HFU HF Underground

General Category => General Radio Discussion => Topic started by: ThElectriCat on September 16, 2018, 1834 UTC

Title: 160-190 Khz licenced users
Post by: ThElectriCat on September 16, 2018, 1834 UTC
I know anyone is allowed to transmit on this band given less than one watt final stage input power (excluding filament) and the antenna is not more than 15 meters in any dimension.
But does anyone even use this band, or are all the signals either unlicensed, or incedental.
I have not hear much on this and, save the odd QRSS carrier, or noise from digital devices, dimmers cars, etc.

Has anyone found out about any other regular users not in the domain of part 15?
Title: Re: 160-190 Khz licenced users
Post by: ChrisSmolinski on September 16, 2018, 1927 UTC
There's a few LOWFERs still on the air, a list is here: http://www.lwca.org/sitepage/part15/lfmain.htm
Title: Re: 160-190 Khz licenced users
Post by: Boriken on September 16, 2018, 2011 UTC
Didn't see any "commercial" licenses listed in the FCC ULS database, wireless.fcc.gov/uls (http://wireless.fcc.gov/uls).

There are a handful of Part 5 experimental licenses, apps.fcc.gov/oetcf/els/reports/GenericSearch.cfm (http://apps.fcc.gov/oetcf/els/reports/GenericSearch.cfm).

The power company has some PLC (power line carrier) systems in use for substation protection.

Guess that just leaves the LW broadcasters.

Scott
Title: Re: 160-190 Khz licenced users
Post by: ThElectriCat on September 16, 2018, 2109 UTC
I was not really looking for lowfers, but more what uses it might have in higher power realms, I know there are no official licensed users, but not every legal user is really listed. lots of military and DOD users are not. I know GWEN used to operate there, but Im curious whether anyone has taken up the slack save for the LOWfers.
Title: Re: 160-190 Khz licenced users
Post by: ThaDood on September 17, 2018, 0453 UTC
Those FM, plug-in, intercoms work there in that band and use the house wiring, i.e. Carrier-Current, at about 10mW RF OUT. Ranges of those outside the intended house vary from being stopped at the very 1st utility transformer, to reaching better than 1/4 mile down the street.
Title: Re: 160-190 Khz licenced users
Post by: ThElectriCat on September 17, 2018, 0720 UTC
Interesting, my LF receiver has FM with a permissible bandwidth up to 16 Khz, I might have to build a carrier current transformer