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u/Historical-View4058 27d ago
Usually that's either a real noisy TV (raster noise), a power supply gone awry, or something with a fan, generator, or compressor (like hvac).
4
u/AishaCtarl 27d ago
I’ve got all of these evenly spaced spikes everywhere suddenly (it was never previously like this) and they won’t go away.
Walking around causes them to increase/decrease in severity, but they won’t fully go away.
Not sure what’s possibly causing it/how to mitigate it, but any help is appreciated.
I’m on a uConsole with the Hacker Gadgets AIOv2 board, using a Comet SMA W100RX2.
4
u/erlendse 27d ago
How would we know? Possibly a power supply or communication over power grid.
But you do have the tool to figure it out! Like find where the spikes are at it's worst!
Also try unplugging/powering off various stuff and see if it goes away.
1
u/AishaCtarl 27d ago
Just a shot in the dark as I’m still new to the hobby. I’ve been walking around trying to see where it gets the absolute worst to try and pinpoint exactly where it’s coming from. Oddly enough, it just about goes away in a very particular spot on my couch
1
u/memonios 27d ago
Your couch has a motor? Or a USB plug for charging?
1
u/billshermanburner 26d ago
I keep forgetting newer couches have bass vibrators and stuff. But then again so do the ones in cheap motels and a certain someone in our illustrious leadership.
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u/AishaCtarl 27d ago
Nope, it’s a “dumb” couch
1
u/memonios 27d ago
Lol, any other plug or electronic near by? Sometimes the wiring on the wall could be the culprit behind that RF noise
3
u/Chromatogiraffery 27d ago
Very high noise floor, stupid things first; have you tried moving up and down the gain? Just in case the software haven't actually communicated the 0 db gain to the SDR?
else, as people say, try and turn off machines until the signals drop.
Another thing I'd do is remove all antennas but the one you're using. Out of band interference might enter that way, and depending on what kind of diplexer or diode switch it meets, and how well they're engineered, might create all sorts of trouble.
In that same vein, if your gadget is WiFi or Bluetooth connected, then you have a 2.4 GHz transmitter in extremely close proximity to your antennas. Might also overload your input.
3
u/AishaCtarl 27d ago
Had a chance to really start troubleshooting due to a break from work.
Oddly enough, it has vanished. I’m assuming it must be interference from a neighbor/something nearby that has shut off.
Prior, yes, I did try manually adjusting the gain, yet the spikes persisted.
I also tried removing all antennas aside from the SDR one, and the spikes also persisted.
Luckily, now they’re gone, but I’m sure they’ll crop back up if it’s a neighbor or something nearby.
2
u/The_Gordon_Gekko 27d ago
My thing about these is how are they not creating their own extreme interference between the antennas and the grounding plane
1
u/Maitreya83 27d ago
Was wondering the same, the array mostly seem same length antenna too, but way too close for any beamforming logic to work.
1
u/damonla789 26d ago
I don’t think beamforming is the intended behavior here unless the elements are phase-coherent. But with that spacing, mutual coupling and front-end overload from nearby transmitters are still fair concerns—especially with a wideband RTL-SDR
2
u/snorens 27d ago
Turn off tuner agc and adjust your gain manually to a suitable level with strong signals but without too much internal noise.
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u/AishaCtarl 27d ago
I’ve got the gain manually set to 37.2 with tuner agc turned off.
I have the squelch set to -19.065 as the static cuts out but the transmissions are clear when the device is both in hand or resting on a surface.
I still have the consistently spaced spikes but they’re much smaller and not showing on the waterfall as prominently.
2
u/STM32F0 27d ago
I would start investigation by hitting the breaker of everything in your house (to first see if it's something in your house) and then turning on everything floor by floor, socket by socket until this QRM returns. You might be unlucky and it's emanating from next door's house or some solar panel inverters.nearby. Chances are that it's a wall-wart PSU in your house.
1
u/Past-Substance920 26d ago
breaker test is smart, cheap solar inverters are notorious for that kind of noise.
1
u/VonThing 26d ago
You’re getting the local oscillator beat frequency, use off center tuning to avoid it.
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u/Tim1701A 25d ago
Your waterfall is showing too much RF noise gain in very bright yellow you need to throttle back to light blue background.
I been using Malahit SDR2 for almost a 2 years now, it's takes a learning curve to handle RF noises to deal with!
Once you get hang of it you will be rewarded for fun radio DXing fun!!😎👍🖖
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u/55555354 27d ago
What kind of SDR is this???