To some extent I think that even calling it an Alarm logger is misleading and undersells the product. It's a programmable external control module, with four pairs of contacts which will switch up to 1A @ 50v (obviously more with an intermediate relay) and each pair fully programmable to respond to thresholds, high or low, in any of the weather parameters that the weather station can measure (and still function as a standard logger). I can't believe that more users haven't been attracted to use it in all sorts of interesting applications - there are plenty of people that buy the IP logger at the same price as the 6544 Alarm logger, for example. It probably just needs to be marketed better.
Sorry - this has drifted seriously OT.
I think this oversells the product. I've taken a quick look at this and from what I can tell, the console is doing all the heavy lifting in figuring out all the alarms and just clocks the appropriate alarm outputs into the module. It looks like the alarm output module could probably be put together with just a handful of discrete logic chips and some opto-coupled FETs. Take a look at Figure 1 of this app note
. I suspect that some of the unused pins on the expansion interface are what drives this thing.
If anybody has some nice pictures of the circuit board inside an alarm module, please post them in a new thread. Now back to STRMON.
EDIT: Link Fixed. And I'm jealous of those who have already gotten a Raspberry Pi