerhorn. This is a siren which will sound if you send a sequence of ON->OFF->ON . This device also acts as a chime. The device will chime if you send a sequence of ON->DIM or ON->BRIGHTEN.

I am able to get the siren to sound, but I have had no luck with getting the chime to sound. I’m guessing it’s because I’m not doing something right.

Here’s my item config:

Dimmer Alarm_Living "Living Room Alarm" <alarm> (Living,Alarm,X10Horn,Persist) { mochadx10="b15:rf" }

I’m trying to use a rule with these commands:

	sendCommand(Alarm_Living, ON)
	Thread::sleep(500)
	sendCommand(Alarm_Living, 30)

Can anyone tell me what I’m doing wrong?