MANUAL HF-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





? dBm   peak: ? dBm


  == 2m 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


2m WebSDR === Maasbree === (offline during local thunderstorms)

Sysop messages:
- June 2021: The vertical antenna is replaced by a horizontal antenna, the "Big Wheel".

The 2m WebSDR is located in Maasbree JO31AI (QTH PH4RTM).
It is operated by PH4RTM, PA0SIM and PE0MJX
Receivers: two SDRplay RSP1a for low:144MHz-145MHz and for high:145MHz-146MHz.
The WebSDR software runs on a Raspberry Pi4 (less than 15Watt in total).
Antenna for high (145MHz-146MHz): vertical Diamond300
The low (144MHz-145MHz) receiver is from June 2d 2021 connected to a Big Wheel horizontal antenna.

See also the HF websdr in Maasbree on port 8901, HF WebSDR
For technical details about the websdr's see Details

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.
Chrome users: use +Shift key for frequency scrolling on frequency scale in waterfall.
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.:
- 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

WebSDR is a very strong concept developed by PA3FWM!
More information about the WebSDR project can be found on

© 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.