SmartSDR and MRP40 input method?

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Hi all,

Needing some help with MRP40 setup.  I setup the normal version and it works except for the input level.  I crank up the slice RX stream all the way but still only get about 10% input to it.  I also tried the SDR version which "sounds" like it would be the way to go but for the life of me can't figure how to get any input to it.  Any ideas?  Thanks.
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Vincent Martin - N5ATM

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Posted 2 years ago

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Mike - VE3CKO, Elmer

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Didn't have a clue what MRP40 was til I googled it. I can offer some advice as the SDR version states it "demodulates IQ-signals with a bandwidth (sample rate) of 48Khz, 96Khz, 192Khz"
I downloaded it and installed the 30-day trial. I first tried using DAXIQ which  seem clumsy but it did work then tried just a DAX channel, here is what I did and results. When you open up MRP40 you see three areas, for reference we'll call them top, middle and bottom. Here is what you need to do.

DAXIQ Method: To get IQ signals you first have to setup SmartSDR select the DAX on the left menu then select a DAXIQ channel 1 and then look at the DAC Control Panel, down at the bottom IQ Stream 1 should be on the frequency your slice is and the "1" should be blue, set the sample rate such as 96000.
In MRP40 go to Options, Show, Soundcard. Udser Select Rx Soundcard, select DAX IQ RX 1 then close window. The use of this seemed a bit difficult but it worked. In the top area you have to move the vertical yellow bar to the CW signal, when doing this the frequency offset is displayed in red on the right side of the middle window. Then in the middle window move the red horizontal bar on top of the blue CW dits and days you see, then the text will be decoded in the bottom area. 

DAX Method: In the slice select a DAX channel such as Channel 1 and then look at the DAX Control Panel, RX Stream 1 should be blue and you should be seeing activity in the meter.
In MRP40 go to Options, Show, Soundcard. Under Select Rx Soundcard, select DAX Audio RX 1, close the window.
The dits and dahs started showing immediately with a delay and just move the red horizontal bar to over top of the blue dits and dahs and the text starts decoding again visible in the bottom area.

Obviously I'm not an expert on this MRP40 software but in summary I think I can generalize the IQ method will get you the spectrum of cw where the slice DAX method will get you the cw signal your slice is tuned to.
Hope this is helpful Vincent.