The Aero Thread..

So small update on this one
Ive managed to decode the data and as side information the adalm-pluto looks a little bit more sensitive
 
Inmarsat-3 F2 is leaving 15.5°W, drifting 1°W/day.
Launched in 1996, probably end-of-life but orbit should be raised some more.
 
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I guess that is why I can no longer receive anything on my L Band helical antenna..
I recently had time to fire it up ...and received zip..
Like a fool I got ladders out and brought the Helical/LNA/RTL dongle antenna down from the dish for checking ..cleaning and new sealant.
But still nothing ..
So ..no more Inmarsat 15.5W L band experiments ..?
Unless I can still receive this bird at whatever location it ends up ??
any info appreciated ...as I rarely get time to play out any more.
rgds
VS
 
...I also bought one of these recently cheap off ebay ..
Vaisala RS80-15GH Weather GPS Radiosonde

and ordered a Pre-filtered GNSS LNA GPS L1-L5 GLONASS BeiDou Navic Amplifier 27dB w/ BIAS TEE

from Canada.. (another few weeks to wait for this)
The intention is to rob the QFH GPS antenna off the Radiosonde ..and use it in conjunction with the Navic LNA ...

Why ..?
well L-band circular polarised omnidirectional reception..

Now I'm thinking I may well have wasted time and money if there is nothing to receive..

cest la vie
 
Vipersan said:
I guess that is why I can no longer receive anything on my L Band helical antenna..
I recently had time to fire it up ...and received zip..
Like a fool I got ladders out and brought the Helical/LNA/RTL dongle antenna down from the dish for checking ..cleaning and new sealant.
But still nothing ..
So ..no more Inmarsat 15.5W L band experiments ..?
Unless I can still receive this bird at whatever location it ends up ??
any info appreciated ...as I rarely get time to play out any more.
rgds
VS
Click to expand...
Good to see you here again. I haven't looked at L band for a long time but have you tried Alphasat 25E?
 
s-band said:
Good to see you here again. I haven't looked at L band for a long time but have you tried Alphasat 25E?
Click to expand...
TBH ...this one may only be visible until my troublesome tree leafs up ..but might be worth a go ...if it hasn't moved.

..so what do you think of my new mini QFH project ?
viable ?
I may need some help getting them impedance matched ...and you are the guy to ask.
lol
rgds
 
Vipersan said:
...I also bought one of these recently cheap off ebay ..
Vaisala RS80-15GH Weather GPS Radiosonde

and ordered a Pre-filtered GNSS LNA GPS L1-L5 GLONASS BeiDou Navic Amplifier 27dB w/ BIAS TEE

from Canada.. (another few weeks to wait for this)
The intention is to rob the QFH GPS antenna off the Radiosonde ..and use it in conjunction with the Navic LNA ...

Why ..?
well L-band circular polarised omnidirectional reception..

Now I'm thinking I may well have wasted time and money if there is nothing to receive..

cest la vie
Click to expand...



Hello stranger! :)
 
Hi Gordon ..
Yes I am a stranger these days ..
My situation is much the same ..if not worse .
mums dementia takes priority and demands so much from me ..that my health is adversly affected.
I do try to keep my mind active ..even though physically I'm wrecked.
cheers buddy
Evan
 
Good to see you back Evan even if it is just for a quick visit.

. Ive missed your weird & wonderful discussion threads.
 
Analoguesat said:
Good to see you back Evan even if it is just for a quick visit.

. Ive missed your weird & wonderful discussion threads.
Click to expand...
Weird and wonderful is my mojo...
I just dont like the idea that old equipment is retired ...
New equipment is in house and proprietory ..
signals are encrypted or inaccessible.
curiosity is key..
and an inquisitive mind is a wonderful thing.
nuff said.
lol
 
Vipersan said:
Weird and wonderful is my mojo...
I just dont like the idea that old equipment is retired ...
New equipment is in house and proprietory ..
signals are encrypted or inaccessible.
curiosity is key..
and an inquisitive mind is a wonderful thing.
nuff said.
lol
Click to expand...


I think most of us on here share similar traits...........
 
Chris1979 said:
I think most of us on here share similar traits...........
Click to expand...
Hi Chris ..
last time I checked in you too appeared to be AWOL ...
how yer doing buddy..??
rgds
Evan
 
Vipersan said:
TBH ...this one may only be visible until my troublesome tree leafs up ..but might be worth a go ...if it hasn't moved.

..so what do you think of my new mini QFH project ?
viable ?
I may need some help getting them impedance matched ...and you are the guy to ask.
lol
rgds
Click to expand...
I had a quick look at 25E but using the S band front end and feed on a 1.2m. Both feed and LNA have drooped a bit by 1500MHz but Alphasat is there. The 2nd plot looks a bit like aero but it doesn't tie up with Jonti's site. However, that could be old info.

25E_SA_PNG_000050.webp25E_SA_PNG_000049.webp

Curiously I found another big L band thing at about 45E. At L band the direction finding ability is poor though but it is probably within 2-3 degrees It's much stronger but is mainly pulsed signals. See plot where yellow is real time and green is max held. Any ideas @hvdh ?

45E_SA_PNG_000047.webp

I'm not sure you'll get enough s/n from a QFH but anything is worth a try. Find something using your helical first though. e-mail if you have questions.

<edit> I just found these in the archive from May 2016 on 25E:

25E_helical_600bps_gaas_lna.webp25E_helical_600bps_gaas_lna.webp25e_helical_10500_gaas_lna.webp
 

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Vipersan said:
Hi Chris ..
last time I checked in you too appeared to be AWOL ...
how yer doing buddy..??
rgds
Evan
Click to expand...


Not to bad now thanks, glad to see you back on the forum.

Hopefully things will pick up for you soon (fingers crossed)
 
Hey hey Evan, good to hear from you.

Do you have time to look after the herd while I take my annual bath ?
 
Chris1979 said:
I think most of us on here share similar traits...........
Click to expand...

Indeed - Ive bought an old "builders wheelbarrow" back from the allotment this afternoon - in the hope of doing some sort of basic restoration on it over the summer. It was extremely secondhand when we got given it and its been sitting outside in the Scottish weather for at least 3 years. I may do a thread on it when I finally get around to it! :D
 
Analoguesat said:
Indeed - Ive bought an old "builders wheelbarrow" back from the allotment this afternoon - in the hope of doing some sort of basic restoration on it over the summer. It was extremely secondhand when we got given it and its been sitting outside in the Scottish weather for at least 3 years. I may do a thread on it when I finally get around to it! :D
Click to expand...
:-lmao:-rofl2
 
hvdh said:
Inmarsat-3 F2 is leaving 15.5°W, drifting 1°W/day.
Launched in 1996, probably end-of-life but orbit should be raised some more.
Click to expand...
Here is a pdf about all the recent migration changes:
www.inmarsat.com/wp-content/uploads/2018/08/Aero_Service_External_Com_Kit_I3_to_I4_Transition_21AUG2018.pdf
So Inmarsat does not use 15.5°W any more. L-band services must have moved to either Alphasat (24.85°E) or Inmarsat-3 F5 (54.0°W).

The old F2 is still drifting 1°W/day, now near 33°W.
If not end-of-life (with bad orbit raising), maybe can become an in-orbit spare for a while.
 
Thanx for the pdf Hvdh ...
I guess I will have to point my helical at 54w now ..
What was not crystal clear from reading ..
is it a question of waiting for sat movement and relocation ..or is this just a switch of services to a different bird. (3 F5)
That said ...if F2 is nearing life end and unable to maintain solid geo orbit ..is it just being moved to 54W as a backup for 3 F5 ?
rgds
VS
 
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