STEMlab 122.88-16 SDR

[DH1KLM]

Neues STEMlab in Sicht.
https://www.redpitaya.com/n86/new-stemlab-sdr

[df5fh]

Hi dear Red Pitaya fans,
and hi Pavel, what is your opignion regarding the new device ? I expect that it will dure some time until your great software packages are available for the new machine ? I hope I was not too blue-eyed to pre-order one exemplar at redpitaya.com

Vy 73
Henning
DF5FH

[DH1KLM]

Gibts doch schon alles.
https://github.com/pavel-demin/stemlab- ... s/releases

[df5fh]

Oooops ... danke

[DC9OE]

.... unter viewtopic.php?f=76&t=405 findest Du ein paar Messdaten.

Und wir haben den STEMlab 16 auch schon in einem konkreten Gerät im Einsatz.

73, Edwin - DC9OE

PS. das einzige was noch nicht geht ist der VNA... für Heft 5 der CQDL habe ich einen Artikel dazu geschrieben.

Baugruppen und Zubehör gibts unter: www.smartradioconcepts.com

[DC9OE]

Hi Pavel, many thanks I will try and let you know.
Markus and I tested on Tuesday, but may be we have not used the latest version.

Kind regards, Edwin

[df5fh]

Das ist ja ein Ding ... da glaube ich, alle sind noch in der preorder-Liste von RedPitaya.com, dabei hat Pavel schon alles fertig. Bin gespannt, wie lange ich noch warten muss

73, Henning

[DK7XL]

Pavel, Edwin,

the most recent update on FW for 122.88-16 tells that TX output level has been increased for compatibility reasons to HPSDR transceiver. What is the new level now?

Thanks and 73s,

Klaus

[DC9OE]

... just a little addition for clarity.
Pavels SW allows Stemlab 16 to provide the maximum output feasible.
This is about 2,7dBm on 10MHz down to 0,8dBm on 50MHz.
(reason ist that there is no amplifier in Stemlab 16)

This is less than what Stemlab 14 provides (about 9,5dBm on 10MHz and about 6,5dBm on 50 MHz)

The Problem for people using HPSDR is in some limitations of the TX setup.
In this setup a dB Level can be provided to match changes in driver levels.
The problem is that this setup is limited to a minimum of 38,8dB - which is probably not enough in case you want to replace Stemlab 14 by Stemlab 16.

Therefore this either requires a modification or alternatively you can use our Charly 25 edition of Power SDR.
This version is backward compatible to everything else but does not have the limitations above. TX levels can be set to 0dB in this SW.

We have put a link to our version of the SW here: www.smartradioconcepts.com

73,Edwin - DC9OE

[DC9OE]

Ernst, sorry for this , I will check with Markus and make sure the links are correct,

73,Edwin

[DC9OE]

Ernst I have just checked myself, if you use the link in the shop you end on this page:

If you go under BETAS & RELEASES, the latest version in there is this one:

This is from February and it is a Beta of course as we are still busy optimizing code for Charly 25 Boards and STEMlab 16.

Hope this helps.

73,Edwin

[DC9OE]

Hi Ernst,
thanks and yes I agree we have a lot of documentation to do, both on HW and SW and the plan is of course to do it.
Problem is time - we are always in conflict between development (and now also production) and documentation...

One day we will get there hopefully by the time of Ham Radio ....

73,Edwin

[DC9OE]

.. kurzer Hinweis - mit der neuesten Firmware Version von Pavel funktioniert der VNA wieder.

Details finden sich unter CHARLY 25.

73,Edwin

[Yevgeni]

Hello.
Meine ersten Proben RP 16 BIt.
https://www.dropbox.com/sh/a1yecde4hs91 ... g.pdf?dl=1
73 de RZ3QS

[Yevgeni]

Hello.
Meine ersten Proben RP 16 BIt.
https://www.dropbox.com/sh/a1yecde4hs91 ... g.pdf?dl=1
73 de RZ3QS

[Yevgeni]

Hello.
Meine ersten Proben RP 16 BIt.
https://www.dropbox.com/sh/a1yecde4hs91 ... g.pdf?dl=1
73 de RZ3QS

[DD8JM]

Hello, Yevgeni,

thanks for your contribution, I have put it on CQ-NRW.de, not all read it here in the forum.

Greetings Jörg, DD8JM

[DC9OE]

Hi Yevgeni,

brilliant measurements - many thanks, you filled some gaps for me which we could not measure because our own equipment was to noisy.
The trick of changing the input voltage settings is a good one, I will test it on our stemlabs.

Interesting to see that you came up with 2dB more sensitivity for MDS (our measurements came up with -122dBm).

Anyway, many thanks again, you provided a very good overview and in fact it underlines that STEMlab 16 can either match or outperform any other Direct Sampling TRX currently on the market.

73,Edwin - DC9OE

PS. und Jörg danke dass Du die Messergebnisse hier reingestellt hast, sie haben für uns eine Lücke geschlossen und ersparen uns weitere Arbeit

[Yevgeni]

Hello DC9OE.
Links to video measurements, sorry in Russian.
https://www.youtube.com/watch?v=rYndCf-V5iA
https://www.youtube.com/watch?v=8zq-O2PHNLk
https://www.youtube.com/watch?v=lEhlx9TDEVE

[DC9OE]

Hi Yevgeni, thanks for the Video's - interesting but somewhat difficult for me to follow.

One question on sensitivity measurement because I'm not sure I understood your method correctly.
From what I understood from the video it looks to me as if you have taken the noise floor in a bandwidth of 500 Hz and the outcome was -124dBm.

In this book: http://www.arrl.org/shop/Amateur-Radio- ... ce-Testing

the ARRL describes the test procedures they are using in their labs and according to them, MDS is defined by a signal which is 3dB above the noise floor.
In your case MDS would be roughly -121dBm using this definition.

When using this method, I ended up with -122dBm and as I was wondering where the differnce to your measurements came from - this might be the answer.

You might find the book interesting it gives good definitions on the procedures used by ARRL (I think the text is also available on the internet somewhere).
The same procedures are used by Sherwood Engineering for their Sherwood List.

Thanks again for the good work and best 73, Edwin -DC9OE