So I bought two alarms on eBay, both simplex. However, whenever I apply power to them, only the strobe lights flash. The models are simplex 4903-9217 and simplex 4903-9419. The second is a truealert, and I realize its a smart sync model, but what about the 9217? I use 3 9 volt batteries to power them, but only the strobes flash. Please help!!
Did you apply power to the horn? There are terminals for the horn and terminals for the strobe.
Yes to the 9217. But even when I did it just made the strobe flash. The 9419 is a truealert, a non-addressable truealert. And all that one did was flash once…
the truealert is probly smart sync thats why it only flashed once
The Truealert that only flashes once has the older Smartsync protocol. You’d need to pulse the strobe current at 60BPM to get the 60 flashes per minute effect you see on other strobes. I think you can also get a Smartsync module to do this.
The horn wouldn’t sound either…for both of them…I added power to the 9217’s horn connection but still just the strobe flashed…strange…
thats what i said in other wording
And would a 4905-9338 work?
I’m not familiar with the newer addressable Truealerts but I suppose they are two-wire and therefore use Simplex’s newer SmartSync protocol - coded pulses.
Is your Truealert two- or four-wire?
The 9419 is Non-addressable. It’s also part of the 4903 series.
But is it four-wire?
It’s two-wired
Sorry, but I meant to say that it’s the newer SmartSync model. You will need a newer SmartSync module.
that would work but a flasher would also work
I’m looking at smart sync modules. Is the 9983 a good one?
I wouldn’t know. Sorry. 
Well I think the truealert dilemma has been solved, so what about the 9217?
how are you testing the 9217