The Aero Thread..

Slightly OT

Has anyone tried ShipPlotter? ShipPlotter
 
26542380011_ec5f81b444_b.jpg



The image above shows just satellite and PiRep plots from Oceanic traffic . As you can see , it's pretty busy.
At present we don't have anyone uploading from the USA and as a result are missing traffic from two westerly birds, but I am hoping that will be addressed this weekend.
There are some very interesting movements , which until now have gone unnoticed , including top level mil/DoD flights from the US to central Africa[Chad]
Last weekend we had all the Obama circus fleet appearing .

Thanks to the likes of "C" , Scopus , Paul , Andy and our other satellite stations we are now seeing 20,000 unique position plots for Oceanic traffic each day.

The next version of PP will be released shortly which will contain even more enhancements and allow us to separate PiRep and satellite traffic. Updates are of course free to registered users.

On the subject of inclination , I agree with VS about dish size.
My 1.8 can just about maintain a useable signal on 25east which is just under 2 degs inclined....but for anything with a bigger "wobble" the 1.2 should be better , even though you'll see some missed/bad packets.
 
My 3Rd TiT C1W-pll Lnb arrived today, this one for 15W. silly question, does anyone know what the strip of black rubbery tape is for?
 
My 3Rd TiT C1W-pll Lnb arrived today, this one for 15W. silly question, does anyone know what the strip of black rubbery tape is for?
 
Its a piece of self amalgamating tape to waterproof your F connector .
 
spacedish said:
Its a piece of self amalgamating tape to waterproof your F connector .
Click to expand...
Ahhhh I see, I thought it might be important !!!! lol
I used heat shrink and a blob of grease.
 
Next Question
How far into the conical scalar should the Lnb go. ?
Is there a "formula or is it "poke & hope" ?

DSC_0047.webp
 
Depends on the FD ratio of the dish, I always employ the 'poke and hope' method, seems to work for me;)
 
Confucian said:
Next Question
How far into the conical scalar should the Lnb go. ?
Is there a "formula or is it "poke & hope" ?
Click to expand...
IMO, the position of the feed phase centre, relative to the dish focus, is the most important thing with the scalar position secondary.

I use EBSPRO's Android app and tweak the position of the feed/scalar. If there's nothing that EBS can work with, I use an Android VNC client (RealVNC) to view the beacon level on SDR# running indoors.

Having said all that, poke & hope seems to get within a dB half the time.

Edit - another couple of things that may give you an extra dB or 2:
Try both polarisations moving the plate to get the right sense of circular
Also move the dielectric plate in and out to optimise signal
 
Last edited:
[QUOTE="scopus, post: > I always employ the 'poke and hope' method, seems to work for me;)[/QUOTE]<
... I'm saying nowt :D
 
Last edited:
s-band said:
Try both polarisations moving the plate to get the right sense of circular
Click to expand...

Sorry for being dim how do you mean "moving the plate to get the right sense of circular"
 
Last edited by a moderator:
how do you mean "moving the plate to get the right sense of circular"


Switch polarisation electrically (V to H or vice versa) then turn the plate 90 degrees, looking at the open waveguide. That way you will keep the same circular polarisation but swap the front end electronics/feed. Usually there is a slight difference in performance between V & H electronics/feeds.
 
Yet more thoughts....
The scalar ring is mainly to improve the front to back ratio of the feed and to reduce spill over where the feed "sees" ground noise if it covers more than the dish area (especially for PF). In the case of the offset it needs to reduce the beam a bit more than a PF. I guess that for an offset the feed needs to be well inside the scalar. In setting the scalar, it may be better to use the EBSPro route as you can measure S/N directly and it's the N that the scalar will affect most.

If you want the last 0.1dB, it may be worth raising the dish above the building so that any overspill "sees" cold sky as opposed to a warm building.
 
Last edited:
s-band said:
how do you mean "moving the plate to get the right sense of circular"


Switch polarisation electrically (V to H or vice versa) then turn the plate 90 degrees, looking at the open waveguide. That way you will keep the same circular polarisation but swap the front end electronics/feed. Usually there is a slight difference in performance between V & H electronics/feeds.
Click to expand...

Ah Ha That explains why when I first started looking for 25E I "Theoretically" correctly set the polarization with the Receiver but had to reverse it to get the Channels.
Also the "IF" there isn't any/much difference in the front end electronics I could get away with one psu feeding via 3 x Bias Tee's and set the polarizations with the wedges ????????????
 
Confucian said:
Also the "IF" there isn't any/much difference in the front end electronics I could get away with one psu feeding via 3 x Bias Tee's and set the polarizations with the wedges ????????????
Click to expand...
Yes. Alternatively, use an 18V PSU feeding a 12 V regulator (e.g. 7812) to get both voltages.
 
Confucian said:
Airspy Mini
Click to expand...
Interesting. The back end specification is subtly different from the R2 and the deal breaker for me is that it doesn't appear to have an external reference input. The upgraded RTL-SDRs with 0.5ppm TCXOs may be better value for sat use.
Worthy of a new thread?
 
Back
Top