Jump to content

Recommended Posts

Posted

I have been monitoring all the channels and a few high power inherent channels.

I am getting a transmission that sounds like a string of DTMF tones.

Any ideas what that is?

Thanks

WRCW870

KI5GXD 

Posted

I hear DTMF tones all over Nebraska on MURS.  I looked into it a year ago, and found out that several farms in the area use MURS for a remote monitoring and telemetry system for their crop irrigation systems and water wells.  There is also at least one company making MURS remote alarm systems for farm buildings and gates.

 

MURS is legal for all of those kinds of things, so that's likely what you're hearing.

 

Most people using MURS for these types of operations do not even know what frequency or band they are using.  All they know is that they purchased this wireless thing that lets them know back home when someone opens the pasture gate, and they have another wireless thing that tells them how many gallons per minute the pump is flowing.

Posted

Yeah, I've heard them too, but in the past, nowadays MURS is pretty dead around where I live. I've done some data telemetry with packet radio, fun stuff... 2W with a good antenna will reach ridiculously far if placed at the right location... my record was 30 miles, but one of the radios was strapped to a drone... so I guess that doesn't count... :D

 

G.

  • 2 weeks later...
Posted

I hear DTMF tones all over Nebraska on MURS.  I looked into it a year ago, and found out that several farms in the area use MURS for a remote monitoring and telemetry system for their crop irrigation systems and water wells.  There is also at least one company making MURS remote alarm systems for farm buildings and gates.

 

MURS is legal for all of those kinds of things, so that's likely what you're hearing.

 

Most people using MURS for these types of operations do not even know what frequency or band they are using.  All they know is that they purchased this wireless thing that lets them know back home when someone opens the pasture gate, and they have another wireless thing that tells them how many gallons per minute the pump is flowing.

Are you thinking of the Dakota Alert gear? I’ve got four of the handies, three bases, and two antennas for them, and I can’t say anything unkind about them other than there should be screwhead-mounting-keyholes on the base for wall mount, and the handies don’t feel super sturdy. They take AA batteries, rechargeable, and are clearly designed for low lifetime cost of operation (you can use Eneloops, and only replace the one bad cell at a time). Proprietary antennas, sadly, but they’re replaceable. No scan function. No big deal. They’re serviceable workaday radios that don’t break the bank designed for rural living, not industrial abuse. I’m tempted to buy a few of their sensors, and build a perimeter around my house, but I know that’s silly and excessive, and it’s an expensive project that’s just for fun. :D It’ll wait until I have more hobby budget, though.

 

On that topic, I’m pretty sure my mystery MURS message (there’s a Morse ID somewhere in those recordings...) is farm telemetry. Smack in the middle of Wedgefield Florida, with three big radio towers in view, is some kind of automated telemetry. Either a farmer’s, related to that tower, or maybe beamed down the high-voltage powerlines I’m about to drive under, it really seems like some kind of low-bandwidth M2M machine-to-machine telemetry.

  • 5 months later...
Posted

When I travel to Asheville, NC, I pick up a very strong signal on MURS 5 and it is a series of tones.   I first hear it as I get into Old Fort, NC and it fades as I get towards Asheville.  I like to scan as I drive a long and this signal interrupts my scanning and is quite irritating to hear so I just blocked that channel from scanning.

Posted

Unfortunately data transmissions are allowed on any MURS channel. While the FCC requires monitoring for activity before transmitting I seriously doubt for automaticity operating stations they employ “busy channel lock out” and just key up regardless.

 

Even with a max power output of 2 watts and a simple antenna a data transmitting station can ruin a given channel for a 1 to 2 mile radius with frequent use. With only 5 channels it doesn’t take many stations keying up automatically to ruin things for MURS in an area.

 

I remember driving through a particular area near me frequently and could always count on picking up a data burst every few minutes on one of the channels. That went on for months. Eventually I locked it out of the scan list in my mobile Ham rig. Like you I found it very annoying. Lately about the only thing I do hear is the local Walmarts, Sams Clubs etc. and seldom at that.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and Guidelines.