Unidentified Sound

[taco6513]

Have been listening to GMRS channels on scan at my base station. I hear my repeater ID with morris  code. I

am hearing something else. I don't think it is an ID. It is to garbled and to fast. 

What does a data transmission sound like? That is what I think it might be.

Thanks

WRCW870

[WRAK968]

try to get a recording of the sound and post it here so we can hear what you are talking about. There are many different types of data bursts and even digital modes and interfering signals that can cause odd sounds. For instance, my dash cam seems to interfere with ch 15 causing static with a "click" sound when its on. This should be fixible by adding a filter but Im too lazy to do it.

[BoxCar]

MotoTRBO is akin to an angry buzzsaw

[berkinet]

Take a look, or listen, at https://goughlui.com/legacy/soundsofhf/index.htm

[ULTRA2]

What frequency is it on and your location when you heard the sound?

[taco6513]

I have recorded and posted this to my YouTube.

 

The link is: https://www.youtube.com/watch?v=st_6NXaJRu8

 

I am hearing this on GMRS Channel 18 on a fairly regular basis. Weatherford OK. 75 miles west Oklahoma City.

 

WRCW870

[JohnE]

sounds like morse to me

[Radioguy7268]

I'd agree - it sounds like morse code at a really fast word per minute rate, and set to a low deviation. If you play around with Audacity, you can probably slow it down & figure out the code.  

 

Are you hearing it at regular intervals?

[berkinet]

It sounds more like RTTY to me.  Did you listen to the sounds on the link I posted earlier?

[taco6513]

I agree it sounds like RTTY. only thing is what you heard is all I get. Can't be much data. I would say Semi regular intervals. What does a GPS data transmission from a garmin rino sound like? That would be short. I tried playing back to my moriss code app. Doesn't get anything.

[WRAF213]

It's really fast (like 50wpm) CW for WQDK421, with carrier at 400 Hz.

[taco6513]

WRAF213, So it is a station ID?

[taco6513]

That call sign comes back to:  INTEGRIS BAPTIST MEDICAL CENTER INC

They are in Oklahoma City and the maximum power of the base station is 67 Watts ERP.

None of the frequency's are close to Channel 18 (462.6250).

That makes no sense?

 

WRCW870

[Jones]

I agree, it is high-speed Morse.  I also copy WQDK421. I'll bet since you are hearing this on a scanner, it is an IF image.  A lot of scanners have an IF frequency between 10.7 and 11.3 MHz, and don't have really great rejection.  A lower image would get you close to 451.400.

 

Also of note: Using the PARIS method of Morse speed calculation, this code is being generated at exactly 60 WPM.

[JohnE]

agreed its a call sign. signal sounds weak at best, as to being an image that's quite possible but I think it sounds like a spur.

I would like to hear that on a receiver w/clean  signal.

to confirm you'll 2 or 3 radios. 2 on their assigned low side freq's and one on the .625 and see if one of them goes out simultaneously. 

[WRAF213]

It's either an IF image (most likely), intermod, or a transmitter spur (highly unlikely). Most FRS radios I'm familiar with have IF frequencies above 20 MHz, but have pathetic frontends that easily unmute to mixed out-of-band signals. Another receiver with a different IF frequency and a stronger frontend, or a properly configured SDR, can determine the nature of the interference.

 

That said, 60WPM is way too fast for legal Part 90 identification; Part 90 requires 20-25 WPM.

[taco6513]

Receiving this on my first generation MXT400 at my base. 40 foot tower and 6db gain mobile antenna with ground plane kit.

This radio has the best reception on any set I have.

Not receiving on a scanner.....

WRCW870

[taco6513]

I contacted the license holder. They weren't to easy to get in touch with. There radio person said they are on digital and have been since 2009. The FCC ID that was listed above they said doesn't ID. There digital systems don't ID either. He said reporting the interference to the FCC would be a waste of time, because the FCC doesn't care about GMRS . It is not bothering me for say. I did go to OKC earlier this week. Have my MXT400 antenna problem fixed. I heard it in OKC on regular 15 minute intervals. The power on the radio's meter was pegged out. Guess nothing else to do but wonder where it is coming from..... WRCW870   

[marcspaz]

Kind of surprising to hear.  I had a harmful interference issue not too long ago.  I went to the owner's and they fixed it in a day.  They had patch on the tower and just fixed it.  I would think people would want to have their gear working correctly and not causing interference.

 

Saying the FCC doesn't care about GMRS is just plain ignorant.  There are groups of volunteers that look for PRS violations and report them to the FCC... and the FCC does take action.

[Jones]

Since the license holder claims they are now digital, you might ask them to whom they sold their old analog system when it was taken out of commission back in '09.  It is possible that it was purchased by an individual, re-programmed to be a GMRS repeater, but the old ID was never re-programmed or taken off.