Helllo all.

In the spring I intending putting up 4 x 6 ele XPOL antennas for 6m EME. Of course I will be using the same system during the Es season and so need 2 things.

1. Good dynamic range for the Es season
2. 2 channels which must be coherent for adaptive EME

In fact on Es I will run WSJT-X decoders for FT8 with 0, 45, 90 and 135 degrees. I know from the work of others that there can be a lot of rotation on multihop Es. I think that this will be very interesting which is why I am making the effort.

I have a 2 channel Afedri AFE822x which is almost good enough but I need better dynamic range. What is available?

Regards

Conrad PA5Y

I’m afraid you have no options, if you need such a radio you’ll have to design it yourself.

Hello Peter, no I don’t think so. The RSPDuo would probably just about work for EME but would collapse during a typical EU summer Es opening.  They have quite poor RM performance and require a sample rate conversion because as far as I am aware a 96kHz sample rate is not possible. A 96KHz BW is needed for MAP65.  

I think that Simon’s appraisal was correct. I will have to roll my own probably based on the IQ+ RX. I have a UADC4 already that I use on 2m EME.  For 6m EME the Afedri AFE822x in alias mode is good enough and I already have one. I just wondered if anything else had come along meanwhile that can handle big signals.

I wish that there was such a thing as a 2 channel Perseus, I still really like my Perseus.

Regards

Conrad

Hello Erik.

SDR Uno cannot provide a coherent IQ stream over USB so it will not work. I think that it is most likely that this is not of general interest to the group so I will stop. The BW for MAP65 must be 96kHz and any form of resampling or sample rate conversion invariably creates additional problems. Simon was right I must make my own hardware. My best bet is to make a 2-channel converter and use an UADC4 4 channel ADC. This will be coherent, and it will give me RM dynamic range of 120dB! The challenge is making a good enough coherent down converter with a good enough LO.

You can read a little about this device here:

http://www.sm5bsz.com/linuxdsp/hware/ensemble.htm

There are so few people using these methods that I would not ask Simon to support it.

73

Conrad PA5Y