some progress


Robert Moore
 

While it’s very disappointing to be without access to all the good things coming down from Eutelsat 10A and data yet to come, nevertheless I do have some reception at 6.2 SNR. HRIT images are being received with an occasional whole image missing and a few chunks missing from the some of the received images. Thus I can get two or three good images in GSS morning and afternoon. Enough also for convection and air mass imagery. Very much better than nothing. Frustrating not to have GOES-16 for a complete picture of the north Atlantic.

Anyone passing this way with a long ladder and a head for heights welcome to try to improve my reception!

Robert

 


Ernst Lobsiger
 

Robert,

you can either stay with your 'grown tree' theory or still try points below if not already tried.
Most of the advice has been given to you before but I'd like to sum up my two cents here:

1) I *doubt* that "a few centimeters" of grown trees make an SNR difference of 6 versus 14dB
2) An SNR of 6.2dB will give you no useful results as BASIC channels have link margin 0.3dB
   while HVS-1 has link margin -3.1dB ! That said you certainly filter out HVS-1 MODCODs ?
3) Regarding 2) maybe you find someone that can check this with an independant TC receiver.
4) There is a rare possibility, that happened to me at least once, that you receive the signal
   via a first antenna sidelobe. This can happen if your first azimuth estimate is by compass.
   Then you optimize for hours (as I did) your first sidelobe without knowing what's going on.
5) Regarding 4) you should check the antenna azimuth using the sun. For this find someone
   that spans a 1/2 inch black plastic tape from the LNB center to the exact top of the antenna.
   Then check or photograph the shadow of this tape on the dish at the time when the sun
   exactly passes the azimuth that your antenna should have. Needless to say that this shadow
   should/must fall on the center of your dish and that you find the sun passing time on the net.
6) At the very time of the next solar outage try to observe or even photograph the sun from
   near your antenna. To protect your bare eyes you can use some of these electric welding
   filter glasses. The apparent diameter of the sun is 0.53° (32'). So this will allow for
   a very exact estimate of your (hopefully?!) remaining gap over the top of the trees.
7) Finally the attached image of your (old) antenna shows a long gutter rather close. If
   this gutter is metallic and electrically conducting (as the image seems to show) then
   this might deteriorate the antenna position or at least have an influence regarding 4).
8) If you'll ever have your antenna repointed, make sure you have life feedback of SNR from
   your TC receiver. Cheap chinese antenna pointing devices cannot handle SNR of VCM signals.

May I add that I have pointed 10+ EUEMETCast dishes myself and know what I'm talking about.


Good luck,
Ernst

 


Robert Moore
 

Thanks Ernst, I’m very grateful for your expert advice (and patience). My guttering, BTW, is plastic.

The real bugbear with this is access, I don’t have a long enough ladder now the dish is much higher. If I had a ladder that long my wife would not let me use it! So, I’m always dependent on TV engineers coming to help. The last one was very good, he read the relevant EUMETSAT document and spent hours on my roof. I don’t know about the accuracy of his TC receiver – it was certainly a large and expensive-looking bit of kit.

He was so upset at not finding a better SNR that he refused to charge me for all the hours he spent on my roof. He did, however, recommended another engineer, a newcomer to our town, I am going to follow this up.

I think your rare possibility (4) is a contender, we spent a great deal of time moving the dish by millimetres, perhaps had we been bolder we would have found a better signal. Not having access myself is immensely frustrating – if I had a clear view from ground level I could have sorted this out myself.

I did all the work on installing and aligning my NOAA tracking dish, but I had access from a flat roof. That system has all been dismantled now but EUTELSAT 10A is not visible from there although the pole for mounting a dish is still in place..

There are by the way people in our area who cannot get satellite TV because of the trees.

I shall press on, maybe with a new engineer.

Robert

 

 

From: MSG-1@groups.io <MSG-1@groups.io> On Behalf Of Ernst Lobsiger via groups.io
Sent: 19 June 2022 13:28
To: MSG-1@groups.io
Subject: Re: [MSG-1] some progress

 

Robert,

you can either stay with your 'grown tree' theory or still try points below if not already tried.
Most of the advice has been given to you before but I'd like to sum up my two cents here:

1) I *doubt* that "a few centimeters" of grown trees make an SNR difference of 6 versus 14dB
2) An SNR of 6.2dB will give you no useful results as BASIC channels have link margin 0.3dB
   while HVS-1 has link margin -3.1dB ! That said you certainly filter out HVS-1 MODCODs ?
3) Regarding 2) maybe you find someone that can check this with an independant TC receiver.
4) There is a rare possibility, that happened to me at least once, that you receive the signal
   via a first antenna sidelobe. This can happen if your first azimuth estimate is by compass.
   Then you optimize for hours (as I did) your first sidelobe without knowing what's going on.
5) Regarding 4) you should check the antenna azimuth using the sun. For this find someone
   that spans a 1/2 inch black plastic tape from the LNB center to the exact top of the antenna.
   Then check or photograph the shadow of this tape on the dish at the time when the sun
   exactly passes the azimuth that your antenna should have. Needless to say that this shadow
   should/must fall on the center of your dish and that you find the sun passing time on the net.
6) At the very time of the next solar outage try to observe or even photograph the sun from
   near your antenna. To protect your bare eyes you can use some of these electric welding
   filter glasses. The apparent diameter of the sun is 0.53° (32'). So this will allow for
   a very exact estimate of your (hopefully?!) remaining gap over the top of the trees.
7) Finally the attached image of your (old) antenna shows a long gutter rather close. If
   this gutter is metallic and electrically conducting (as the image seems to show) then
   this might deteriorate the antenna position or at least have an influence regarding 4).
8) If you'll ever have your antenna repointed, make sure you have life feedback of SNR from
   your TC receiver. Cheap chinese antenna pointing devices cannot handle SNR of VCM signals.

May I add that I have pointed 10+ EUEMETCast dishes myself and know what I'm talking about.


Good luck,
Ernst

 


Robert Moore
 

Ernst, Further to my last, here is a picture of my dish’s location.

 

Robert

 


Ernst Lobsiger
 

Robert,

unless I missed a (partly?) hidden clamp even after zooming into this image, it shows for me a 1m dish on a 3m free running pole. If you cannot prove me wrong with another image then -- not regarding your very low SNR and all that has been said and adviced before --- this can never fly because of bending and torsion oscillations if you have the slightest wind.

What is the diameter and material of the pole and how long is the verically unclamped run (that I tried to mark with red editing your image with paint) to the antenna mount?

Ernst


Robert Moore
 

One reason why I was very anxious as my first engineer went higher and higher before finding a signal. The height you marked is 1.8 metres, the pole is a standard scaffolding pole: 50 mm diameter hollow steel 2 mm thick (see diagram).

Thanks Ernst

Robert

 

 

From: MSG-1@groups.io <MSG-1@groups.io> On Behalf Of Ernst Lobsiger via groups.io
Sent: 19 June 2022 16:41
To: MSG-1@groups.io
Subject: Re: [MSG-1] some progress

 

Robert,

unless I missed a (partly?) hidden clamp even after zooming into this image, it shows for me a 1m dish on a 3m free running pole. If you cannot prove me wrong with another image then -- not regarding your very low SNR and all that has been said and adviced before --- this can never fly because of bending and torsion oscillations if you have the slightest wind.

What is the diameter and material of the pole and how long is the verically unclamped run (that I tried to mark with red editing your image with paint) to the antenna mount?

Ernst


Ernst Lobsiger
 

Sorry, I was deceived by the perspective of your image. Measuring now in pixels and remembering you had a 1 meter dish gives me 2.1 meters so your 1.8 meters seem to be real.

https://groups.io/g/MSG-1/message/33084
"
So, two questions; could I expect any improvement with a larger dish? I am currently at one metre and have room to go a bit larger.
"

BUT I'm afraid that 1.8 meters free running pole length for a 1 meter antenna and your pole dimensions is still far too much. The highly praised Gibertini OP-125L (1.25m dish) I use takes poles from 55mm (for short poles) up to 100mm for situations like yours. So when you said the wind bends the trees disturbing your reception this was probably also due to antenna torsion oscillations. That is something you can possibly check with your bare eyes or by making a video with your smart phone next time you have some stronger winds. The video can then be analyzed picture by picture on a PC ...

Regards,
Ernst


George Sz
 

That's a completely unobstructed view so there should be no issues here. That pole should be fastened more firmly indeed though. Make sure it's unable to rotate around its axis and try to add another fastener under the rain gutter. From this perspective, the dish could even be lowered, I think.

My theory is that you're not receiving the correct satellite (9°E is pretty close). My sat meter for instance has difficulty of locking onto Eumetsat's transponders due to the special modulation used, so another one should be used here for measurement. Maybe your tech guy did not have his meter set up correctly? There's not much TV to watch on 10°E so usually TV installer guys don't have this in their sat meters. Where are you located? I have a friend near London and maybe he could try. I can explain to him exactly what to do.


Ernst Lobsiger
 

George,

mind the english weather. The horizon on this image is probably hidden by the clouds. In an earlier message Robert said:

"
I suspect the ‘radiating leaves’ are playing a leading role in my problems. I always thought the height of the trees was rather marginal, I need a dish elevation of 27.9 degrees, the treetops were around 24 to 26 degrees last summer when I hoped they had reached their mature heights.
"

Ernst


George Sz
 

Ernst,

From the picture attached, the trees indeed look like they're at 25° of elevation from the camera's position, however from the top of the pole they'd be more like 5°. Maybe the picture exhibits some sort of optical illusion which makes the perceived perspective wrong, I don't know. From that height there should be no obstruction at all, or at least my eyes tell me so (or they're deceived so).

George


Ernst Lobsiger
 

On Sat, Jul 2, 2022 at 03:47 AM, George Sz wrote:
From the picture attached, the trees indeed look like they're at 25° of elevation from the camera's position
George,

it is my understanding that the trees you see in the picture are not the trees Robert Moore suspects to be the problem. These latter trees are either hidden in the fog or the image is taken at a much steeper elevation than the antenna elevation. It would help if Robert could post an image from behind the antenna where the antenna mount (center of the antenna as seen from the camera) is exactly at elevation 27.9° and azimuth 162.4° as calculated for his village and E10A. Given the height of the antenna mount over ground the distance behind the antenna can easily be calculated by basic trigonometry. If such a picture can be taken in fine weather we should see the horizon. Robert lives in Carmel North Wales. On google maps you can see that the view is uphill in direction south east.

Ernst


Robert Moore
 

Unfortunately, Ernst I cannot do this. While I have a remote release for my camera, I do not have a means of getting the camera to the height of the dish. I have a new engineer coming who is said to know more about ‘these sort of things’, when he’s up his ladder I will ask him to take the picture you suggest (actually, I’ll ask him before he’s up the ladder!)

I am still getting good HRIT reception at present with very few images missing. No strong wind recently, currently zero to 5 m/s.

 

Robert

 

 

From: MSG-1@groups.io <MSG-1@groups.io> On Behalf Of Ernst Lobsiger via groups.io
Sent: 02 July 2022 12:44
To: MSG-1@groups.io
Subject: Re: [MSG-1] some progress

 

On Sat, Jul 2, 2022 at 03:47 AM, George Sz wrote:

From the picture attached, the trees indeed look like they're at 25° of elevation from the camera's position

George,

it is my understanding that the trees you see in the picture are not the trees Robert Moore suspects to be the problem. These latter trees are either hidden in the fog or the image is taken at a much steeper elevation than the antenna elevation. It would help if Robert could post an image from behind the antenna where the antenna mount (center of the antenna as seen from the camera) is exactly at elevation 27.9° and azimuth 162.4° as calculated for his village and E10A. Given the height of the antenna mount over ground the distance behind the antenna can easily be calculated by basic trigonometry. If such a picture can be taken in fine weather we should see the horizon. Robert lives in Carmel North Wales. On google maps you can see that the view is uphill in direction south east.

Ernst


George Sz
 

I was actually wrong about my sat meter, which is happy to lock onto one of the Eumetcast TPs. However, a "normal" meter will definitely lock onto the following frequencies.

11222 V DVB-S2 QPSK 30000 5/6 - BFBS
11346 H DVB-S QPSK 33000 2/3 - AFP

By scanning the BFBS TP, the tech guy should be able to confirm he's on the right satellite. BBC etc. should be there. It's encrypted so don't expect video. See the full list here.

I'm also attaching a few screenshots from my sat meter below.
BFBS
 

AFP
 


George Sz
 

Ugh, I posted the wrong parameters for AFP because I was distracted while editing my message, sorry about that.

11346 H DVB-S QPSK 27500 3/4


Ernst Lobsiger
 

On Sat, Jul 2, 2022 at 04:56 AM, Robert Moore wrote:
Unfortunately, Ernst I cannot do this. While I have a remote release for my camera, I do not have a means of getting the camera to the height of the dish.
Robert,

nobody asked you to climb on a ladder. All you must know or be able to measure is the distance h from the height of your eyes to the antenna clamps. Then you go a horizontal distande d = 1.8886 times h behind (room and flat terrain assumed) your antenna mast. The antenna pole must appear from the position of your camera at 162.4° azimuth. You can also use your compass and inclinometer to aim to the mast and dish center from the camera position. Maybe you could put your camera on a tripod and calculate distance d accordingly. No fog or low clouds allowed: On the picture we want to see these disturbing trees or the horizon (hopefully below your antenna center).

Best regards,
Ernst


Robert Moore
 

Oh… if only, Ernst. Many moons ago when I was first setting up, I thought of this method roughly to test feasibility of reception. Here’s the problem (attached). I suppose we all feel sometimes that we could walk on water – but never on air!

 

Robert

 

 

 

 

 

 

 

 

 

 

 

 

 

From: MSG-1@groups.io <MSG-1@groups.io> On Behalf Of Ernst Lobsiger via groups.io
Sent: 02 July 2022 14:11
To: MSG-1@groups.io
Subject: Re: [MSG-1] some progress

 

On Sat, Jul 2, 2022 at 04:56 AM, Robert Moore wrote:

Unfortunately, Ernst I cannot do this. While I have a remote release for my camera, I do not have a means of getting the camera to the height of the dish.

Robert,

nobody asked you to climb on a ladder. All you must know or be able to measure is the distance h from the height of your eyes to the antenna clamps. Then you go a horizontal distande d = 1.8886 times h behind (room and flat terrain assumed) your antenna mast. The antenna pole must appear from the position of your camera at 162.4° azimuth. You can also use your compass and inclinometer to aim to the mast and dish center from the camera position. Maybe you could put your camera on a tripod and calculate distance d accordingly. No fog or low clouds allowed: On the picture we want to see these disturbing trees or the horizon (hopefully below your antenna center).

Best regards,
Ernst


Robert Moore
 

Ernst, This won’t help anyone very much, but this is the view from a little down my road, roughly now at the height of the dish, which is pointing over my right shoulder. All the installers have said that they get best SNR when lined up low in the notch between the trees.

Robert

 

 

From: MSG-1@groups.io <MSG-1@groups.io> On Behalf Of Ernst Lobsiger via groups.io
Sent: 02 July 2022 14:11
To: MSG-1@groups.io
Subject: Re: [MSG-1] some progress

 

On Sat, Jul 2, 2022 at 04:56 AM, Robert Moore wrote:

Unfortunately, Ernst I cannot do this. While I have a remote release for my camera, I do not have a means of getting the camera to the height of the dish.

Robert,

nobody asked you to climb on a ladder. All you must know or be able to measure is the distance h from the height of your eyes to the antenna clamps. Then you go a horizontal distande d = 1.8886 times h behind (room and flat terrain assumed) your antenna mast. The antenna pole must appear from the position of your camera at 162.4° azimuth. You can also use your compass and inclinometer to aim to the mast and dish center from the camera position. Maybe you could put your camera on a tripod and calculate distance d accordingly. No fog or low clouds allowed: On the picture we want to see these disturbing trees or the horizon (hopefully below your antenna center).

Best regards,
Ernst


Ernst Lobsiger
 

Robert,

as I said "(room and flat terrain assumed)". Maybe further back there is a point where you can aim to the center of your antenna with your inclinometer and make a small angle picture from there. But of course it's UK: No trespassing!

Regards,
Ernst


geojohnt@...
 

Hello Robert, Ernst and George,

I have just, rather belatedly, opened these discussion email's

I agree with much Ernst and George have said and will comment a little later on their suggestions.
The first thing I would say is that it looks to me that your dish is completely free of obstructions.
The tape/thick string LNB trick from top centre of dish to the LNB is very useful - and waiting for the 2 periods of co-linearity to see the exact shadowing - or not -of your dish.

The pole clamp may well be an issue - too low down. Even steel scaffolding poles twang in the wind, especially with a large dish mounted that high.

Forgive me if you have already done this and posted the image.
But have you used dish pointer?
It will give you a 'view from space' of your location, the pointing direct for selected satellite and show a line from your dish 'into space' so you can see any 'high' obstructions - trees/buildings ahead of you location.

https://www.dishpointer.com/

You may not wish to post your post code and house number on the group but if you email me personally I'll look it up and and see 'what might be in the way.'
This would be a good/essential start.

Best wishes,
John.



 





-----Original Message-----
From: Robert Moore <rsmoore@...>
To: MSG-1@groups.io <MSG-1@groups.io>
Sent: Sat, 2 Jul 2022 18:08
Subject: Re: [MSG-1] some progress

Ernst, This won’t help anyone very much, but this is the view from a little down my road, roughly now at the height of the dish, which is pointing over my right shoulder. All the installers have said that they get best SNR when lined up low in the notch between the trees.
Robert
 
 
From: MSG-1@groups.io <MSG-1@groups.io> On Behalf Of Ernst Lobsiger via groups.io
Sent: 02 July 2022 14:11
To: MSG-1@groups.io
Subject: Re: [MSG-1] some progress
 
On Sat, Jul 2, 2022 at 04:56 AM, Robert Moore wrote:
Unfortunately, Ernst I cannot do this. While I have a remote release for my camera, I do not have a means of getting the camera to the height of the dish.
Robert,

nobody asked you to climb on a ladder. All you must know or be able to measure is the distance h from the height of your eyes to the antenna clamps. Then you go a horizontal distande d = 1.8886 times h behind (room and flat terrain assumed) your antenna mast. The antenna pole must appear from the position of your camera at 162.4° azimuth. You can also use your compass and inclinometer to aim to the mast and dish center from the camera position. Maybe you could put your camera on a tripod and calculate distance d accordingly. No fog or low clouds allowed: On the picture we want to see these disturbing trees or the horizon (hopefully below your antenna center).

Best regards,
Ernst


geojohnt@...
 

George,

Yes the problem is, usually small portable 'sat meters' that many installers probably have do not decode VCM and so are unable to show SNR for those channels.
And Eutelsat E 10-A has few FTA TV channels. However there is an FTA horizontal TV channel - OK DVB-S but that doesn't matter, to line up on.

11.346 H, AFP HD Europe and on my 1 m dish I get -19.6 dBm power and SNR of 15 dB.

Also E 9-B is only 1 degree way and with my dish aligned on E 10-A with a quad LNB, I can watch TV from this satellite - Europe by Satellite, for example at SNR of 12.5 dB or the (useful) AFN test card on 11.804 V at SNR 13.8 dB.

My professional Inverto SatPal meter can't decode VCM so will not show EUMETCast SNR.
I align my dish on the above TV signal and then use TeamViewer of the SR1 Controller on my mobile to align for max SNR.

Regards,
John


-----Original Message-----
From: George Sz <szgydezign@...>
To: MSG-1@groups.io
Sent: Sat, 2 Jul 2022 10:20
Subject: Re: [MSG-1] some progress

That's a completely unobstructed view so there should be no issues here. That pole should be fastened more firmly indeed though. Make sure it's unable to rotate around its axis and try to add another fastener under the rain gutter. From this perspective, the dish could even be lowered, I think.

My theory is that you're not receiving the correct satellite (9°E is pretty close). My sat meter for instance has difficulty of locking onto Eumetsat's transponders due to the special modulation used, so another one should be used here for measurement. Maybe your tech guy did not have his meter set up correctly? There's not much TV to watch on 10°E so usually TV installer guys don't have this in their sat meters. Where are you located? I have a friend near London and maybe he could try. I can explain to him exactly what to do.