VERON Amateur radio club ETGD
PI4THT
Faculty for Electrical Engineering, Mathematics and Computer Science UT
Wide-band WebSDR

On this page you can listen to and control a short-wave receiver located at the amateur radio club ETGD at the University of Twente. In contrast to other web-controlled receivers, this receiver can be tuned by multiple users simultaneously, thanks to the use of Software-Defined Radio.

This site, which in 2008 was the very first WebSDR site ever, was finally reactivated in July 2012 after an interruption of more than 1.5 years; read also the old news since then.


[picture of the SDR hardware] The system is currently composed of a "Mini-Whip" antenna, a homebuilt SDR board (as pictured; see here for background) which samples the entire shortwave spectrum and sends all of this via a gigabit ethernet link to a PC, where a special version of the WebSDR server software processes it. The Mini-Whip is based on a design from PA0RDT (google finds it); see some pictures. The active receiving element is about 5 by 10 cm large. Such an antenna only works well with a good grounding; ours is on top of a 20m high building, the upper part of which is all metal.
Other services available on this system:
WSPR reception
Chirp signal reception
Entire day waterfall display

Questions and remarks about this WebSDR can be sent to the developer and maintainer: pa3fwm@websdr.org (but please check the FAQ first).

Please log in by typing your name or callsign here (it will be saved for later visits in a cookie):
It seems you are using a mobile device; click here to switch to the mobile version of this site.

View: waterfallblind
Allow keyboard:
j k ← →freq. down/up (+shift/ctrl/alt faster)
u l c a fUSB, LSB, CW, AM, FM
W wfilter wider/narrower
z Z ^Zcenter/zoom waterfall
genter frequency
m V vmute, volume up/down
t TVFOs: toggle A/B, set A=B

testtest

kHz   
Volume: mute
Filter: 2.40 kHz
squelch autonotch noise reduction

Audio recording
 


[scale]
 -99.9 dBm; peak  -99.5 dBm
Waterfall zoom






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View:
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Brightness:

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[trashcan]
This WebSDR is currently being used by 156 user(s) simultaneously:      compact view

anon25294
klaas
anon61120
ODIN-2
Hmmingwaves
PA3FWM
Oracle
BosniakBro
mobile/Android
anon32850
Hyran
ITube
anon00363
anon08362
anon16973
anon62442
anon09955
anon11640
anon06902
anon04855
mobile/iOS
Skykanggg
lw82
anon63322
anon21713
anon27450
anon44883
notx
EAM.WATCH-BOT-4724
aspencade
Lux
anon29685
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
Lux
anon07745
mobile/Android
anon16597
anon32850
anon46484
anon60103
Gali
anon51140
anon62445
anon59487
anon47354
anon43995
anon24162
EAM.WATCH-BOT-11175
anon46222
Ice
Ice
Ice
Ice
Ice
Ice
Ice
Ice
mobile/Android
RED ORCHESTRA
anon08288
ex RV6LMT
anon41410
anon16283
anon00728
anon23140
mobile/Android
Pierce
anon52716
anon19643
anon18465
anon02732
Fixy Clary
David visser
anon53937
anon02802
anon09527
anon44293
TheFlaminFire
anon58490
anon14024
anon19782
anon41609
anon33811
evert
anon50923
fido
anon48028
anon43758
anon19779
anon45934
Chris
anon37516
anon49365
mobile/iOS
anon06980
egrg
anon08296
Silanty
mobile/iOS
anon04420
anon40249
mobile/iOS
anon29161
anon63476
anon03710
anon58155
cc
anon32850
anon32850
anon32850
jellybelly
anon32850
anon37712
intercity
anon41609
Asrob1001
anon32850
anon50953
anon48028
gemma
mobile/iOS
anon48028
PutYourNameHere
anon17440
anon04172
N9NLU
anon07671
anon25294
K0VZ
anon25294
anon25294
anon25294
anon25294
anon11310
Signalman

Chatbox:
This chatbox is intended to discuss the operation of the WebSDR. Please keep the discussion civil and polite; that also means no swearing ("four-letter words").
The operators of this site disclaim any responsibility for text appearing in this chatbox.

2256z Chris: 7000 LSB Our indonesian friends are waking up (Jakarta SDR)
2256z ITube: For broadcast stations use am and if there is a label just click it
2258z lw82: well, idk but some times the site bugs for me and i only can fix if i reload, i did, i clicked on it, and now its working pretty nice
2258z ITube: Using chrome browser?
2301z Chris: 11720 AM Morning from Vietnam
2302z lw82: yeah im on chrome
2304z ITube: For several months there's a bug in chromium based browsers including opera. So better use firefox or edge
2307z John SWL: iceland radio now sounding latin, 207AMsync
2319z PutYourNameHere: jbjhgfdfgihknju
2320z ITube: Sri, not my language :)
2325z PutYourNameHere: neither mine :)
2329z ITube: Watching 3346am for hours - any idea?
2332z TheFlaminFire: btw HAARP is on right now on 4190khz
2333z TheFlaminFire: 4190cw HAARP
2333z ITube: Thanks for the info TFF
2335z PutYourNameHere: :O
2336z TheFlaminFire: Info on HAARP can be found here https://twitter.com/ctfallen/status/1068285084199841792
2336z TheFlaminFire: that twitter account
2339z Skykanggg: Skykanggg signing on
2341z TheFlaminFire: Skykings can wait, HAARP is where its at

Please type a name or callsign in the box at the top of the page to identify your chat messages! Please keep in mind this chatbox is shared with often hundreds of users; don't use it for chatter; use it ONLY for messages about the operation and use of this WebSDR, and about the signals received with it.

Please calculate 5+2 =

Logbook:
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Comments, if any:
Note: time, frequency, your name/call, and DXCC information are added automatically.

View the last 100 lines of the logbook, or the entire logbook (ctrl-click for new tab/window).
Station information:
Lookup in databases:


Advanced settings - only change these if you know what you're doing
Noise reduction level: automatic manual
Squelchlevel:
Audio out: left both right

Gain control: automatic manual limit
Hang time:
Gain:
Waterfall:JavaHTML5   
Sound:  JavaHTML5

Statistics:
Past 10 seconds: CPUload=75.0%(2.5%+20.8%+46.4%), GPUload=55.1%, 155.29 users; audio 11139.4 kb/s, waterfall 2882.5 kb/s, http 659.9 kb/s

WebSDR HTML5 sound - Copyright 2007-2018, P.T. de Boer, pa3fwm@websdr.org