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So dialing around the ISM band I came across some very wideband beacon-style transmitters. They pulse every second. I recorded them in FM-N, FM-W, AM, AM-W and LSB. Each mode you can hear a little different characteristics. With the attenuator on and in LSB, you can distinctly hear in a three second cycle, data for two pulses then just a carrier, then the whole thing repeats. I have verified that these transmitters are at Mt Scott in SE Portland and Bald Peak in Washington County SW of Hillsboro (two big city/county tower locations).

When parked up at either of these two confirmed sites and the attenuator off I hear four transmitters in the background on LSB, so that makes me think there are two more sites around Portland that I haven't found yet, one possibly somewhere up in Vancouver like Mt. Livingston.

I have asked a friend in Salt Lake if heard there but not.

You can always receive these things around Portland no matter where you are. Tested on the coast this weekend, nothing there.

Also, I recorded this beacon audio with WWV and they match up perfectly for on the second pulses. Is it a localized time standard??

Anyone want to take a stab of other locations of use and purpose?

-K

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Using yesterday's technology...tomorrow!

Just a guess, perhaps polling of water utilities using LoRa
https://www.lora-alliance.org/What-Is-LoRa/Technology

Thanks Rich. I looked into the LoRa system. The 920 and 926 system may be a poling system of some type but not of anything that is high in quantity such as power or water meters.

FWIW, I think I found the power meters for PGE down here in Portland. The numbers don't align with the FCC license for their MS service code, so it could be water meters...I am still checking into it. At home with the 7100 in the garage about 10 feet from the meter I can get it to peg the S meter into the red about once every 5 minutes. The water meter is on the other side of the house.

https://www.youtube.com/watch?v=kiHfFsacC2Y

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Using yesterday's technology...tomorrow!

Some water agencies have their RF monitoring limited to pumps and wells. Keep in mind LoRa is designed for battery power so the polling interval can be very infrequent (weekly/monthly).

You know, I've heard these once before in UHF somewhere...

I'm going to ask around...

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