MHV Radio (WebSDR or alternative running at MHV)

Please do suggest a better name for this project.

We lack an online amateur radio receiver in Canberra. In fact, sometimes there aren’t any in Australia at all: [1]. This would be a valuable contribution to the amateur radio community, such as QRP (low-power) HF users like myself who would like to sanity-check their setups prior to attempting SOTAs [2].

The main problem is that WebSDR is not free software. One must request and then be offered the binaries to download and run.

Some alternatives:

Sadly, MHV mightn’t be the best location. It will require filtering due to extensive nearby noise sources. Also, HF antennas are insanely large beasts as far as antennas go, but we should be able to get something of value up. Even if it’s stringing something across from the flagpole…

… plus, there’s always the UHF/VHF repeater traffic, which we should definitely also include.


Hi Paul,

Just for qrp signal checking, I have a couple of Android apps, sdr touch and rf analyser. Don’t know if they are available in the iPad world


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Looking at HF noise today, thanks to Carlos VK2TY demonstrating the PR100 [1] with HE300HF [2] directional-ish loop antenna to @Dexta_Bb:


  1. It’s the 20mA RS485 current loop serial signal on the coloured strip lighting radiating much of the noise - seems to be chattering constantly
  2. Followed by the 13MHz RFID signal, very strong, would normally be ok but ours is spewing spurious emissions allllllll the way up and down the band. A bandpass filter would help a lot!
  3. The laserjet is noisy! Need to keep it off.
  4. The 3D printers are noisy when printing.
  5. Computers & LAN cables are noisy…

We could resolve items 1-3 by just making the space probe turn it all off so it’s at least quiet when space is closed.


Hi Paul,

I found the parts I was using to build my “el cheapo” crossed loop HF receive antenna, so I’ll bring that to the space for you to take a look. It looks fantastic and really easy to replicate.

The RF amplifiers I’m considering have 2N2222A as core elements, I opted not to get fancy amplifiers yet. Parts should be arriving from China soon.

I think I have found the boxes where the external USB sound blaster module lives. I’ll bring that to the space as well to see if you can find some drivers to make it work under linux. It is the “companion” of the elektor SDR receiver I gave you the other day.


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Excellent. Hey @jjiaoyuwang did you end up doing anything with those Core2 PCs? New PC's for MHV :smiley:

I have a potential donor laptop at home I could use but would be good to keep it free for something else I had in mind

Hi Paul,

I’ve brought them to the makerspace and to my knowledge, no one is using them for anything yet. The PC’s are under the table where we were planning to stash the reprap. Go ahead and hack em!


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