Using a PC sound card to receive VLF radio signals

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Just connect an antenna to your computer's microphone input, and you can receive VLF (Very Low Frequency) radio signals! A sound card (or built-in sound chip) with a recording sampling rate of at least 96 kHz is recommended.
Example of using this method to receive VLF signals from Russia and Europe:
• Excellent VLF receivin...
SDR Sharp software (for Windows) to receive and record VLF (and many other) radio signals:
sdrsharp.com/#download
Similar SDR (Software Defined Radio) applications are available for Linux and Mac OS.
Lists of VLF stations:
sidstation.loudet.org/stations...
www.smeter.net/stations/vlf-st...
Common sources of radio interference and recommended solutions:
www.ccrane.com/!wcjHVrOwu6BDBD...
About the accidental recording of VLF station GBR (16 kHz) contained on Mike Oldfield's "Tubular Bells" album:
alancordwell.co.uk/personal/in...
gkircher.stormloader.com/vlfcd/
en.wikipedia.org/wiki/Rugby_Ra...

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7 мар 2015

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Комментарии : 340

@VectrexRoli 9 лет назад

This was the most interesting video I have seen on RU-vid for a long time.

@VectrexRoli 9 лет назад

***** I really have no clue what you want to say with that. ;-)

@feketetv 9 лет назад

VectrexRoli MAGYAROK MINDENÜTT!!!!!!!!!!!! :D

@TheBanMan 5 лет назад

Nice to see a video on low frequency radio that isn't conspiracy theory BS. Good upload!

@daveb5041 6 лет назад

The easiest way to make a really good ground is to take just a four foot long copper pipe from the hardware store and hammer, don't bury it, in to the ground with 4" sticking out. The ideal length is 8 feet as any longer adds no benefit but pounding 8 feet without hitting rocks isn't possible in some soils especially the east coast above Maryland. Take steel wool and get the end of the pipe shiny, then take a piece of stripped copper wire and wrap it around the top of the pipe 10 times and solder it to the pipe if you can use a soldering gun DO NOT use flame it won't conduct. Wrap this in electrical tape to stop oxidation. Then lay that wire above the ground directly to the back of your receiver or antenna balun Makes a night and day difference clears up most noise and reveals stations that you couldn't hear.

@mannys9130 4 года назад

If the dirt is too hard to pound a 4 foot copper pipe like here in the Arizona desert, you can dig a trench that's a foot or 2 deep and 6-8 feet long, line it with a bit of salt, and lay the pipe in and bury it. If it's summer and the ground is dry, keep that area of dirt wet when you want to use the ground. You can definitely use a flame to solder the pipe; it makes sbdolutely no difference how you melt the solder. Use flux for a very good solder joint and clean the copper with Emery paper before soldering. Those without the ability to do this can use their water pipe that comes in from the water meter underground.

@guillermoraigorosky6918 Год назад

Incredible! I just to discover this in an article of the magazine of Argentine Radio Club! I'm ham radio operator for more than 40 years and sound engineer and Mike Olfield's fan, this drives me crazy!! Thanks for sharing!!

@JanusCycle 4 года назад

Thank you, I really enjoy seeing technology used in unintended ways. The Mike Oldfield connection was fascinating.

@DanielBerzinskas Месяц назад

Why has nobody liked this comment?

@TerryMcKean 3 года назад

Thanks again for creating this video, VWestlife. :-) I first saw it when it first came out 5 years ago, and have been having a blast experimenting with SDR-Sharp and similar programs ever since. :-)

@TerryMcKean 9 лет назад

Thank you for sharing this experience...I d/l'ed SDR # and it works very nicely with my Dell D630 laptop and about 100 feet of wire laid right on the ground and link-coupled to a coil wire wrapped around a 5 gallon bucket, coupled to the mic input jack through a couple of transformers audio transformers....works beautifully. Minimal AC hum, and I see the sub broadcast signals at 21.4 and 19.8 and 23.2 and 24.0...21.4 is the strongest here in the central coast of California ...I've had this system going now for almost 1 week and am having a blast exploring the VLF world :)

@lmull3 9 лет назад

That is beyond awesome. I need to try this sometime.

@nt654321 9 лет назад

Just looked through some other 70s albums to see if they should have something similar to the signal on "Tubular Bells", and I found out that Pink Floyd's "Atom Heart Mother" has the GBR signal as well! It's not as strong as on "Tubular Bells", but it is there about 2 minutes in on the track "Atom Heart Mother Suite".

@fungo6631 2 года назад

I am pretty sure most of these were intentional, and were added as an easter egg.

@sonus289 2 года назад

Cool ill check that one out !!

@SteveWrightNZ 9 лет назад

Thanks for the heads-up on the Tubular Bells album, thats pretty cool!

@MichiganPeatMoss 7 лет назад

Very well organized - nice video, description, and helpful links.

@danielpiccoli6833 9 лет назад

Nice work and interesting fact about the already quirky Tubular Bells classic.

@frg9600 Год назад

Very interesting video, thanks for sharing! I have a Yaesu FRG-100 that tunes down to 50 kHz, so about all I've heard on the LF band is WWVB on 60 kHz, and LORAN on 100 kHz when it was still in use.

@TravisTev Год назад

Funny… This channel had me reading online about radio technology out of curiosity, and when I read about VLF I casually started wondering if you could stick a free wire or antenna of some sort into a sound card's input and pick signals up. Then I came across this video. :)

@punishedexistence 9 лет назад

This was the coolest thing I have seen in many a day. Thanks for doing this! I loved it.

@robinwells8879 4 года назад

Very enjoyable demonstration. Thanks.

@TheShaunksread 6 лет назад

That's great, I have a HF communications receiver that tunes from basically 1khz to 30mhz (AOR 7030) and with a metre diameter magnetic loop I can pick up 60khz and 77.5khz time stations and can sometimes hear the alpha signals but it's nowhere near as good as this method. Great vid. I'd love to try this method.

@JTM_djg 9 лет назад

Awesome video! Been playing with SDR# with a RTL-SDR stick. I should try this. I live right in Maine, few hours away from Cutler though. :P

@tecspa 9 лет назад

Seus videos são ótimos! Sempre acompanho seu canal, sou ham radio operator e uso o SDR e acho que um passo para o futuro dos ham radio operators.

@TerryMcKean 9 лет назад

Thank you for sharing this. :) It would be interesting to check other CDs recorded in Europe to see if they too have radio transmissions piggy-backing along with the intended program. For my setup I salvaged a pair of degaussing coils from an old 32" Sony TV, arranged them in a crossed-loop and connected them to the line input on my Dell D630 laptop. Works very good. Eventually I will build an impedance matching/amplifier and it will work even better. As-is it gets lots of FSK signals at times, according to propagation conditions. A whole new world to explore. :) :)

@marzsit9833 5 лет назад

interesting to see the range of the jim creek transmitter 50 miles north of me. it's a massive transmitter site with an insanely huge antenna array that zigzags back and forth between 2 mountain ridgetops and 12 steel towers. the array is pointed west, so if you can receive it 3k miles in the opposite direction with a skimpy antenna it must be able to broadcast all the way to southeast asia. 1.2 megawatts of power helps too.

@berightback2323 9 лет назад

This video is so informative and interesting, that I couldn't help logging in to my gmail account just to say thank you very much for making such great video and explaining all the stuff. Also many thanks for those informative links.

@fanniesimard2228 5 лет назад

@wilkes85 9 лет назад

That is very interesting! I didn't know you could do that. It's cool that you could get a signal from the other end of the country... and even Europe if you had a bigger antenna. Also, I find that with some TVs, simply having them turned off doesn't cut all the interference, you have to unplug it. My early 2000s RCA does that, a lot of newer electronics don't seem to be properly shielded.

@thecooldude9999 9 лет назад

This will be a nice extension to my RTLSDR setup.

@EpicLPer 8 лет назад

This is amazing and interesting as hell, I might even try this soon...

@alynicholls3230 5 лет назад

slinky springs make great vlf anntenas, just strech it out and connect wires to either end, if your receiver only needs one wire just connect one end. i have a really small slinky sort of like a "toy" version(i know a toy of a toy, this when slid on a broom handle and held either end with tape and wires attached makes a great scanner antenna you just stretch it out for different wavelengths when the signal is strongest put the tape on the end to hold it.

@xuliangmuzi1424 4 года назад

Hello, I am very interested in your little toy. Can you share your little toy? My mailbox lk68091618@gmail.com, thank you

@soundarthannah 2 года назад

Thank you! I'm going to give this a try. I'm a total newbie so any advice on making this work would be super appreciated.

@MrShiffles 5 лет назад

You got it working so good...nice video!

@fotografm Год назад

OMG ! I bought that record when it came out. Who would ever have guessed it had an embedded CW message. I didn't have a pc with spectrum analyzer and waterfall display back then LOL

@Tocsin-Bang 6 лет назад

My late father was in the Royal Navy, and one of his jobs was testing the now defunct submarine communications transmitter at Rugby.

@theprophet20 7 лет назад

I saw the large antenna array at Rugby when I was passing by in a train there in 1970. Most of it was demolished a few years ago.

@M0UAW_IO83 2 года назад

Fascinating. I wonder how many more albums recorded at 'The Manor' carry similar signals.

@jaybrooks1098 3 года назад

Coolest thing you ever showed.. never knew it was possible

@Trance88 9 лет назад

Wow. This makes you wonder what other albums out there might have some VLF or other hidden interference embedded in it.

@BrentRF 5 лет назад

Thanks for the video! I have built several ELF/VLF receivers but this appears to be much simpler and easy to use. Look forward to seeing more from you. I cannot download the SDRsharp program. Do you know of another spectrum analyzer program that you could recommend?

@CarNRadio1 3 года назад

nice. I did this in 2011 and 2012 as a part of my diploma on the university. I used a low noise amplifier with a 1000x amplification, an external audio card, and a long antenna. I also tried with an underground microphone on a remote location. even tried with the underwater antenna. tried to get elf signal.

@Elfnetdesigns 9 лет назад

The Nevada Test Range @ Groom Lake has a VLF station but it does not transmit continuous. I discovered it while repairing a guitar amplifier for a friend in Las Vegas, it was being picked up by the instruments pickups and amplified. We did manage to track it down to the test range area as far as we could legally go. Sorry if you mentioned this in the past, but what camera do you use to record? I am looking to get a different one for my tech videos (my auto focus took a shit in mine).

@Roxor128 9 лет назад

The anti-aliasing filter certainly does get in the way. My card (okay, chip, given it's on the motherboard) can do 192kHz sampling, but everything above 20kHz is really weak.

@ethancedrik 9 лет назад

I'll try this with my XP laptop which has Realtek HD Audio, I don't know what the sampling rate of the MIC in is but I'll try that. Perhaps this is also why "Line in" is muted by default in windows?

@acf2802 5 лет назад

Thanks for pointing out that fact about Tubular Bells.

@drmosfet 7 лет назад

interesting video, wouldn't a high speed data acquisition device such as an oscilloscope provide a better signal? they have them in card and USB now, connecting to the soft ware you mentioned to it might be a problem those.

@paotagalatibar2978 2 года назад

Thank you for this very wonderful video, I think there are lots of wonderful applications that I might test on what you have shared... with range from 1hz to 48000hz, I may use a frequency generator to send signal to a particular object (resonance frequency), and using loop antenna I might be able to locate certain object vibrating through signal emitted by the frequency generator... maybe worth a try, what do you think boss?

@PhillR22 9 лет назад

This is awesome I have to try this, my computer has 2 sound cards one internal and a external because I upgraded it but the internal still works and the driver is still installed so I wonder if it will make a difference being Realtek and my external is creative and also I wonder if the morse code is on the vinyl version of tubular bells or do you recon it will be too noisy from dust and static etc

@fotografm Год назад

Excellent video ! I will give that a go !

@KarenLopez-in5ih 2 месяца назад

Awesome work...

@dennisjones8991 4 года назад

Just a tidbit of information, at 24Khz, a 1/4 wave element is 1000 feet. So, a half wave dipole is 2000 ft long. Better get a couple of high towers to install it on. And YES, a good ground is essential. If, you can get the antenna at least 1/4 wavelength, you will receive any shortwave signal. Dennis N7TZQ

@jfsimon1981 10 месяцев назад

Interesting thanks a lot Jean-François

@bluemarvel 9 лет назад

Oh my God! That's so awesome :D

@LowBudgetProductions 9 лет назад

I never knew you could use a sound card as a radio!

@MiloGarciaValencia 8 лет назад

How can you conect the rg85 coax to the computer microphone?? Thank you very much!

@bobskie321 7 лет назад

I have a vinyl America - Perspective and I noticed that at the beginning when I drop the needle there is a 23+ KHz tone immediately after the needle drop and the music starts about 3 seconds after the needle drop and the tone is continuous from beginning to end even between songs on both sides until after the last song is over and the tone disappears before the groove spirals rapidly towards the record label. I think it's from the master tape where the vinyl was cut. No idea if pressings from other countries also have this tone. My copy is an original Filipino pressings from 1984. The frequency of the tone slightly fluctuates up and down that matches the rotational speed of vinyl because the hole of vinyl is slightly off center. I can't hear the tone but I'm using an audio editor to see it. CD can't respond above 22 KHz so if your copy is a CD you're out of luck.

@FOHFILMS 9 лет назад

That is SOOO cool! Also, I spy a powermac g4 quicksulver... XD

@RyanSchweitzer77 9 лет назад

I can definitely see how an LCD monitor can interfere with VLF radio reception if it's a cold-cathode-backlit model, the cold cathode tubes & inverter (basically a miniaturized fluorescent lamp) can emanate all kinds of RF interference. But I'd imagine a LED-backlit LCD display would not, correct? And that's quite fascinating about "Tubular Bells"' hidden VLF transmissions of station GBR, I did not know about that! I have that album on vinyl, I wonder if that would be able to carry GBR's signal for decoding--I'd guess it'd have to be a clean, little-played (or ideally unplayed) copy, with a phono cartridge & preamp that can respond well at 16 KHz.

@KRAFTWERK2K6 6 лет назад

I know it. My microphone input just doesn't care :( Anyway. Really cool, dude! Had no idea it was that easy. Nice low-cost way to experiment with an SDR when you don't have a USB dongle that allows you to scan an even bigger range of frequencies.

@Mizar88 8 лет назад

wow, very interesting video! thank you

@evilroda 9 лет назад

You're so awesome! Tell me, what camera do you use for your videos, and how do you get it to record screens so clearly?! :O Also, how would I find out the relevant specs of my sound card?

@vwestlife 9 лет назад

Evil Roda I use a Canon FS200 camcorder. If you Google the name of your sound card or the sound chip it uses, you should find the specs.

@lambdaprog 9 лет назад

It looks like you're having some transient noise. You can try the Noise Blanker to reduce it. The noise reduction may help also.

@KC9CPX 4 года назад

I use a shortwave radio receiver with the onboard whip antenna tuned down all the way to 150 kHz where it’s quietest in terms of interference.

@JoshuasRecordings 9 лет назад

My sound card has a 96KHz/24-bit DAC, I wonder what I could pick up!?

@CARLiCON 6 лет назад

Great video VW! Does anyone know what studio device was actually picking up the radio signals? I had an old guitar amplifier that would randomly pick up commercial am radio at certain times of the day (probably bad input filtering, or a grounding problem) but the article I read about TB stated that they recorded the guitar & bass directly into the console. It's strange that the engineers would not have heard this as they were listening to the isolated tracks on the master tape. This must have been discovered before someone isolated it in SDR.

@fungo6631 2 года назад

Or maybe they were very much aware of it and left it in on purpose as an easter egg.

@BodyKnight 9 лет назад

This was a great video.

@Halterung01 9 лет назад

That is really cool. Would it be possible to get a USB receiver (maybe a DVB-T dongle) and using it with SDR Sharp? And could one possible even record all radio that is being transmitted in that time into one single WAV file? That would be simply awesome.

@debbiramsey4603 4 года назад

Excellent educational

@miuziqa 9 лет назад

Fascinating!

@tf2whackyengineer 9 лет назад

First, I learn about Rush's YYZ and now this. This is cool.

@sir_john_hammond 6 лет назад

what about YYZ?

@cdadlpop 6 лет назад

Intro is YYZ in morse code

@cdadlpop 6 лет назад

You know about Kraftwerk?

@sir_john_hammond 6 лет назад

I listen to Kraftwerk at least once a week.

@MercedesCitarobusvideos 9 лет назад

I downloaded a mp4 version of this, but it didn't contain the morse code at 16.100

@demonicsweaters 7 лет назад

wow, really interesting

@BenjaminSteber 3 года назад

"Don't do this during a thunder storm" But you'll miss the whistlers!

@coolelectronics1759 9 лет назад

Wow this is very cool wonder if it would be possible to emulate an FM or AM radio receiver or transmitter on the computer I don't think a transmitter would be possible but possibly a receiver using only the sound cards analog input and a piece of software

@Gameboygenius 9 лет назад

Cool. I need to try this.

@SproutyPottedPlant 9 лет назад

That's really cool especially that there is no radio needed!

@forestsandman 9 лет назад

Very cool!

@roogalater 8 лет назад

I had no idea about the hidden 16khz signal on 'Tubular Bells'. Amazing, thanks for that. If you got a miniwhip antenna outside, you'd be amazed how much the noise floor drops and the signals come up. They're easy to make. It actually works from DC up, not 10khz up. dl1dbc.net/SAQ/Mwhip/Article_pa0rdt-Mini-Whip_English.pdf

@randygray3291 3 года назад

How low on the spectrum can you broadcast voice/music? And is the Antenna required too large or can it be done at close range with a shorter antenna?

@vwestlife 3 года назад

Voice transmissions are certainly possible in the VLF range, although that's not an efficient use of the bandwidth available. Shorter antennas are possible but won't give as good of reception (or signal coverage if transmitting).

@bobskie321 9 лет назад

I noticed that if I use a cheap poorly shielded RCA cable to amplifier's line in without connecting the other end to anything I can hear a faint sound from our local AM stations.

@stevenchiverton48 5 лет назад

very interesting but looks like your using an old pc flatt tower with a different audio plug than mine which is just a basic small headphone socket can i use that and is that program suitable for windows ten

@vwestlife 5 лет назад

If your computer has only a single headset jack (for headphones with microphone attached), you may be able to do this with an appropriate wiring adapter.

@TRUEiMPROrecords 4 года назад

WOW thanks! Iúse these sounds in my music :)

@Exceedvictory 2 года назад

Hi first time here. And I have a question, if I may? I have a person using vlf or vhf to hear my thoughts or slight throat movements and I need to combat this. These people are very bad people and I have to assure my family is safe I believe there are pinhole cameras in my house also. And I can hear them complain when ever I think about going to the D.A.s office Or contacting the Department of justice. These people have a thing for watching people 24 hours a day. It breaks every god given right I know of. Any help or input would be greatly appreciated. Thanks

@LOLZpersonok 7 лет назад

Have you been able to pick up any numbers stations or otherwise strange radio broadcasts in this way or a similar way?

@vwestlife 7 лет назад

No, numbers stations operate on shortwave (HF), which is well above the frequency range of VLF or LF.

@LOLZpersonok 7 лет назад

I see, I thought shortwave was within the VLF frequency range. Have you ever picked any numbers stations up on your shortwave radios before? I wouldn't have any hope of ever finding any in my area.

@vwestlife 7 лет назад

LOLZpersonok Yes, Cuba still uses numbers stations a lot and I can hear them quite often on shortwave.

@AdamEbelgccengineering 9 лет назад

I am a little confused. Did you use a long wire antenna outside when you received these signals? I also see that you used a AM loop antenna that is connected to the sound card. How did you hook this up? I was trying think on how you did it, but still it got me confused, and I really need a good indoor VLF antenna for my SDR. Please help me out. Thanks.

@vwestlife 9 лет назад

I used a combination of both the loop antenna and outdoor longwire antenna (although it's not really that long, only about 20 feet).

@jimhenry1262 6 лет назад

Can a person use this apparatus to detect weaponized infrasonic pulse generators?

@jimdayton8837 9 лет назад

Sounds really cool! I don't have an antenna though...

@Llamarama100 8 лет назад

I wonder if any other albums have such an audio artefact... Presumably many

@batfalcononyoutube 3 года назад

UNBELEIVABLE!!!

@raycarpenter8459 3 года назад

great video just watched it, i think some of these folks use copper rods in the ground for antenna's

@abdula4256 4 года назад

Thank you for this video i like it Best 73s from A71BR abdul

@tanyalove6983 2 месяца назад

Hi y'all. I was wondering if I can use the sound card in my android phone any ideas? I think sharp++ works on the phone any idea how you can use the sound card 💋 and hugs

@hamzah6251 4 года назад

Amazing

@Ninnuam999 7 лет назад

For everyone interested in this there's a website to listen to some of these signals "websdr", without the need to use an antenna.

@Ninnuam999 7 лет назад

Yes, you're right but if someone does not have the equipment this would work to see how it sounds.

@sonus289 2 года назад

Wonder how many other albums have been done at that studio that had the same issue

@vwestlife 2 года назад

Many, many recordings have a 15.75 kHz tone in the audio due to someone using a CRT monitor or TV in the same room as the recording studio.

@shiloranxxer 2 года назад

What if you buy the most expensive 2 mHz sampling rate sound card just to listen to am radio.

@MarkPentler 5 лет назад

How do you actually connect the antenna to the mic input? What pin is the wire connected to? If I get a stereo lead with a minijack on the end and cut it down so I just have the two cables coming out, should I connect my antenna to that? But which core? None of the explanations of this method online address this in any great detail :(

@vwestlife 5 лет назад

You connect it to the wire that goes to the tip of the plug. You may need to use a multimeter to find one which one that is. Or just try both and find out which one gives better reception.

@MarkPentler 5 лет назад

VWestlife thanks, I have access to one so I can tone the lines.

@MarkPentler 5 лет назад

VWestlife do I need to connect a ground anywhere? To the ground I guess (sleeve?)

@Tassie-Devil Месяц назад

Seemed like a good idea... but the software doesn't work for me. I downloaded the SDR software, then tried to run the EXE... but it told me I have to install ".NET Desktop Runtime" I downloaded this... tried again... I still get the same message. SDR package refuses to initiate. Might be some incompatibility issue with WIN-10?

@catalinalb1722 4 года назад

Would you be able to receive DCF77 ? that would be awesome. I live at about 30 km south from the DCF77 clock station.

2 года назад

Yes, i tested it with my sound chip. However, your card has to have a sample rate of 192khz or higher. You should also have a wire of at least 2 meters.

@DoodiePunk Год назад

Wow! I'd like to have a super wide sound card to receive the mediumwave range! 🤓

@directedbypuma 8 лет назад

Tutorial please? because it looks like you are playing a wave file and not capturing what's coming from the mic jack or input. Does audio have to be recorded first then played back in SDR#?

@vwestlife 8 лет назад

No, you can do it live. This site has some basic info on setting up and using SDR Sharp: sites.google.com/site/g4zfqradio/connecting-soundcard-sdr-to-computer

@puma9354 8 лет назад

+vwestlife hmm it doesn't explain what you're doing with a lead in the audio in. Also you're frequency graph shows frequencies higher then. What you would see if you're using you're sound card as input as like someone said here the graph only goes to 20khz when selecting sound card as input. It would be great if you showed us this with sound card as source, doing it live.

@vwestlife 8 лет назад

***** You have to make sure your sound card supports and is correctly configured to a 96 kHz (or higher) sampling rate for recording. There should be an option in the sound card's settings somewhere. And there are other videos on RU-vid about using a sound card to receive VLF signals, they may have more detailed info.

@directedbypuma 8 лет назад

+vwestlife Okay thanks I will play around with it, I see that when you raise the sampling rate of the sound device in SDR# it does change the scale of freq. chart. I do see the waveform dropping down a little after 24Khz but thats becuase I didnt change my sound card settings, I will play with it some more. I've been catching up on all things RF and I find this pretty interesting. I'd like to see examples of how this method can pick up communications devices would use and possibly decode it.

@you2ber252 8 лет назад

With this software I discovered that the realtek audio chip of my mothrerboard has a bandpass filter that filters the mic input to 20kHz no matter how high is the sampling frequency. Even with sampling rate of 192kHz, over 20 kHz or so, no signal passes through. So I'mm wondering what is supposed to be the purpose of having the capability to sample at 192kHz, if there's a fixed banpass filter at 20kHz in the input. Bah....

@s4ndwichMakeR 8 лет назад

Tried the line-in?

@sir_john_hammond 6 лет назад

use another soundcard, then. this principle should even work with external usb units, I would imagine...

@paaao 5 лет назад

This is because the human ear doesn’t process or hear audio above about 18 khz, so anything above 20 khz is basically un-wanted noise in most cases. Buy an external sound card used for recording/processing music, and you should be able to sample above the 20 khz cut off

@Kennynva 6 лет назад

I see that you have "IQ file (*.wav)" selected as your source, instead of a SDR radio, at the top left..which means you are playing an already recorded radio audio file..I believe I am right..

@vwestlife 6 лет назад

Yes.