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Paul Hovnanian P.E. Paul Hovnanian P.E. is offline
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Default Ambient 7 Day Forecaster

Jeff Liebermann wrote:

On Sat, 25 Jan 2020 17:43:42 -0800, "Paul Hovnanian P.E."
wrote:

No model or FCC ID number anywhere on this thing (it's Chinese).


Lovely. So much for FCC type certification. Probably arrived in the
US by the back door.

Either on
the outside, it the battery compartment or internally.


The label is suppose to be plainly visible on the outside of the unit.

What appears to be
the receiver section has a sticker on it that reads '929.6125'. Taking a
wild gues that this is MHz, that puts it in a pager band.


Yep, that's a pager frequency. Probably USA Mobility running Flex,
not POCSAG:
https://wiki.radioreference.com/index.php/Paging
Are you near one of these cities? If so, I might be able to find the
location of the local paging transmiters using 929.6125 Mhz.


I ran an FCC database search on the 929.0 to 930.0 MHz pager band, centered
on Seattle (close enough to my location to cover reasonable transmitter
sites). No sites are licensed for exactly 929.6125 MHz. But with a wide
bandwidth front end, close enough might work.


I'm wondering about the difference in performance between your friends
unit and yours. My guess(tm) is that there's something wrong with
your receiver section. Open it up and look for a disconnected antenna
connection. If you have a service monitor, try tuning the receiver
for best performance. Maybe replace the antenna with a length of coax
and RF connector so that you can attach an external antenna.


There is no actual wire antenna on/in this thing. Basically just a little
brass bar soldered to the reciever board (a one turn loop). Next time I go
over to visit, I'll bring my unit and see if it loads as fast as theirs.

It is interesting that, when I do get updates, it does a pretty good job,
loading a 7 day forcast for 150 cities in the USA. But then it goes brain
dead and the forcast data ages out. So it does work in fits and starts
(without me having to smack it). When I power it down, the on-screen clock
re-acquires the current time within half an hour. The pager company probably
broadcasts a time signal for all its customers in a somewhat more reliable
manner than the weather data.

On a hopeful note: If the pager company is still maintaining their stuff, I
live about a mile from a major hospital and medical complex. Doctors being a
major customer for paging services, I seriously doubt that a viable paging
company would let their service go to s**t in this area.


I wish I had 900 MHz RF gear to do some testing. Most of my work is down
around 60 Hz.

Thanks for the RTL-SDR and Radio Reference links. I'll do some playing with
those when I get a chance.

--
Paul Hovnanian
------------------------------------------------------------------
Do not interfere in the affairs of dragons,
For you are crunchy and tasty with barbecue sauce.