Last chance to get Intelsat 707 @ 53W

[Analoguesat]

The dilapidated old bird is slated for retirement in the near future, with her next trip being the final boost to graveyard orbit.

satobs.org/seesat/Dec-2012/0205.html

 

[Piltdownpaul]

Thought you were on about the Conservative Home secretary The Rt Hon. Theresa May!!!!

 

[Analoguesat]

Id make a cutting comment, but staff are supposed to keep politics off the forum

 

[Piltdownpaul]

Thats fair enough, the desire to be a politician should ban you from ever being one. Back to topic though, no chance of me getting anywhere past 30W really due to me being at the bottom of a gentle hill.

 

[Analoguesat]

I cant get past 5E due to trees.

I used to be able to get a few westerly birds by putting dishes in exact places around the garden but the trees have grown a lot in the last few years.

And no I cant get them felled!

 

[Vipersan]

Funny you should bring this one up AS..
Been trying for a couple of days to get a lock on the only other channel other than Africable available to us ..
3716 R
tp 21

Maïsha TV

Sadly below lock threshold and S2 which doesn't help..
Best I have had is about 2.5db (F15) ..and falls well short of lock..
Maybe if it had been dvbs qpsk..
Any of our intrepid UKdxers managed better ?
rgds
VS

 

[nelson_b]

Funny you should bring this one up AS..
Been trying for a couple of days to get a lock on the only other channel other than Africable available to us ..
3716 R
tp 21

Maïsha TV

Sadly below lock threshold and S2 which doesn't help..
Best I have had is about 2.5db (F15) ..and falls well short of lock..
Maybe if it had been dvbs qpsk..
Any of our intrepid UKdxers managed better ?
rgds
VS

no luck at all, with this sat position for me --

 

[Vipersan]

no luck at all, with this sat position for me --

That surprises me Nelson ..unless it's that wall again..but I assumed that only came into play at 55W..
Africable is certainly strong enough to lock on your dish I would think..
Usually about 3 > 3.5 db here and LSR DVBS QPSK..which makes the lock possible.
rgds
VS

 

[aceb]

Not checked this in the last week but I started a thread about Maisha a few weeks ago including some unusual results with the plate.

 

[aceb]

only needed to say it once!

 

[nelson_b]

That surprises me Nelson ..unless it's that wall again..but I assumed that only came into play at 55W..
Africable is certainly strong enough to lock on your dish I would think..
Usually about 3 > 3.5 db here and LSR DVBS QPSK..which makes the lock possible.
rgds
VS

the wall is the problem - i,m losing signal from 50 west -- onwards
but this is made worse as the circular C band l.n.b is offset by approx 5 - 6 degrees - so in effect to get 53 west the dish is actually pointing at 58 - 59 degrees which is my full reach west anyway
and i,m losing too much dish area by then .
so for linear sats because of the 5-6 degree offset on the linear l.n.b. - i get a slight advantage and get 55 west when in reality the dish is pointing at 49 - 50 west --

i hope i,v explained that reasonably well - l.o.l.

cheers -

 

[Huevos]

i hope i,v explained that reasonably well - l.o.l.

No, I don't get it. What does it matter where the dish is pointing. That the satellite is visible over the wall is the important thing. Or are you saying the dish is lower due to the offset so can't see over the wall so well?

 

[nelson_b]

Or are you saying the dish is lower due to the offset so can't see over the wall so well?

yes the more west i go - the lower the dish is - the less signal i get - because of the wall
so for the c band circular l.n.b. (Offset by 5-6 degrees) to receive 53 west - i have to go further west - {so lower)

 

[Vipersan]

yes the more west i go - the lower the dish is - the less signal i get - because of the wall
so for the c band circular l.n.b. (Offset by 5-6 degrees) to receive 53 west - i have to go further west - {so lower)

And I have exactly the same issues with sats beyond the Troublesome tree ie ..57 60 and 62 East ..
The further I go ..the more dish is masked as it dips..
So I know what you mean..
rgds
VS

 

[Vipersan]

Certainly something is odd with the signals coming from this bird atm..
I can't compare locked signals from Maisha ..they simply aren't strong enough here ..
But Aceb says ..the signal is present both in Right and Left circular..
Now ..taking this a step further I tuned in Africable which has always been Right Circular for me ..and at about 3.5 db max...so imagine my surprise when I casually flicked the polarity of the already stored Channel to Left circular ..and the signal level went up 2db and remained locked..
Left circular = 5.5 db ...and very solid indeed.
Tomorrow I'll retry the original DOS plate and a T Plate to compare ..
Currently using Prides New design DOS plate..
Curiouser and curiouser.
Either they are broadcasting in dual polarity ...or the sat is damaged in some way so that correct polarity cannot be achieved..??
rgds
VS

 

[nelson_b]

just dawned on me that maybe i "can" get this sat, --- if i stick a plate in the linear C band l.n.b. -
as its offset is on the other side of the dish - so i wont need to go so far west - and should "just"
avoid the wall problem --- !
not until this awful weather calms down though -- maybe tonight .

cheers --

 

[Vipersan]

Ok ..just braved the elements to nip outside and remove the plate ..so I can check Africable using a linear approach...
Checked the pretuned channel in using both H & V ..
The signals are very similar ..but fluctuate wildly from about 1db to 5 db..
I'm leaning more toward dual polarity now as this would sort of make sense..As the 2 signals ocasionally would arrive in phase or out of phase reative to each other ..thus adding of cancelling..to create an increase or decrease in signal.Such a thing isn't easy to visualise with circular polarisation..but sort of makes sense.
By inserting the plate you'd be making a concious descision to accept or reject one or t'other..but presumably there _would_ still be some interaction in front of the plate ..or point of depolarisation.
Time to ask someone more expert what the effects would be?
CH ? ...anyone ?

 

[Channel Hopper]

I would think it is something closer to home that is causing the fluctuations

Either they are broadcasting in dual polarity ...or the sat is damaged in some way so that correct polarity cannot be achieved..??
rgds
VS

Does your receiver have any incremental voltage settings for polarity ?, Have you tried turning off the 22kHz tone switching ?

 

[Vipersan]

I would think it is something closer to home that is causing the fluctuations
Does your receiver have any incremental voltage settings for polarity ?, Have you tried turning off the 22kHz tone switching ?

No to the incremental voltage settings CH..
H or V as with ku band switching..
22khz tone is off by default in Cband ...
This oddity isn't present on any other circular bird..and has been commented on already by Paul ..so I can't see how it could be local..
Oddly the signal which was and always has been Right Circular appears predominantly Left Circular..by almost double the signal level..
Nothing has been physically changed re Christina..so..I guess I'll just have to wait and see if anyone confirms my findings..
rgds
VS

 

[Vipersan]

Here are a couple of snaps showing the variation in sig level ..
All that is changed is the H or V ( Left or Right ) lnb probe selected..
Nothing physical re plate or dish.
rgds
VS