24GHz dx..
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This forum is run by the BATC (British Amateur Television Club), it is service made freely available to all interested parties, please do not abuse this privilege.
Thank you
24GHz dx..
Since the fail for a valid qso during the contest (Sync but no lock! @56km) i've been receiving Terry, G1LPS's 24GHz FM ATV test signal at various strengths from home through trees at Terry's end!
The distance is 28km but i'm sure we can better that
For information TX is very simple, 10mW gunn module using modified Bob Platts GUNNMOD driver (5v diode bias on 24G GUNN units) into a 25dB horn antenna about 25cm long.
You can get similar modules from K-Band PIR units.
Rx is a modified 26GHz Alcatel unit from ebay using an Elcom synthesiser as the LO (22.8GHz for 1.2GHz IF). It's performance with little modification is very good but i have built a DB6NT 24GHz LNA from kit to improve things.
Using a 60cm dish with ~2.5deg beam width and a dual band 10/24G feed so i can line up on 10GHz signal first.
Some info here on the Rx:http://www.m0dts.co.uk/index.php?tag=24GHz&item=97
Today result after a bit of tweaking is near enough P5 signal over 28km path.
If anyone has any idea whether there's any UK records/previous activity for 24GHz ATV I'd like to know
52km test is next test then maybe 115km in the near future.
I hope to monitor signal vs weather soon to see how it's effected compared to 3cm.
Rob
M0DTS
The distance is 28km but i'm sure we can better that
For information TX is very simple, 10mW gunn module using modified Bob Platts GUNNMOD driver (5v diode bias on 24G GUNN units) into a 25dB horn antenna about 25cm long.
You can get similar modules from K-Band PIR units.
Rx is a modified 26GHz Alcatel unit from ebay using an Elcom synthesiser as the LO (22.8GHz for 1.2GHz IF). It's performance with little modification is very good but i have built a DB6NT 24GHz LNA from kit to improve things.
Using a 60cm dish with ~2.5deg beam width and a dual band 10/24G feed so i can line up on 10GHz signal first.
Some info here on the Rx:http://www.m0dts.co.uk/index.php?tag=24GHz&item=97
Today result after a bit of tweaking is near enough P5 signal over 28km path.
If anyone has any idea whether there's any UK records/previous activity for 24GHz ATV I'd like to know
52km test is next test then maybe 115km in the near future.
I hope to monitor signal vs weather soon to see how it's effected compared to 3cm.
Rob
M0DTS
- Attachments
-
- G1LPS 24GHz ATV 26/6/2014
- LPA 24G 26062014_small.jpg (221.85 KiB) Viewed 7229 times
Re: 24GHz dx..
Last night i went to one of my regular Portable sites with the 24GHz Rx.
Liaised with Terry on 2m talk back and he turned the 10mW Tx/Horn towards me and i received his signal up to P4 level, distance 53Km!!
We were quite amazed how well 24GHz works considering the loss, it was raining all along the path when we were running the test so losses must have been quite high.
Next is 115km test sometime in the near future!!
Rob
M0DTS
Liaised with Terry on 2m talk back and he turned the 10mW Tx/Horn towards me and i received his signal up to P4 level, distance 53Km!!
We were quite amazed how well 24GHz works considering the loss, it was raining all along the path when we were running the test so losses must have been quite high.
Next is 115km test sometime in the near future!!
Rob
M0DTS
Re: 24GHz dx..
Well done Rob
It's a band that I am interested in but at the moment
I possess no gear. I will watch progress with interest.
73's
Mike G1LWX
It's a band that I am interested in but at the moment
I possess no gear. I will watch progress with interest.
73's
Mike G1LWX
- G1LPS Terry
- Posts: 198
- Joined: Mon Mar 10, 2008 10:33 pm
Re: 24GHz dx..
Here's a picture of my basic 24GHz TX setup
- Attachments
-
- Here is my 24GHz 10mw TX with 25db Horn
- 24GHz TX 10mw.jpg (69.2 KiB) Viewed 7166 times
Re: 24GHz dx..
Fascinating, when you consider the narrow wavelength and losses being inserted along the TX/RX path it is amazing any of the actual original TX manages to make it through at all, gives food for thought at the potential of the band with half decent equipment, similar to Mike here, no gear for 24Ghz yet, barely managing to gather gear for 10Ghz myself, so will also monitor this thread for updates, well done to Rob & terry for having a dabble on 24Ghz.
Re: 24GHz dx..
Well done Rob on your 24Ghz ATV experiments. I never got up to those dizzy heights before pulling the plug on ATV.
I have a box full of 23/24Ghz bits. ex commercial. PA's , multipliers, Vco's downconverters, wg etc. I did list it all in the Forsale section last year but no takers. I will re list if anyone's interested!
I have a box full of 23/24Ghz bits. ex commercial. PA's , multipliers, Vco's downconverters, wg etc. I did list it all in the Forsale section last year but no takers. I will re list if anyone's interested!
- G1LPS Terry
- Posts: 198
- Joined: Mon Mar 10, 2008 10:33 pm
Re: 24GHz dx..
Sounds like interesting parts.
please list what you have
Thanks
please list what you have
Thanks
Re: 24GHz dx..
Hi Terry,
Ok will list again in the next few days. Better someone makes use of it than going in the Skip !
Nick
Ok will list again in the next few days. Better someone makes use of it than going in the Skip !
Nick