G8JNJ

Some interesting enhancements to OpenWeb RX by Jakob, DD5JFK which he seems to have forked from the original work by Andr?s, HA7ILM.

https://github.com/jketterl/openwebrx/blob/develop/README.md


Apart from the addition of wsjt-x based demodulators for FT8, FT4, WSPR, JT65, JT9

He's also added Clientside bookmarks (DX Labels or Tags) which every user can store for themselves in the browser's localStorage.

Interesting stuff.

Regards,

Martin - G8JNJ

Hi Jim,

>
>Wasn't extension locking added recently
>

Yes it was, but the dev extension is not listed among the rest on the extension admin page, so you can't lock it out from general users.

Regards,

Martin - G8JNJ

Hi All,

Over on Simon Brown's SDR radio IO Group, he's just mentioned the Voice Activity Detection (VAD) component of Rnnoise, and thinks that it may be worthy of further investigation.

https://people.xiph.org/~jm/demo/rnnoise/

It's written in C and is available under a BSD license, and uses Recurrent neural networks (RNN) to provide voice detection and noise suppression.

Regards,

Martin - G8JNJ

HI,

It's possible to use an external 12v supply.

However adding a 1000uF 16v electrolytic across the secondary of the big common mode choke in the "Biasing Tee" removes just about all of the unwanted noise around 60 & 120KHz emanating from the DC-DC switcher.

I think it was an oversight on their part to not include something like this.

Regards,

Martin - G8JNJ

Hi All,

Well the MLA-30 'sort of works' and it doesn't cost very much, so it's better than nothing for folks who don't want to build their own.

You get quite a bit for your money, and it's OK for use with say and RTL dongle in direct sampling mode, but I'll probably cry the first time I see one being used with a high end receiver like a Perseus or Airspy HF :-(

Here are some measured parameters of various popular loops using the same test setup.

MLA-30 OIP2 approx +46dBm OIP3 approx +20dBm
M0AYF OIP2 approx +75dBm OIP3 approx +27dBm
Wellgood (Copy of early Wellbrook) OIP2 approx +57dBm OIP3 approx +37dBm
LZ1AQ OIP2 approx +79dBm OIP3 approx +36dBm

I've now added the MLA-30 information, including circuit diagrams to my Active antennas webpage.

https://www.g8jnj.net/activeantennas.htm#MLA30

Regards,

Martin - G8JNJ