The Aero Thread..

[s-band]

fwiw I went in earch of the Aero signals on 25E ....
I found em I think ...but they are at lower levels to those at 15W so wont produce lockable Data on 10500 ....
At first I did head East ..and on the way found some huge signals (non Aero) coming from something ...and in the same part of the spectrum frequency wise (L band) ...
any Idea what I might be looking at ..
Too dark to go out and get rough bearings ..but I'd guess about 4E
I'll try and grab a Spectrum spy pic ...as some are constant and wide enough to show up ..
rgds
VS

It's only the narrow band sigs that are very loud from 25E, 10500 are the same level as on 15W. I have a feeling you have highlighted the narrow band sigs from 25E on mystery2.png. I can see those sigs more of less anywhere I point an antenna. Have a close look and see if JAERO will decode the lowest of the group (600bps). The frequency is suspiciously close to pics 2-4 here: The Aero Thread..

Two things from your wide sweep:
1 Some of your problems may be from overload at low frequencies. The signals there are quite high, The helical is quite effective there and the LNA4ALL has higher gain at the LF end. A simple high pass (or band pass) filter may do the trick.
2 The step change at the high frequency end is where the R820T loses lock, I think.

 

[Vipersan]

Time to play out again ..
The USB 2.0 repeater cable just arrived ..
fully screened and well made with ferrites either end..

 

[Vipersan]

Impatient as ever ..just hung the 20mtr repeater cable out the window ..with Airspy outside on the Helical ..
Pics to follow ..
Here is my first screen grab of the target data ..
;)

 

[Vipersan]

The Helical is now on a 1 mtr test rig pointing at 15W ..
The Airspy is directly connecten to the LNA ..
no cable involved here..

 

[Lazarus]

You need a bigger yard.

 

[Vipersan]

You need a bigger yard.

Cant Argue with that G ..
Certainly I need a tidy up at least ...but I get too busy to clean ..
lol

 

[Vipersan]

Actually ..
Still cannot lock the 10500 streams ..
The 600 stuff locks solid now ..
I suspect I may still need a bigger dish ...or some serious tweaking..

Watching Jaero constellation monitor ..
Very Very occasionally evidence of QPSK seen ...but it aint constant..
doh!

 

[Vipersan]

Might as well make a brew with my UK 3kw kettle and go watch PMQs ..
RAIN STOPPED PLAY AGAIN !!

 

[Lazarus]

Make sure to fill that Water Otter to the brim.

 

[Vipersan]

Make sure to fill that Water Otter to the brim.

Does that suggest the rain is in for the day ??
I suspect I'll get through a few Mugs 'o' T then ..
lol

btw ..quick question ..
anyone any idea where I might purchase a 28.8 mhz TCXO (must be SMD) ?
Has the entire world stock been bought up by NooElec ?

 

[s-band]

Does that suggest the rain is in for the day ??
I suspect I'll get through a few Mugs 'o' T then ..
lol

btw ..quick question ..
anyone any idea where I might purchase a 28.8 mhz TCXO (must be SMD) ?
Has the entire world stock been bought up by NooElec ?

I couldn't find one. The Mouser/Digikey stock is poor stability. I bought one of these 1 pcs TCXO 28.8MHz 28.800M Ultra precision Crystal Oscillators DIP 0.5ppm(NT) but haven't tried it yet. It's not much more to buy a dongle with one already fitted. You can get some very good, cheap 14.4MHz OCXOs which can be doubled but that will end up large.

Looking at your JAERO I'm not sure it can work like that (mine's not set up to test it now). Try Tools > settings > Enable widebandwidth (check box) then, tune so that the signal is in the middle of the detector window as here: https://www.satellites.co.uk/forums/attachments/15w_helical_10500_gaas_lna-png.93654/

 

[Vipersan]

I'll try it later SB ..
got to go to work now ..
sadly in the rain again..

 

[Vipersan]

I couldn't find one. The Mouser/Digikey stock is poor stability. I bought one of these 1 pcs TCXO 28.8MHz 28.800M Ultra precision Crystal Oscillators DIP 0.5ppm(NT) but haven't tried it yet. It's not much more to buy a dongle with one already fitted. You can get some very good, cheap 14.4MHz OCXOs which can be doubled but that will end up large.

Looking at your JAERO I'm not sure it can work like that (mine's not set up to test it now). Try Tools > settings > Enable widebandwidth (check box) then, tune so that the signal is in the middle of the detector window as here: https://www.satellites.co.uk/forums/attachments/15w_helical_10500_gaas_lna-png.93654/

Just got home and first thing I checked ..
I already have wideband enabled in Jaero..

 

[s-band]

Just got home and first thing I checked ..
I already have wideband enabled in Jaero..

I think your BW must be restricted then. Have you got the audio BW set to 16kHz?

 

[Vipersan]

I think your BW must be restricted then. Have you got the audio BW set to 16kHz?

Sorry to sound thick ..but where would I check and if neccessary adjust this ?

Is it a function of SDR# or a PC o/s setting ?

 

[s-band]

Sorry to sound thick ..but where would I check and if neccessary adjust this ?

Is it a function of SDR# or a PC o/s setting ?

In SDR# "Radio" tab set bandwidth to 16000

 

[Vipersan]

In SDR# "Radio" tab set bandwidth to 16000
View attachment 93811

In which case I probably had this wrong ....set to 10500 ...
I assumed this was correct ??
obviously not ..
..but opening this up to be wider than Jaeros setting of 10500 centres the signal ..but sadly still no QPSK in the constellation window ...and no data..
Perhaps best tried on a less wet day ..

 

[Vipersan]

 

[s-band]

In which case I probly had this wrong ....set to 10500 ...
I assumed this was correct ??
obviously not ..
..but opening this up to be wider than Jaeros setting of 10500 centres the signal ..but sadly still no QSP in the constellation window ...and no data..
Perhaps best tried on a less wet day ..

JAERO doesn't work down to DC hence keeping the signal above the bottom edge. If it's centring it the AFC must have locked, you're close. Mine was just decoding at around 3-4bB EbNo. Comparing my ones on the helical to yours you are a dB or 2 short. Try tweaking the gain and volume just in case you can scrape a bit.

 

[Vipersan]

So ..spent a whole day on this ..out in the sunshine ..
glorious ..and barely a cloud ..
Moved the Helical back to the 1.5m ..(Carl)
Fitted the LNA4ALL in one of those neat black ally boxes I got from China..
but not before I upped the value of the cap on the input coupling the Helical element ..
No idea what it is/was ..but added another 680 pf in parallel..
Still using Airspy at the antenna ...and the 20mtr screened USB repeater ...
If it stays nice tomorrow ..I hope to move the Helical back to the 1mtre dish to see if I can lock ...well ...anything really from the 10500 streams at 1.546.050
But ..I got mt first taste of data ...
So ..that will drive me on ...
Gutted though that the only way forward might be to include the Airspy inside the Helical die cast back box ..
Pity I can't use a cheap RTL dongle for this job ..rather than tie up Airspy in this way ..
Expensive hobby this is ..fer sure..
rgds
VS