GaryP wrote:

...If I set the electronic humidistat to 70%, the unit will run and rather
quickly bring the humidity down as low as 45-55% RH or so, then start cycling
off and on in about two minute intervals (off about two minutes, on about
two minutes). If I set it to 65%, the unit will run for a while to bring
the humidity level a bit lower, then start cycling again. Setting it lower
continues to have the same effect.

Maybe it's working as designed.

...It's just the frequent cycling (literally off and on, off and on, almost
every two minutes) as though it needs to sample the air to determine if it
should continue to run that is annoying and can't be good for the compressor
(both the fan and compressor are cycling).

Can you find the humidity sensor and wrap it in an inch of cotton or
direct the output airstream away from the sensor or move the sensor
assembly to the other side of the room and wire in an extension cord
to power the fan and compressor, under sensor control?

Or set the box to "always on" and power the whole thing with a Herbach
and Rademan (800) 848-8001 http://www.herbach.com $4.95 Navy surplus
humidistat, their item number TM89HVC5203, with a 20-80% range, a 3-6%
differential, and a 7.5A 125V switch that can be wired to open or close
on humidity rise...

Nick