PowerSDR-Flex5000 Transverter Pictures

1. When I use XVRX as the receive input port to the Flex5000 from my transverters I get major digital noise that is the same across all 11 transverter bands from 50 MHZ thru 24 GHz, that I don't see if I use RX1-IN or ANT1.

If I uncheck 'Split RF' in the PowerSDR xvtr setup page and connect the receive cable to XVTX/COM, I get the same effect as if I was using 'split RF' and had the cable connected to XVRX:  noise that is not present when ANT1 or RX1-IN is used.

If I disconnect the coaxial cable bringing the transverter receive signal to the Flex5000 the noise disappears.  Much of the noise is coming from my SDR-IQ, which is also connected to the transverter line with a splitter.  I suspect that the other noise is coming from other digital equipment in the environment. 

To illustrate the problem, I have attached 4 appropriate screen grabs from PowerSDR:

First, the PowerSDR screen with the 144 MHz transverter/Flex5000 receiving a 2 meter CW beacon at 144.285 using XVRX to receive the signal:






Second, below, the Power SDR screen when feeding the same transverter signal in via the
ANT1 port.  Note the absence of the noise:





Third, below, the PowerSDR screen when feeding the same transverter signal in via the
RX1-IN port.  Note the absence of the noise:

Fourth, below, the PowerSDR screen when feeding the same transverter signal in via the XVRX port, but with the SDR-IQ disconnected from its splitter.  There is still more noise than when ANT1 or RX1-IN is used, but much less noise than when XVRX is used with the SDR-IQ connected to the splitter. 

Below are additional images taken with 'Spur Removal' on and off, and with the FT1000MP on and off:

First, Spur Removal On and FT1000MP On:

Next is the image with Spur Removal Off and FT1000 On:

Next is the image with Spur Removal Off and FT1000 Off:

And here is the image with Spur Removal On and FT1000 Off:

Eric Wachsmann sent me a modified firmware that turns the preamp on for the transverters [default is that it is off for the transverter modes and on for 28 MHz].  When I install and run this there is no problem with any noise even with the SDR-IQ back in line and with the FT1000MP turned on.  Here is the picture of "success":

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