SDRAngel Rx & Tx

Has anyone tried SDRAngel and had success with Tx ?

Does it use a microphone or ?

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Probably help to have a link to the repository …

I found 2 git repository’s … hope this is the right one (recent)

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Mike,

I have mine compiled and running for transmit and tried hunting for the transmit signal from all 4 transmit ports…I’m pretty sure I still don’t have settings running right yet in SSB, but if you believe the modulator waterfall or the NBFM modulation meter in either of those modes, the front panel mic jack and the selection you make in the PREFERENCES—>Audio menu item will allow you to choose your microphone audio source (even from ALSA). I chose the native Intel resources from the audio selection menu and then spoke into my gaming mic (and I’m no gamer here - it’s just a good mic for this kind of thing) and it does modulate in the app. Now I have to find out why I’m not getting a transmit signal, but Edouard has sent me the same link you have and I REALLY need to read it. I’m determined this afternoon to make this work because at 4:00 AM tomorrow I head for Dayton and I’d really like to know if the Lime will work with this app. I have a notion that it’s a cockpit error on my part and by reading Edouard’s link I’ll know more how to get transmit REALLY working by tonight…then I need to crash for the 7-hour drive to Dayton.

Exciting times - - I think this app has the potential to be ‘the one’ for everyone to use on the Lime…So far it’s the one that has the most traction in transmit…Stay tuned…

73 de Marty, KN0CK

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The author needs to seperate the gain controls…

Most times i get no signals

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Mike,

Yep…

Hello,

I have no problems getting signals at ~50 dB gain and get occasionally overloaded for values above. So far my usage is mainly on UHF but on HF this may be a different story and the default LNA-TIA-PGA settings built in the LimeSuite global gain function could not be quite right. There is no off the shelf API in LimeSuite for separate gains so this needs a little bit of work with the underlying LMS7002M layer but is probably feasible. I thought of it but left it for later. Next version will focus on some global GUI reworks and remote Tx support coupled with a new version of SDRdaemon so this could be postponed to the version after.

Best regards,
Edouard.

Edit: well the separate gain functions are already there they are just unused and therefore untested. So it is a matter of updating the GUI and debugging (still some work…)

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ok … id also say … that you could simply change LNA gain for around 107Mhz down, for a setting of 3db (in gqrx).

That’s where i usually have mine set at for 6M(53Mhz) down to AM bands …

Issue opened on Github repo: https://github.com/f4exb/sdrangel/issues/32

I have a problem withSDRangel that would make it hard to use as a transceiver. I was listening to a scanner to find frequencies to tune to and found out that there is more than a second of latency between the RF and the audio at the speakers. If this went both directions it would be annoying to use for normal conversation. I assume this is because of buffering.

I assume your running Ubuntu ?

Have you tried setting the audio system to real time ?

It is the same on win10 but I am happy to hear any TX from Lime :wink:
Must try on Ubuntu 17.04 too

I run debian stable/backports. For security reasons, mostly. I can keep it up to date across releases that way, too. I will look into what I need to do to get real time. I could always roll my own distro if I have to. Today and tomorrow I build a deck on a house.

@Axeman,

Edouard (F4EXB) has mentioned that there is a lot of buffering in the current version of the software and that subsequent versions will be better - so some of that is forthcoming…Stay tuned…

73 de Marty, KN0CK

My TX test run of approx 20 min AM on 435 MHz on 1/4 lambda stick went well.
HW 40 C steady temperature on hot day - main target to know that my installation
is safe on longer run.
SDR Anglel & Lime have no clue about CW, but even that dot and dash mishmash
was good enough for testing. Win10 version is not stable, TX going out so who cares :wink:
Signal range was approx 100 m…
73
Djani

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Cool, 100m is really cool! Did the Lime get too hot?

No.
Max temperature, measured with Lime Suite was 40 C (20 min AM TX)
(On longer RX session temp goes 37-38C)
But my Lime have cooler on two major chips and box is die cast Al
with internal and external active fan cooling & some members here are
joking that my setup is about to fly away :smiley:
73
Djani

Ubuntu 17.04 & SDRAngel ?
Anyone managed that, yet?
If yes, small “how to” much appreciated…
Already have Lime Suite and Cubic SDR running on Ubuntu 17.04

Oh, around 40ºC with active cooling. I’m just thinking of installing a heatsink.

Hello,

I’m afraid the buffering is not going to change a lot. With standard PCs and not real time OSes you do need a lot of buffering to absorb the effective rate changes on the USB bus and the CPU. While it can overall sustain the rate it is not at all regular in the details. If you want to reduce buffering and thus latency you have to use a complete different setup with FPGAs and direct access to the data bus of the LMS7002. I think all Tx SDR software that run on commodity hardware and desktop type OSes face this problem or they lie to you.

Another point: I am confident on my dot and dashes but if you use large sampling rates like the maximum of 30 MS/s as I saw on some screenshots (that was Rx and I am already amazed that it works) then packet drops can occur which completely ruins the code you are trying to send. If it was voice you would notice a lot of hickups. Bear in mind that you need such high rates only if your baseband signal requires it which would be the case if you were trying to send WiFi signals for example and SDRangel does not do that. At its very maximum 13.5 MS/s would be required to send an ATV signal at 30 FPS 625 lines and 720 pixels per line.

The Lime has the great feature of hardware upsampling up to 32 times so you don’t need to push it hard on the sampling rate on the software side to get a clean signal. I usually never go above ~5MS/s. I noticed on the Rx side that you cannot get lower than 2.8 MS/s without having libusb warning messages so around 3 MS/s would be fine for most usages.

BTW my Lime is stable at ~50C without active cooling. I mean just heatsinks and an aluminium case, no fans.

Best regards,
Edouard.

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Tnx for clarification…
I am curious are you running your SDRAngel SW on Win or Linux and which one?
73
Djani