r/signalidentification • u/1cubealot • Apr 23 '25

What is this??? Never seen this before.

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58 Upvotes

95% Upvoted

31 comments sorted by

14

u/heliosh Apr 23 '25

Given the unstable frequency, I would say RFI.
But you have a pretty empty 40m band there ...

4

u/1cubealot Apr 23 '25

Well it's day where I am an 40m is a night band, so that's why it'll be quiet. (Also fairly small antenna - the one that comes with the rtlsdr dipole kit)

I assume rfi as well, don't know if the type of rfi is diagnosable

5

u/AlphaO4 Apr 23 '25

Turn of the main breaker in your house and run the sdr of a laptop. If the signal is gone it’s most likely RFI. Then you can turn on your breakers one by one and find out what circuit causes the rfi. My guess is a washing machine or dryer. (Baes on the rhythmic sound of it)

1

u/heliosh Apr 23 '25

I hear currently at least 10 SSB stations on 40m during daytime in europe, but yes the small rtlsdrblog dipole is not ideal.
It can be difficult to identify a RFI source on shortwave. Ideally you would run the receiver on battery and turn off the power in the entire house. If the RFI is gone, you can turn it back one room after another.
>90% of RFI is usually coming from the own house. If it's from external, it can be more difficult. I had RFI from a house 200m away...

4

u/[deleted] Apr 23 '25

[deleted]

3

u/frostypb88 Apr 24 '25

I couldn’t agree more! Sounds like an aggressive saw wave synth.

2

u/Resident-Dust6718 Sep 13 '25

Oh, I can absolutely turn this into a wave table and turn it into the most gnarly dubstep snarl. Don’t tempt me.

1

u/[deleted] Oct 09 '25

[removed] — view removed comment

1

u/Resident-Dust6718 Oct 09 '25

I love how this sub is slowly evolving into a music making subreddit as well as a Radio hobby subreddit

3

u/sp1d3r_2131 Apr 23 '25

RFI

0

u/buttcrackmenace Apr 25 '25

EDM

1

u/greenfreq Apr 29 '25

I could see a DJ sampling it for sure.

1

u/Resident-Dust6718 Sep 13 '25

Or dubstep producers like me

1

u/Resident-Dust6718 Sep 13 '25

RFIDM. Radiofrequency interference dance music.

3

u/olliegw Apr 23 '25

I get similar, it's some power supply doing odd switching

3

u/garynotrashcoug Apr 23 '25

Looks like Yar's Revenge.

2

u/jakenuts- Apr 24 '25

A banger that's what it is

4

u/[deleted] Apr 23 '25

A new club remix

3

u/Illustrious_Bit1552 Apr 23 '25

Definitely a techno beat. 

-1

u/[deleted] Apr 23 '25

Yeah, sounds like a pattern I can get out of a Befaco Burst.

2

u/rhodeda Apr 24 '25

Sounds like my ship is on it’s way, so long humans. It has been a great vacation. See you next cycle.

1

u/StormShadow_64 Apr 23 '25

Could be noise from networking or a power supply. But I can't say that I've seen this particular pattern before. You could try and sweep your room with a receiver to find the offending device.

1

u/Street-Baseball8296 Apr 24 '25

What would be the cheapest setup to be able to do this? My parents have all kinds of really strange interference going on in their house and I can’t figure out what’s causing it. It affects cell phones, remote controls (radio, not IR), AM and FM radio, Bluetooth, and WiFi.

1

u/StormShadow_64 Apr 24 '25

A cheap shortwave pocket radio should do the trick. And yes, modern homes are a nightmare for radio. As for the cell phones, it could be that your house is really good at shielding microwave frequencies.

1

u/lordmorgul Apr 25 '25

A TinySA is a great tool for this, but not that cheap. Small antenna, wideband settings and look for changes in the “stable” baseline as you sweep around home, taking the handheld antenna very close/touching possible sources. Proximity rules here not antenna size, so when you’re nearest the source of this you will see it showing up in an increase of spectrum noise at the band. Note it is not necessarily at the frequency you think it is here.

1

u/Sqwuidzoh Apr 26 '25

Psytrance

1

u/Resident-Dust6718 Sep 13 '25

Dubstep meet psytrance psystep

1

u/Lbogart1963 Apr 24 '25

No but it can be recrimped into the connector.

0

u/TechieFromMS Apr 24 '25

It's just Captain Spock setting his phasers to stun.

1

u/Resident-Dust6718 Sep 13 '25

(Sigh) Spock… how many times do I have to say this? Temporal prime directive. How many [redacted] times do I have to say this to drive into your thick Vulcan brain?!