Early stability results for RSPDuo stability and suggestion for future versions of Uno

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MTG
Posts: 38
Joined: Sun Feb 12, 2017 6:07 pm

Early stability results for RSPDuo stability and suggestion for future versions of Uno

Post by MTG » Wed Oct 24, 2018 9:33 am

I have a couple a few weeks of setting up and using Uno and Duo (does that make Tr ;-) ) and have some early comments on its performance and a few suggestions for future versions of Uno.

The frequency stability seens to be better than my RSP2-Pro; using a GPS reference calibration the two tuners have settled down to a standard deviation of withing 1.5 Hz in 143 MHz for day periods compared to 3 Hz for the RSP2. The calibration frequencies are output on VACs and recorded every 1 minute. Both tuners match each other, following the small temperature drifts in my receiver room. There are a few spurious points which I have yet to evaluate. Using the reference frequency capability will of course improve things ... but not bad without ;-)
CalFreq1.jpg
CalFreq1.jpg (54.21 KiB) Viewed 6525 times
In another post I have spoken of my problems with output level shifts and that has yet to be resolved. However, the calibration signal levels between the two tuners are again well matched and stable. The SNR is around 35 dB and the monitored levels over an 8 hour period is shown below. The standard deviations in these dBm levels for the two tuners is 0.34 and 0.07 dB. Variations seem reasonable for the SNR.
Callevel5.jpg
Callevel5.jpg (61.24 KiB) Viewed 6525 times
My suggestions arise from having to balance settings and repeatedly stop, close and restart during this initial testing period. They may be particular to my usage but they are minor and I imagine would be easy to impliment and would enhance the program. With multiple tuners and proposed diversity, noise cancelling and antenna combining possibilities the ability to match tuners is important.

1. The ability to set the start and end of the bandwidth by entering numbers rather than dragging the red lines in SP2. ie. having variable, settable bandwidth high and low limits. Also to retain these settings when the instance is closed (it is most frustrating for me to reset each time I re-open Uno.
2. A display of the level of the volume control setting as a number (or settable) rather than just sliders.
3. When version 1.4 arrives it is hoped that as well as the ability to display and adjust the phase between the tuners, there is a facility to generate an output file with the phase differences and/or individually (arbitrarially referenced) phases.

Thats probably enough for now :D

Reason: No reason

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