CB Radio Talk

For as long as I can remember, from time to time I’ve noticed a certain kind of noise that comes into my receiver in the form of a garbled tone that descends in pitch and fades away much like the keyboard effect that Geddy Lee uses in the beginning of the song Tom Sawyer lol. I also noticed that I could follow the noise by slowly changing channels down until the noise fades away. Now that I use an SDR receiver I can see the signal “walk” across the spectrum display. I never bothered to ask anybody because I thought people would think I’m more than usual crazy lol. This morning I noticed MMM posted a gate showing this so you can see. Does anyone know what causes this or is Geddy Lee playing us all!!!

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Isn't SDR a wonderful thing, I've had the same thing on my waterfall several times and followed it as it went down in frequency, it stopped about 10mhz and turned back up. It sounds like someone with a warble carrier traveling up and down the bands using a VFO. My guess is 3 things, man made,, mother nature,, or those pesky little green guys. Maybe if I see it again I can turn the camera on and get a video to post as well.

3's

Greg

What software are you guys using for SDR?

nosaj

I use SDR Sharp for windows

I need to hook my SDR dongle up again, it's been a while. Do you guys use a USB extension with yours? I bought one to try but never got to it.

I have a SDRPlay RSP1 and I run either HDSDR for SDRPlay or SDRuno (this program is not for a novice). I also have a panadapter on my Icom IC-746 (non pro).

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Greg

Sounds like lightning noise. I got into lightning listening on my short wave receiver long ago.
The sound drifts across the frequencies. Not just crackles and crashes, but moans, whines and whistles too.

MDYoungblood wrote: August 15th, 2019, 6:51 pm I have a SDRPlay RSP1 and I run either HDSDR for SDRPlay or SDRuno (this program is not for a novice). I also have a panadapter on my Icom IC-746 (non pro).

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Greg

Yea I think that's part of the problem trying to learn to use it. I also have a rsp1 and have been trying to use sdruno. What would you recommend for someone just starting that won't frustrate them and leave it behind.

nosaj

The noise could literally be from anything electrical...Stop lights, neon signs, water pumps, bad transformers on telephone poles, even your cell phone charger and plasma TV sets can cause weird noise in your receive....

I have a water treatment plant about 7 or 8 miles from me, that turns something on every now and then and makes a strange noise that I can only hear on channel 23...Got board one day and decided to go on a snipe-hunt and found the noise was coming from the water plant...

Here's what it sounds like:

What do you need for an SDR receiver? Is it expensive or a big chore to set it up?

nosaj wrote: August 15th, 2019, 7:12 pm

MDYoungblood wrote: August 15th, 2019, 6:51 pm I have a SDRPlay RSP1 and I run either HDSDR for SDRPlay or SDRuno (this program is not for a novice). I also have a panadapter on my Icom IC-746 (non pro).

3’s

Greg

Yea I think that's part of the problem trying to learn to use it. I also have a rsp1 and have been trying to use sdruno. What would you recommend for someone just starting that won't frustrate them and leave it behind.

nosaj

Go to the SDRPlay website, click the “Start Here”, re-register and download the HDSDR program. I use it when I just want to scan through the band to see who’s on.

3’s

Greg

Bluerunner wrote: August 15th, 2019, 7:39 pm What do you need for an SDR receiver? Is it expensive or a big chore to set it up?

For me it’s just another toy to play with. Best way to find out the cost is to search the web for “SDR dongle”, there are cheap ones that will get you started to expensive ones that have quite a bit of bandwidth. All it takes is a pc or laptop, plug it in to the USB port, download a program like HDSDR, dial in the frequency and click on the spikes in the waterfall.

3’s

Greg

I have SDR Play RSP2 box and use the SDR-console-Version 3 software that I downloaded from their web site. They have a YouTube channel with a video that walks you through the download process. Here is a video I did of me babbling and fooling around with mine right after I got it all up and running. Basically making a jerk out of myself as usual so be ware! lol. I have another video of how I use the MFJ-1708 to switch between the SDR to receive and transmit on my base station. But for now, one moronic video at a time lol.
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I've read some of these noises are some sort of frequency scanning over the horizon radar used by the Russians. Similar to the Russian Woodpecker we'd hear in the 70-80's but a different system.

It might be someone close sweeping the spectrum with a ant analyzer or grid dip meter. Not that I would ever think up such a thing. HHHHMMMMMM wonder if I can drive a one pill with a mfj259?

nk14zp wrote: December 8th, 2019, 3:49 pm It might be someone close sweeping the spectrum with a ant analyzer or grid dip meter. Not that I would ever think up such a thing. HHHHMMMMMM wonder if I can drive a one pill with a mfj259?

No, I've chased one with my SDR, I heard it on 27.385LSB and followed it to below 10mhz and saw more about 5mhz apart, some stronger but mostly weaker in signal. I do remember the Russian "Woodpecker". I'm still betting on it being "little green men"

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Greg

You can bet your bottom dollar the sweeping carrier up and down interference is caused by a close proximity switching power supply.
We switched to a linear power supply Astron VS70 and the sweeping carrier disappeared.

Island_0860 wrote: July 7th, 2020, 10:39 am You can bet your bottom dollar the sweeping carrier up and down interference is caused by a close proximity switching power supply.
We switched to a linear power supply Astron VS70 and the sweeping carrier disappeared.

Hey, been that route. This signal wonders up/down the band and I'm not the only on the has it at the same time. A couple hammie locals text me when they see it and we all follow the signal.

3's

Greg

Maybe it will shed more light on the little bugger when you actually see it on an SDR. Hard to explain what it looks like. Kind of looks like a little amorphous blob that rolls across the spectral display lol. He's kind of shy and doesn't show up too often but if he does, I'll try to catch him on a videogate and post it up!

Very likely caused by induction heaters in factories or possibly even diathermy. These devices use the ISM band that happens to fall within the 27MHz CB band and has to share some of the band. Often when these large devices power up their oscillator coil will produce a lot of heat quickly which lowers oscillation rapidly causing that swooshing downward effect when mixing with CB radio carriers. The devices aren't suppose to release RF very far away but when skip comes in the inevitable happens. For more info look at..
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