Thursday, October 26, 2017

Fast propagation research with FT8

I think it is now evident FT8 is the most interesting digimode today for research of realtime propagation. And it is fast! Really fast! However for good research you need to receive and to transmit as propagation is not always reciproke. My idea was:

Start at band 10m and first receive 2x 15sec. timeslots to see were you can transmit in the waterfall. Then 3x transmit 15sec and 3x receive 15sec, In total 120sec=2 minutes in total for each band.
You can scan 10m-160m in 10x2=20 minutes and you got an idea how bands are at that moment.

Well, I can tell those 20 minutes became longer after all when I started this experiment as I used CQ for transmission and got stations back to me on some bands. Besides that I noticed 5T2AI from Mauritania on 20m FT8 with a strong signal which would be a new one for me. So I returned to 20m before I made the screenshots and worked 5T2AI for a second ATNO this year.

A overview from about 18:00 UTC yesterday evening:

Complete picture all bands

10m, I immidiatly had response. But no DX propagation.

12m, nothing at all. PSK reporter comes back with all stations monitoring 12m at that time.

15m, I didn't hear anything but they heard me! Typical non reciproke propagation.

17m

20m looks good but I was here about 30 minutes.

30m

40m

60m

80m

160m

All transmissions done with 25W. Except 60m were 15W is the legal limit. Antenna still is the coppertape multiband vertical at 9m agl.

4 comments:

  1. Hallo Bas, ik werp een blik op SDR Twente en ik weet meteen hoe de condities zijn op HF. 73 Paul PC4T

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    Replies
    1. Hallo Paul, de webSDR zit ver bij mij vandaan. Condities zijn daar vaak heel anders. Ik wil de condities weten op mijn QTH op mijn tijd. Dan is dit ideaal! Buiten dat kom je tijdens de scan vaak leuke DX tegen. In dit geval voor mij Mauretanië. Ik vind FT8 wat dit betreft echt ideaal. 73, Bas

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  2. Hallo Bas en Paul, ja inderdaad op WebSDR kun je snel zien hoe de goed de condities zijn. Maar met FT8 via je eigen installatie en antenne zegt meer hoe de condities voor jezelf zijn. 73 Hans, PE1BVQ

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    Replies
    1. Precies, en zoals ik hierboven al schreef in de reply. Je kan leuke DX zien. Als die DX dan ook nog signalen heeft van -6 tot 0 dB dan weet je haast zeker dat je het kan werken. Ik hoop dat men op Bouvet Isl. volgend jaar echt op alle banden FT8 gaan gebruiken. 73, Bas

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Thanks for your comment. Bedankt voor je reactie. 73, Bas