== MANUAL  == WSPR call: PH4RTM == 2mtr WebSDR ==
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Allow keyboard:
j k ← →: freq down/up (+shift or +ctrl/alt)
b B: band up/down
u l c a f: USB, LSB, CW, AM, FM
z Z: center/zoom waterfall
g: enter frequency
m: toggle mute
s: toggle squelch
n: toggle notch

 80m:  60m:  40m:  30m:  20m:


? dBm   peak: ? dBm


  === WebSDR Maasbree ===

Signal strength plot:


Or tune by clicking/dragging/scrollwheel on frequency scale.

Or use scroll wheel and dragging on waterfall.


  ?  kHz@-6dB   Pitch: ? ?  Hz
Or drag the passband edges on the frequency scale.

This WebSDR is currently being used by ? user(s) simultaneously:      compact view


WebSDR === Maasbree === operating on 80m, 60m, 40m, 30m and 20m band (offline during local thunderstorms)

Sysop messages:
• June 20: Now using dynamic DNS:
• Dec. 11: Keyboard shortcuts: added the keys m, s and n for toggling the mute, squelch and notch. See also: Manual WebSDR Maasbree
• Dec. 18: Update Firefox: version 84.0 now behaves like Chrome and Edge: frequency scrolling on the frequency scale needs the shift key to prevent page scrolling.
• Dec. 19: Problem with Firefox update solved. Chrome, Edge and Firefox don't need the shift key anymore for frequency scrolling on the frequency scale.
Solved it in cooparation with Bas ON5HB and Clint KA7OEI (Utah WebSDR) and by looking in the code of the WebSDR Twente.
• Jan. 19: The waterfall brightness is equalized over all bands (no change in S-meter reading).
On 80m/40m/20m (RSP1a receivers): noise shaping now lowers the quantization noise by 8dB (was 4dB). The noise shaped outside the band is masked.
• April 15: Running WSPR on 80m, 40m and 20m using the call PH4RTM (see Manual).
Thanks Bas ON5HB for the cooperation and especially PA3FWM for making it possible with the WebSDR software.
• June 7: 144MHz-145MHz part of the 2m band Maasbree WebSDR now has a horizontal polarized big wheel antenna == 2mtr Maasbree WebSDR ==
• Aug. 8: For accurate WSPR SNR measurements see: == WSPR ==
• Sept. 29: The up and down 10Hz buttons are replace by an UP and DWN button for better support of tablets and phones.
By a short click on a button still a 10Hz step is made up or dwn.
When keeping the button pressed the frequency changes with increasing stepsize.
• Dec. 3: Exploited noise shaping further.
On 80m the quantization noise is reduced by 11dB. On 40m and 20m it is reduced by 18dB.
As a result the effective number of bits to the websdr is now 9.83 bit on 80m. On 40m and 20m 11 bit.
20m now runs on 1024kHz enabling a 460kHz bandwidth for full coverage of the band. We are testing 1024kHz for stable operation.
See also the updated: Manual WebSDR Maasbree

For more info goto: background and technical info, FAQ and Downloads

Operators are Loek PE0MJX and Jan PA0SIM.
It is located in Maasbree JO31AI (QTH PH4RTM), intended as an alternative for HAMs having a high local man-made noise level.
The Maasbree location is quiet with on 20m a better than rural noise level. With now and then a weak local noise source.
Koos PA0KDF has done measurements with calibrated equipment and antennas: IEEE article
Receivers: three SDRplay RSP1a receivers for the 80m/40m/20m bands and two FiFi SDR receivers with sound cards for the 60m/30m band.
Antenna: a small broadband active loop antenna: Active broadband loop antenna
Gain in the WebSDR is set for an equivalent antenna factor AF=0.35 on all bands.

Note 1 Firefox is the preferred browser.
Code from the Utah WebSDR (tks!) is added for support of Chrome, Apple, etc. Go to this Utah site for more info if needed.
Note 2 If you have a mobile phone, try this one: ==> Mobile version <==
Note 3 CATSync allows you to synchronize the WebSDR with your real rig.

Frequency can be set by:
- Preset buttons
- Clicking/dragging/scrollwheel on frequency scale
- Direct input in frequency field
- Fine tuning in +/-10Hz steps (or select up or down 10Hz button and use enter key or spacebar)
- Keyboard shortcuts !
- Band selection buttons
- Memories
- Click on memory labels in waterfall
- Bookmarks e.g.: http://www.websdrmaasbree.nl/?tune=3558cw
- CATSync and your own transceiver

CW pitch can be set by e.g. the shift buttons.

Keyboard shortcuts (tick Allow keyboard):
j k ← →: freq down/up (+shift or +ctrl/alt)
b B: band up/down
u l c a f: USB/LSB/CW/AM/FM
z Z: center/zoom waterfall
g: enter frequency
m, s, n: toggle mute, squelch, notch

WebSDR is a very strong concept developed by PA3FWM!
More information about the WebSDR project can be found on http://www.websdr.org.

© Copyrights Graphical User Interface (GUI) design of this WebSDR: PA0SIM and PE0MJX
Copying the GUI design partially or completely is allowed with proper source reference including a link to this WebSDR for non commercial WebSDR use only.