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Re: Using SDR# to drive the SDRplay RSP

Posted: Wed Jan 07, 2015 12:41 pm
by sdrplay
See our first independent review of SDRplay being used for Broadcast VHF DXing on

Re: Using SDR# to drive the SDRplay RSP

Posted: Wed Jan 07, 2015 12:44 pm
by sdrplay
New version of the SDR# plugin is now available on the page (V1.3 build 1014) please report any bugs / issues here.

Re: Using SDR# to drive the SDRplay RSP

Posted: Wed Jan 07, 2015 12:49 pm
by sdrplay
Just to reiterate a point which comes up a lot - : neither the CR1 nor the Funcube dongle pro plus use the full Mirics chipset. They both only use the tuner. So the RSP is the first SDR platform to use the full Mirics chipset of the MSi001 and MSi2500.

Re: Using SDR# to drive the SDRplay RSP

Posted: Wed Jan 07, 2015 12:50 pm
by sdrplay
The SDR# plugin includes an AGC loop. The advantage of using the Mirics chipest to do USB conversion is access to a range of receive bandwidths. The default setting is 1.536MHz When the AGC is active, it alters the gain settings to avoid overloading the A/D converter and the changing gain settings can be viewed in the control panel. However, when you disable the AGC, rather than reverting to a default value, the gain settings remain at the last value set by the AGC system. This is a deliberate plan that’s designed to give the user, a good starting point for any manual adjustment. This can cause a bit of confusion but is designed to stop you getting into trouble with what so many options to choose from. By using the AGC to get you close to a suitable setting for a particular signal, your are then well placed to go on and manually improve further. There''s always the ''Load Defaults'' option if you get confused at any time. For more technical detail on our AGC - go to\n

Re: Using SDR# to drive the SDRplay RSP

Posted: Wed Jan 07, 2015 1:05 pm
by sdrplay
Check ou the latest video which talks through the SDR# setup process on\n

Re: Using SDR# to drive the SDRplay RSP

Posted: Wed Jan 07, 2015 1:19 pm
by sdrplay
First of all I would like to state that we are full of gratitude for those people who write the code (SDR#, SDR# plugin, drivers etc. etc.). That said, I would like to write down my personal "user requirement" about a problem I have using SDRplay plus SDR#.\nIf one want to make a "quantitative" or "semi-quantitative" use of SDR#+SDRplay (e.g. do some comparison with different set-up, different signals, different antenna etc.), you have a simple and efficient tool: you can take a snapshot and you can compare different snapshot etc. etc. Now, if you do not use zoom you have all the bandwidth displayed and, for some IF BW / SR, it is all displayed in a little portion of the available window. In such a way you can not see details of the signal under study. So you use zoom. But you have a little control over zoom. In a word you should know how many zoom you have (I mean, a number, let say zoom=1.5). Knowing the zoom figure you can -- from time to time -- make comparison of signals etc. (provided that you set the same value of course).\nThis -- maybe -- could be implemented in SDR# plugin. The SDRplay plugin should have a new input/output control (field) with this specifications:\n-- the target is to "fill" the FFT windows exactly with the IF BW\n-- if you set a IF BW value (in the plugin window), the plugin will automatically set and show the value of the "zoom"\n-- then user can change that value of zoom (and now he or she can write down that new value in order to make repeatible measure/picture) \n-- the value of zoom should be saved in a config file and recalled in the next launch\n-- nice to have: in the config file user can set their own values of zoom for each BW/SR allowed let say e.g.\n--> key=xyz BW=1.5M SR=3.0M ==> zoom=1.5 \n--> key=xyz BW=0.2M SR=3.0M ==> zoom=3.8 and so on...\n\nWho can help? TNX\n \n

Re: Using SDR# to drive the SDRplay RSP

Posted: Wed Jan 07, 2015 1:20 pm
by sdrplay
I hear what your saying about the display not scaling around the filter for the lower bandwidths. The problem here is that SDRSharp uses the sample rate to dictate the size of the display window rather than the filter bandwidth. I can look into your suggestion or see what else we can do on the next iteration.\n

Re: Using SDR# to drive the SDRplay RSP

Posted: Wed Jan 07, 2015 1:20 pm
by sdrplay
TNX Ian. To reduce the development effort I try to give basic requirements in order of priority:\n1-- to have a way to set the scale numerically (maybe a new input field in the SDRplay-SDR# plugin...)\n2-- nice to have: save that value from run to run\nI think you get the issue and any solution you can find is welcome.\n(by the way: I presume the sdr# plugin for sdrplay is developed by "sdrplay limited" as a free of charge unsupported tool).\n

Re: Using SDR# to drive the SDRplay RSP

Posted: Wed Jan 07, 2015 1:21 pm
by sdrplay
OK.. Will do in that order. I am looking at code development for HDSDR at the moment but I will come back to SDR Sharp after that with your suggestions. The software for the SDR Sharp plugin is supplied exactly as you described. I am sure it should be possible to make the source code for the plugin available on a public license to take and do with as you please if you want to make progress in the meantime.

Re: Using SDR# to drive the SDRplay RSP

Posted: Thu Feb 19, 2015 1:41 pm
by CaptainNemo
Hi Jon and hi all the sdrplay ltd team.
And hi all the readers of this forum.

Referring to the pdf guide "Using SDR# with the SDRplay module"
(SDRplay Ltd "plugin" Version 1.3 Build 1014)
here are some questions, just to see if I well understood.
Please feel free to "expand" the discussion to any useful concept.

IF Mode
– Sets the tuner into either Zero IF mode or Low IF mode.
There are three different IF modes available 450kHz, 1.62MHz and 2.048MHz.
The IF bandwidth drop down menu will automatically update with the appropriate
selection of IF filter bandwidths.

When should I use IF mode greater than zero? Can you tell something about?

IF Bandwidth
– Sets the bandwidth of the IF filter.
The selections available will depend on the IF mode selected.
For the full range of IF bandwidths selections then the tuner must be operating in ZIF mode.

Enable Tuner AGC
– This enables a software AGC leveling routine within the plug-in
that attempts to change the gain reduction value to achieve a specified signal
power at the ADC input.
The level which the routine will adjust the ADC input power towards is defined
in the Setpoint control box.
In this mode it is not possible to adjust the tuner gain reduction manually.

>>> Q:
What are the relationships of this option with the ACG option in SDR#?
Which is the best setting for this two "ACG" checkboxes?

Gain Reduction
– When the AGC is enabled this dialog box shows the current value of
the gain reduction selected by the AGC routine.
When the AGC is disabled this can be used to manually control the gain of the tuner.
The gain reduction value controls the amount of gain, in dB,
that the maximum tuner gain will be reduced by.

LNA GR Threshold
– The point at which the LNA turns off within the gain reduction range
can be controlled by value in the LNA GR Threshold.
By lowering the value the LNA will turn off closer to maximum gain.
Increasing the value means that the LNA will stay on for longer thus providing
better noise performance but at the added risk of overload.

>>> Q:
I understand from SDRplay ACG documentation:
let's assume HF (3-30MHz)
LNA GR 0 or 19dB - MIX GR 0 or 24dB - IF GR 0 to 59dB
overall GR range 0 - 102dB
if I set "LNA GR Threshold" to 0 LNA will be always OFF
if I set "LNA GR Threshold" to 102 LNA will be always ON

Sample Rate
– Sets the sampling frequency of the ADC.

>>> Q:
Suppose I set IF bw 1.5MHz and SR 1.5MHz.
According to "Shannon" SR should be 2xBW. I suppose this means the SR is
1.5 on I channel and 1.5 on Q channel so Shannon is "OK". Right?
Then suppose I set IF bw 1.5MHz and SR 3.0MHz. What difference should I notice
on my FFT? And what if I double again, SR = 6.0MHz and again to SR 12.0?

– Sets the target level power at which AGC routine will attempt adjust
the power on the ADC input.
A larger value will position the signal near the top of the ADC range.
A lower value will reduce the signal power and hence levels at the ADC input.

>>> Q:
The level I see on the SDR# FFT is a "power"? In other words the FFT is a plot
of power as function of frequency?
So, let say "Setpoint" is -15, means when somewhere in the FFT display
a signal reach -15dbfs this trigger sdrplay's ACG?

TNX in advance.

btw -- any news about sdr# plugin v1.4?
dont forget "ppm correction" and "scaling" bw to the available FFT horizontal space...