[Linrad] Re: First real EME tests with MAP65-IQ

Hi Gabriel and ALL

To avoid confusions will be nice if we specified MAP65 or MAP65-IQ in our references, and not simple MAP65 for both softwareâs.

ÂMAP65 works with adaptive polarization and MAP65-IQ not, to avoid confusion regarding the software version is good to start from the beginning making clear differences between both version, in essential both works decoding JT65 BUT MAP65-IQ is the little brother for single channel IQ receptors when MAP65 is for dual RX IQ channels with Adaptive polarization.

73 de Alex, HB9DRI

From: linrad@xxxxxxxxxxxxxxxx [mailto:linrad@xxxxxxxxxxxxxxxx] On Behalf Of Gabriel - EA6VQ
Sent: Samstag, 28. MÃrz 2009 14:09
To: linrad@xxxxxxxxxxxxxxxxxxxx Subject: [Linrad] First real EME tests with MAP65-IQ

Yesterday I spent several hours playing with the new version r1102, and using the default configuration of Linrad provided with that version. This is the first time I have managed to decode signals using MAP65 and I must say the first impression is excellent, however I have noticed several things possibly not working as good as I could expect, at least with my setup:

First, the signal levels reported for the selected frequency are between 3 and 5 dB weaker than with WSJT6. I was running MAP65 and WSJT6 in parallel and I could see that difference for all signals. When a signal is, for instance, -22 dB in WSJT6, the same signal is between -25 and -27 dB in MAP65. When the band is noisy the difference is smaller (might be 1 dB weaker in MAP65), possibly because of the excellent noise blanker of Linrad.

Also, weaker signals (-28 to -30 dB in WSJT6) are not decoded at all in MAP65 (and they are in WSJT6)

Additionally, the reception of MAP65-IQ suddenly stops. The waterfall display does not update and the program doesn't decode, although apparently it continues receiving data from Linrad (at least it does not show "no data" or so). When I double click on the waterfall it starts receiving again. This has happened at least 5 times in about 2 hours.

Finally, near the moonset the band was really noisy and I noticed that some signals that were clearly visible in Linrad's waterfall were not visible at all in MAP65's waterfall, and it did not decode them either. Anyway this was only in very noisy conditions, due to power lines. (Joe, I have some screenshots of these last 2 situations, and I will E-Mail them to you)

73. Gabriel - EA6VQ
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