Sendero,
Interested in what you eventually chose... My mini-clik (similar to above, but non-hunter-branded) is shot and i need to replace. Lowes has the rainbird tray type where two electrodes protrude into the pan, but i have two concerns with that device...
1) the slider for adjusting the amount of rain is way to loose. I don't see how it would ever stay put.
2) if this operates anything like my moisture meter for wood with also as two probes, than it's 24V requirement might indeed means it needs 24V A/C input to function. I would rather just have a manual switch so i can use a standard elk zone...
I just took apart the mini-clik i had, probably pretty old, but i question it's construction a little (the top pin to hold the disks in line was broken and the disks no longer expand a significant amount (i let them soak in the sink, still would not buy me enough expansion to increase to a 1/2 or 3/4 setting)...
-brad