Does the Tower await me ?

Ok ..to wrap up the Saorsat phase of the experiment ..
I adapted the lnb and feed to temporarily take the Hughes depolariser ..
Tried it in 2 positions at 45 degrees to the pseudo linear inverto lnb ..
Which now has no septum so would have difficulty separating RHCP from LHCP ..
This proved to be true and the Hughes depolariser gives this ability back at least partially..
Switching the inverto electrically between RHCP and LHCP does introduce a small variance in gain ..but not enough to disprove the lnb is working in pseudo linear..
The relative positioning of the hughes depolariser makes for a dramatic variation.
Scans A and B are the inverto switched electronically with the depolariser in the first postion..
..and you clearly see ..errr ..nothing at the chosen saorsat test frequency 20185
but with the depolariser in the second position and the inverto voltage switched C and D scans clearly show a constellation much like I'd expect to see on an unmodified Inverto straight out of the box..
Similar gains ..and 2 ..possibly 3 signals/footprints overlayed at 20185..
the Saorsat signal is clearly there QPSK in the constellation ..as are t'other signals ..
hence unlockable...at my location.
Interesting to reverse engineer and experiment ..but nothing to be gained ..so will now work on moving the local osc frequency of the modded pseudo linear inverto ..and finding another use for it.
rgds
VS
 

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Well that's a pretty good effort VS, Probably the best you can do where you are at the crossroads between beams. The depolariser and LNB H/V switching obviously working OK looking at the scans.

If you do have a try at adjusting the LO of the Inverto, make sure that any nut or other object you add to the end of the screw doesn't come into contact too hard with the DRO pill when the screw is fully extended, as it could twist the DRO and possibly its base off its mounting; I've done that, but it can be glued back on with a tiny drop of superglue - there's a green printed circle to aid positioning.
 
Well ..I spent most of the afternoon looking for Sicral 1B ..
Only one transponder listed at Flysat ..20534 V
and can't find a footprint map (not listed at Satbeams)
So no idea if I'm even in with a chance ..as I may well be out of footprint.
I have managed to shift the pseudo linear inverto local osc a good bit ..err ,,lower
and because this lnb works in reverse ..was hoping this would allow me to scan higher into the next Ka band up.
Totally trial and error ..but here is 9E being scanned using crazyscan
The peak that should contain Saorsat at 20185 is theoretically now the last hump to the left of scan..thus a good spread higher than that..
Not found 20534 V of course ..but this could be
a) the frequency shift not high enough...
b) I'm actually looking at the wrong polarity..
c) the lnbs front end is finely tuned and filtering out higher frequencies..(bandpass filters)
d) I'm simply out of the footprint area..(all depends on 20534V being classed as SHF or EHF > EHF covers the UK ,,,,SHF is Italy only)
Did you have any success finding Sicral Llew ?
I'm assuming not or you would have posted something..
rgds
VS
 

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Isn't the footprint at Flysat telling enough?
With EHF, Ka-band is meant, you may well be outside the footprint that basically covers Italy.

Also, like most milsats Sicral 1B is not within a narrow +/- 0.1 degree slot.
Last reported on 1 July at 12.0 East.
 
hvdh said:
Isn't the footprint at Flysat telling enough?
With EHF, Ka-band is meant, you may well be outside the footprint that basically covers Italy.

Also, like most milsats Sicral 1B is not within in a narrow +/- 0.1 degree slot.
Last reported on 1 July at 12.0 East.
Click to expand...
I guess that was my question ..
Is SHF the Ka band I'm looking at or is it EHF ?
It's not immediately obvious from flysat.
Sicral could have another even higher band in use...or indeed SHF could be lower .. say 18ghz
cheers.
VS
 
hvdh said:
Check the wordings at http://space.skyrocket.de/doc_sdat/sicral.htm
What is considered SHF or EHF, is just as flexible as what is considered Ka- of K-band. ;)
Click to expand...
Making more sense now ..
cheers buddy ..
So I am out of footprint in Ka/EHF
Italy only ..
..and the only downlink in that part of the spectrum that I'm aware of ..so no way to test the modded inverto lnb.
cheers
VS
 
Well, it's up to you to discover! Not many will be exploring the military 20.2...21.2 GHz band.
Of course, you are checking for candidates on my site? :D
Like WGS 2 (60 E), WGS 3 (12 W), WGS 6 (52.6 W), at least they are not inclined like most others.
 
Vipersan said:
Well ..I spent most of the afternoon looking for Sicral 1B ..
Only one transponder listed at Flysat ..20534 V
and can't find a footprint map (not listed at Satbeams)
So no idea if I'm even in with a chance ..as I may well be out of footprint.
I have managed to shift the pseudo linear inverto local osc a good bit ..err ,,lower
and because this lnb works in reverse ..was hoping this would allow me to scan higher into the next Ka band up.
Totally trial and error ..but here is 9E being scanned using crazyscan
The peak that should contain Saorsat at 20185 is theoretically now the last hump to the left of scan..thus a good spread higher than that..
Not found 20534 V of course ..but this could be
a) the frequency shift not high enough...
b) I'm actually looking at the wrong polarity..
c) the lnbs front end is finely tuned and filtering out higher frequencies..(bandpass filters)
d) I'm simply out of the footprint area..(all depends on 20534V being classed as SHF or EHF > EHF covers the UK ,,,,SHF is Italy only)
Did you have any success finding Sicral Llew ?
I'm assuming not or you would have posted something..
rgds
VS
Click to expand...
No, I didn't try for Sicral when i used the modded Triax LNB, too late now the LNB is parted from its feedhorn. The only checks I did was on 16E and 7E, but I don't think my extended LO was high enough to bring in anything there, maybe because of the instability of the LO. or as you say, the bandpass filters prevented reception.
 
I have no idea what this is ..but definitely a hump in the trace ..OUTSIDE (higher frequency) the normal inverto range.
Somewhere in the region of 20200 I would guesstimate..
Nothing intelligible or lockable ..
not even sure of polarity ?
Possibly linear ?
but it is real ..
If I move Carl off target 10 clicks either way ...I lose it ..
roughly 12W so maybe from WGS3 ??
rgds
VS
 

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2 more massive unlockable data peaks ??
these are coming from 38 East approx. ..
again ..outside the normal inverto range and appearing on both H and V traces ..through one hump dominant in each..
Might try rotating the lnb to check for changes in signal level..
this would in theory give a better indication of linear/circular..
but no idea what they are..
just know they are above 20200
rgds
VS
 

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Vipersan said:
I have no idea what this is ..but definitely a hump in the trace ..OUTSIDE (higher frequency) the normal inverto range.
Somewhere in the region of 20200 I would guesstimate..
Nothing intelligible or lockable ..
not even sure of polarity ?
Possibly linear ?
but it is real ..
If I move Carl off target 10 clicks either way ...I lose it ..
roughly 12W so maybe from WGS3 ??
rgds
VS
Click to expand...
I've had that one at 12W VS, I think with the Hughes LNB (?), definitely out of the Inverto range. Not sure if I took a scan pic of it, trying to find it ATM.
 
I'll check tomorrow with the Promax on the Hughes and check the actual frequency.
 
Hi Llew ..
If these are as HVDH has suggested ..military downlinks..then chances are they wouldn't be lockable ..
ie not DVBS standard.
I'll try and create a more accurate trace tomorrow..
but will only be an approximation as the only reference I have is that multi beam transponder on the Saorsat frequency 9E
rgds
VS
 
Llew said:
I'll check tomorrow with the Promax on the Hughes and check the actual frequency.
Click to expand...
That would be helpful Llew ..
Perhaps you could check the 2 at 38East approx. also ..assuming you can get line of sight.
cheers
VS
 
Don't think I can do 38E with the Triax dishes VS, only with the Gibby, and I don't really want to put the Hughes assembly on that because of the dodgy Epoxy'd fixing of the feedhorn to the depolariser :(
 
Llew said:
Don't think I can do 38E with the Triax dishes VS, only with the Gibby, and I don't really want to put the Hughes assembly on that because of the dodgy Epoxy'd fixing of the feedhorn to the depolariser :(
Click to expand...
Fair enough Llew ..
The 12W frequency will suffice as I can hopefully set up an accurate trace with a custom LO ..
rgds
VS
 
Thanks for the info once again hvdh ...much appreciated ..
at least I have a couple of targets now to point my modded inverto at ..
;)
 
sonnetpete said:
"Restrictions on melting or breaking of metal coins..

Defacing by drilling a hole through the coin (and through the Queen's head) would count as destruction.
Click to expand...

Flattening coins appears to be legal, and I'm certain the machine - the one in the science museum at least - removes the original detail.


http://en.wikipedia.org/wiki/Elongated_coin

It's not far off paying a pittance to sit on the Queens face,
 
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