29MHz trans Atlantic DX...

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M0DTS
Posts: 684
Joined: Sun Feb 24, 2008 9:03 pm

Re: 29MHz trans Atlantic DX...

Post by M0DTS » Sun Nov 06, 2022 3:00 pm

I've got my TX rigged up now.
I can see myself on a kiwisdr nr Washington: http://kiwisdr.k3fef.com:8073/

If someone had a good antenna and rx maybe it would work, but would have to catch it when the fading is not as brutal!!
DRM mode may be the only way.
This is 66Ks DVB-S2, 29.250MHz.

Rob
Attachments
sdr rx_fading.jpg
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sdr rx.jpg
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Last edited by M0DTS on Sun Nov 06, 2022 3:29 pm, edited 1 time in total.

M0SKM
Posts: 375
Joined: Sun Jul 13, 2014 3:15 pm

Re: 29MHz trans Atlantic DX...

Post by M0SKM » Sun Nov 06, 2022 3:20 pm

Found your callsign and just heard what sounded like distorted sideband on your frequency. Possibly another operator.

Steve
Find me on the LEO/MEO satellites.
https://m0skm.com/2024/03/29/worked-all-states/

M0DTS
Posts: 684
Joined: Sun Feb 24, 2008 9:03 pm

Re: 29MHz trans Atlantic DX...

Post by M0DTS » Sun Nov 06, 2022 3:25 pm

Yeah, there's a few signals come up since i posted!

Signal is very QSB, that's 100W into 3el yagi here.
The Rx says it's a loop: https://sites.google.com/view/vk1hw/ant ... ermes-loop

Rob

radiogareth
Posts: 1371
Joined: Wed Jan 06, 2016 9:46 am

Re: 29MHz trans Atlantic DX...

Post by radiogareth » Sun Nov 06, 2022 3:29 pm

Looking good Rob.....
I have so much HF QRM at home that my spectrum looks like that already, with or without any DVB, but am watching on my SDR.
Been playing with this little amp https://sites.google.com/site/rfpowerto ... ower-tools which I built a couple of years ago.
From Mikes transverter O/P into a 20db eBay amp gave 0.1W. Then into this amp gave me 6 watts. More was seen but tweaking the bias greatly improved the 'byproducts' until I think I have popped the device (really need a current limited 50V PSU.....). No smoke but its stopped amplifying......
I have several spare PCBs for this amp if anyone would like one....it would probably be good for a beacon amp running relatively QRP if the band obliges 5W will probably work.....or I suppose tunr down a MRF300 would achieve the same.....tx output filter also required....
Gareth

g0mjw
Posts: 2568
Joined: Sat Sep 20, 2014 9:15 am

Re: 29MHz trans Atlantic DX...

Post by g0mjw » Sun Nov 06, 2022 3:40 pm

I am just looking but I don't see any signals. The SDR queue is full.

g0mjw
Posts: 2568
Joined: Sat Sep 20, 2014 9:15 am

Re: 29MHz trans Atlantic DX...

Post by g0mjw » Sun Nov 06, 2022 3:47 pm

I can see that carrier, I tried sending a CW carrier but it doesn't appear, so no path for me at the moment.

M0DTS
Posts: 684
Joined: Sun Feb 24, 2008 9:03 pm

Re: 29MHz trans Atlantic DX...

Post by M0DTS » Sun Nov 06, 2022 3:48 pm

Sounds good Gareth,

You maybe able to hear some backscatter from me on ssb maybe but DVB unlikely as it will be too weak.

The DATV source:
Pluto -> ham-it-up converter -> SPF5189 -> RD06 -> BLF188 and LPF.

Image below, excuse the tip of bench, work in progress!!!!!!

Rob
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20221106_154527.jpg
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M0DTS
Posts: 684
Joined: Sun Feb 24, 2008 9:03 pm

Re: 29MHz trans Atlantic DX...

Post by M0DTS » Sun Nov 06, 2022 3:57 pm

Stronger than it was now, but major frequency selective fading.

good signal on my local kiwisdr only about 2 miles away.
http://planet3.dyndns.org:8073/
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sdr rx_stronger_2.jpg
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M0DTS
Posts: 684
Joined: Sun Feb 24, 2008 9:03 pm

Re: 29MHz trans Atlantic DX...

Post by M0DTS » Sun Nov 06, 2022 4:23 pm

Possibilities with this sort of strength, more stable too.... interesting.

Rob
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spectrum.jpg
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sdr rx_stronger_3.jpg
sdr rx_stronger_3.jpg (568.41 KiB) Viewed 4228 times

M0DTS
Posts: 684
Joined: Sun Feb 24, 2008 9:03 pm

Re: 29MHz trans Atlantic DX...

Post by M0DTS » Sun Nov 06, 2022 5:37 pm

Some more images of Today's tests, Tx is now off as conditions have faded in darkness.
The strongest peak came up to 20dB/noise on the websdr.
I did a comparison with 66Ks DVB-S2 vs 333Ks DVB-T.

Rob
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strongest peak.jpg
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66Ks vs 333Ks.jpg
66Ks vs 333Ks.jpg (160.46 KiB) Viewed 4214 times

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