Multiple streams from one SDR

[colin]

This post is to pick up the discussion that started in the Streaming DFES Audio Announcement.

Yorky, to the surprise of both of us, this was achieved simply, and on windows! Having said that, I do want to get it working on Linux....

As you and Gavin are both interested, I thought I'd post my story here.

The first step in getting multiple streams was having the right software. I changed from SDR# to SDR Radio. As Simon (the developer) says, "It's all about the software".

SDR Radio supports multiple VFO's natively. This means that I am still only running one (RTL2832U + R820T Mini DVB-T Dongle). I initially had some audio issues, as the hardware that I have is underspec. (Not to mention, no local display - cracked LCD and VGA port not working, faulty RAM module) I have had to wind the bandwidth of the radio back from the 3MHz that it is capable of monitoring to only 2 MHz. My intention is to monitor as many of the local DFES frequencies as I can, including simplex. So new hardware required. I know I can get Northam (surprise) and I can get some of Toodyay. I haven't tried York or Mundaring. York is more likely, due to my location. Simplex - Well, lets see what I can get.

I currently use a notebook (Currently Win 10 64 bit), so if the power fails, I still have a local recording.

[yorky]

Thanks for post Colin, I smell a holiday project!

[colin]

Now I need some time to sort out splitting the audio.
Northam on left, Simplex on right of Northam feed
Toodyay on left, Air-Ops on right of Toodyay feed.

and when it is all really quiet, everything together (Winter mode?)

[yorky]

I had a play of this on the weekend and got some good results.

SDR Radio Console is certainly a powerful tool, it looks user friendly but take a few hours to get your head around what happens when you press certain buttons.

I've managed to get three VFO's running at the same time without much issue (three different bus channels), and even tested streaming them out successfully. Limiting factor is my crappy Internet as usual.

A few things I'm still personally in need of doing:
1. Ability to remotely control the frequencies/VFO's via mobile (can already do it with windows only client but no good if out).
2. Be able to record and record only transmissions (can already record but just continuous).
2a. After recording, be able to playback on mobile (can be done if using Broadcastify but it's tedious and basically useless).
3. Use multiple RTL dongles as I'd want to monitor, record, and view around 3 different lots of bandwidth. I think that can already be done with multiple instances of SDR Radio Console and extra VB Audio Virtual Cable's but I only have one dongle at present.

Then we could make a list of what should be publicly streamed as well?

[colin]

Team viewer has an Android client, and is free for non commercial use.

[yorky]

Thanks Colin yes good idea.

I also just had a look at Audacity and that has the option to record only when sound active but that's going to be one big file that you'd have to manually save.

[colin]

There is another free product that I use to "auto-play" the radio.

AutoHotkey. I use this to start SDRConsole from the windows startup folder, rather than putting SDRConsle directly into the startup folder. Then at the right time I press the "Play" button. WooHoo. Fully automated Stream, even if the pc restarts!!!!

You may be able to use this to break audio files into chunks.

[colin]

Oh, and VAC Virtual Audio Cable, pipe audio from one app to another, or two, or three...
I had to by this one, but we'll worth it for the stream.

[yorky]

That was another question I was going to raise, I couldn't find a way to auto start the radio when you open SDRConsole. I was assuming the Server service might do that but wasn't sure?

Yes I could use something like that to periodically stop, save and start recording again but I'm still on the lookout for a good program to save transmissions only.

Yes I'm using http://vb-audio.pagesperso-orange.fr/Cable/index.htm which gives you one for free, extra 2 donationware.

[yogibear88]

Hi,
I am setting up a SDR running off a raspberry pi and i was wondering what is a good antenna to use that will help me pick up DFES streams and also i might use it to decode the pager messages.

[yorky]

If you are in a good high location any good antenna will do. Do you have anything at the moment or need to buy one? Just look for a VHF antenna mainly for those services.

[yogibear88]

I am just waiting for some of the hardware to arrive from china. Once that has arrived i will work out an adapter to connect an antenna to the DVB dongle.

[colin]

For my SDR that is providing my feeds, I am using a scanner aerial purchased from Mobile 1 some 10 years ago. I had to re-locate it earlier this year, and noticed that it is in pretty poor condition.

I am using an MCX to BNC pigtail and a 150mm USB extension lead to ensure minimum pressure on the USB port in the PC.