Feedback for version 1.0a here

[SteveAndrew]

Hi Steve,

I mean such a function by which the white trace becomes flat (0dB - reference line) so the yellow trace will be displayed in relative to the white one. This is because noise generators will not give out uniform output from 1kHz to 2GHz, and also we don't need absolute dBm readings when it comes to measuring filters.

73,

Yas - JA8SCD Tokyo

Hi Yas

Understood, thank you.

I did have some thoughts in that direction when the original analyser but were dropped for various reasons. What I had considered was adding a trace-maths function so that the difference between two traces could be plotted with it's own scaling. I think that would do what you are asking without the need for a normalisation or calibration run. I think it would be a useful feature, and something worth considering - No promises that it will make it into V1.0 though.

Steve

[briansmithers1701]

I'm just getting to grips with this software and thanks for making it available.
A little feedback....

I have my SDR Play built into an old radio chassis with a nice switched attenuator built in. There's also room left for the tracking generator (next thing to build) and a wide band noise generator module - currently on the way from China.

My workshop computer is one of those not very powerful small format units that screw on the back of the screen. It is running Windows 10.

I see in the release notes that under item "2" you are aware of the screen intermittently freezing. Mine does that but only when the sweep is wide - like 10MHz or more. At the lower sweep settings it runs OK. I imagine that many people will be running a PC better than mine so hopefully this data is of some use to Andrew. If it is happening on many other (faster) computers then it probably isn't processor speed related (or is it!).

Another observation made yesterday was that when looking at an injected signal - which as I steadily increase, the displayed amplitude stops increasing at some point as I reduce the manual attenuator that I fitted. Some kind of "AGC" I suspect - but when it starts to do that I assume that the message is to not increase it any more or some smoke might escape from the SDR Play unit.

There is a very neat and inexpensive switched attenuator recently appeared on a blog that I follow which may interest forum members...
http://kv4qb.blogspot.com/2019/04/63-db ... uator.html

Regards
Brian

[SteveAndrew]

Hi Brian

I see in the release notes that under item "2" you are aware of the screen intermittently freezing. Mine does that but only when the sweep is wide - like 10MHz or more. At the lower sweep settings it runs OK. I imagine that many people will be running a PC better than mine so hopefully this data is of some use to Andrew. If it is happening on many other (faster) computers then it probably isn't processor speed related (or is it!).

The freezing problem is a bug and will happen on any computer irrespective of speed. The problem has now been fixed.

Another observation made yesterday was that when looking at an injected signal - which as I steadily increase, the displayed amplitude stops increasing at some point as I reduce the manual attenuator that I fitted. Some kind of "AGC" I suspect - but when it starts to do that I assume that the message is to not increase it any more or some smoke might escape from the SDR Play unit.

There is no AGC. The reference level sets the level at the top of the display, as well as controlling the LNA and IF gain settings. If the signal is getting close to the reference level, then it might be time to select a higher reference level. The reference level has no control over the unit's smoke-emission control system. The maximum input to an RSP unit is +10dBm, for short periods, otherwise, 0dBm is considered to be safe for continuous levels.

Steve

[PeterW]

On some old "or newer" HP Spectrum analyzers I remembered that if I put in "zero" span or something you could listen to the signal in a built in AM/FM detector, could that be some feature to add in future ?

//Peter

[SteveAndrew]

On some old "or newer" HP Spectrum analyzers I remembered that if I put in "zero" span or something you could listen to the signal in a built in AM/FM detector, could that be some feature to add in future ?

//Peter

Hi Peter

It's on the list of things to think about, and will eventually happen. I can't give you a timeline at this point.

Steve

[yesitsdrew5310]

Thank you so much for your time on this program Steve! I would really love the ability to export a .csv file with the MHz and dBm readings from the scan. This would make this a very useful tool in the Professional Audio arena as an RF Spectrum Analyzer to import this file directly into the tool we use to calculate IMD and available frequencies for programming our wireless microphones.

The dream for me would be to have a .csv file that had the frequency in MHz in one column and the dBm measurement in the next.

In a text editor the .csv would read:
240.000, -95.0
240.252, -105.0
240.504, -98.0
240.757, -103.0

and then continue to the last frequency sampled.

Is an addition to the program like this possible? Thanks!
--Drew

[SteveAndrew]

I would really love the ability to export a .csv file with the MHz and dBm readings from the scan. This would make this a very useful tool in the Professional Audio arena as an RF Spectrum Analyzer to import this file directly into the tool we use to calculate IMD and available frequencies for programming our wireless microphones.

The dream for me would be to have a .csv file that had the frequency in MHz in one column and the dBm measurement in the next.

In a text editor the .csv would read:
240.000, -95.0
240.252, -105.0
240.504, -98.0
240.757, -103.0

and then continue to the last frequency sampled.

Is an addition to the program like this possible? Thanks!
--Drew

Hi Drew

Data export is on the future developments list and will include data in CSV format. I can't give you any sort of timeline at the moment, but it will probably make the cut along with other additions in the next update.

Steve

[yesitsdrew5310]

That is great! Thanks so much!
--Drew

[Brian VK6LO]

I have indications that Tuner selection on the DUO is 'flaky'

1. Operating with signal input to Tuner 2 displayed then stop the program with Tuner 2 still selected and close the program

2. Restart the analyser and Tuner 1 is now highlighted but the signal from Tuner 2 connection is displayed - select Tuner 2 = no signal displayed

3. Reselect Tuner 1 and signal from tuner 2 displays then select HighZ and signal disappears (correct)
With input still on tuner 2 select 2 and signal may or may not be displayed

It seems that initial program start highlites tuner 1 in the program but does not select tuner 1 in the radio and from then on various combinations of tuner selection may or may not happen correctly

Brian

[glovisol]

Hi Steve,

There is a "false start" problem whereby on switch on of a measurement previoulsly set up and OK the Spectrum Analyser comes up wrong, like if it was overloaded. Then, by altering the REF level and going back the SA recovers, as shown in the enclodes pics. Otherwise I have been working for several days with this 1.0a software and it is really a dream!

Kind regards,

Gianfranco