Re: WiFi range ...

On 8/3/26 07:22, The Natural Philosopher wrote:
> On 03/08/2026 05:12, c186282 wrote:
>> kind-of EXACT humidity readings are a sort
>>    of black art.
> 
> The presence of a tree exuding transpired water can totally distort a 
> reading
> As cam a crowd of sweaty people

   Immediate environment is indeed a complicating factor !
   Similar issues with getting accurate temperatures. Sun
   hits a dark or concrete patch 50 yards away at a certain
   time of day and it may send a plume of hot air at yer
   device.

   As such, most such measurements are going to just be
   "(maybe) Good Enough".

   There are standards for professional instruments like
   the Weather Service might install at airports and such.
   A certain kind of housing, placement, height and such.
   That doesn't mean the readings are 100% accurate, just
   that they're done in a standard fashion that can more
   or less be compared to similar installations.

   I've used the olde-tyme mechanical drum recorders. It's
   amazing how much "jitter" you could outright SEE on the
   paper. Even opening the instrument box caused the figures
   to jit up or down a little right before your eyes. Means
   "accuracy" here is always a somewhat soft figure.

   Did a one-off climate gadget for a pro greenhouse once.
   They had data saying the crop qual would be best at a
   very specific temperature and humidity. Spent something
   near $400 (mid 80s dollars) on something that'd be
   accurate enough to make them happy. It was a wet/dry
   system (thermocouples I think but can't remember) and had
   a little fan to suck air past the sensors. You had to
   re-fill it with water every so many days. Used an 8051 uC
   for recording AND actuating 'mist' squirters (just a
   solenoid). The clients sold to the 'elite organic vegan'
   crowd and could get top dollar for like mini tomatoes
   and weird salad green shit I'd never eat. Pretty simple
   programming with just a little IQ added to note the
   RATE of humidity change and react accordingly.

   Anyway, a home-grown wet/dry setup is very easy to
   realize using ds18b20s and something even as small
   as a Uno or Pi0. Adafruit(?) does or did sell a
   tiny uC unit (ard compat) with a couple of A/D pins
   and I think I2C and/or 1-wire connections. "Trinket" ?
   Bought one long back but never got around to using it.
   Really small and low power though.