Bigger Dish, Worse Signal Quality

[Lazarus]

Chainsaw on standby ......

 

[davemurgtroyd]

Increasing the dish size has also made the dish more "tightly focussed" on the satellite arc. The Sky/Freesat satellites are a group of 3 satellites very close together and you can only perfectly align on one of those using a simple meter (such as in the receiver) - correct alignment is a compromise for the three and increasing dish size may well decrease readings for one particular channel with an increase in others. Normally your box is only measuing levels on one particular channel (usually the default EPG channel) and the only perfect way to align a dish is with a meter that shows the full spectrum from the satellites. Gain control may also have a bearing in this as well.

 

[Channel Hopper]

There will be no variation between signals between the various satellites on a Zone 2 dish. They normally move around within a 100km pattern which is imperceptible on much below a 3.8m reflector.

 

[KuchKuch]

My suspicions have been confirmed. I'm having severe picture distortions on some of the less known channels and its a dry day where I am. Never use to have a problem like this on a day like today before.

 

[Channel Hopper]

If the dish is on the same mounting bracket as the old one then you can more or less discount local elements such as trees affecting signal.

So , in order
Dish misalignment
Dish distortion/damage or possibly incorrectly assembled
LNB defective (it might have been mishandled during the changeover)
Connectors upstairs loose/faulty
Receiver has developed a fault.

With a Sky Q system there is no guarantee anything stays reliable for long.

 

[Lazarus]

Well the thing to consider is if the degradation is due to an imperfect dish installation, or the tree ........ or both. But the tree won't have changed much in a couple of days unless it's on steroids, so it must be the installation.

It's perhaps fortunate that the Sky Installer is due!

Edit: Sorry, didn't see CH's Post whilst typing this one.

 

[antrabe]

im afraid that spend money and after to buy a 1.8m dish the signal be worse than my offset 1.10m dish.
for sure c band will be better but ku band im afraid not to get the feeds of 10ºE and 7ºE

 

[KuchKuch]

I've taken a 30-40 second video clip as to how bad the quality is on my TV as I want to get some sort of compensation on the installation. Is there anything else people suggest I do to cover myself?

Hopefully this gets resolved tomorrow

 

[Lazarus]

Sounds like a good approach to protecting your interests.

Sadly, though, I suspect it will be to no avail.

But if the Sky bod tweaks it, you've not really suffered a loss, just a brief inconvenience.

 

[Channel Hopper]

You mentioned earlier that the upgrade was at 'no extra cost' so they will most likely tell you to get stuffed.

 

[KuchKuch]

You mentioned earlier that the upgrade was at 'no extra cost' so they will most likely tell you to get stuffed.

That was for the dish...not for the extra 2 feeds I got installed. Installation of the extra feeds and dish was done at the same time, so I may get something.

 

[Channel Hopper]

Two 'extra' feeds from a Sky Q dish ?

Something's not right

 

[KuchKuch]

Two 'extra' feeds from a Sky Q dish ?

Something's not right

Its installed with a Sky Q Hybrid LNB, which supports upto 6 feeds, so I can use Sky Q and a generic satellite receiver.

 

[Terryl]

How big of an increase in size from a zone 1 to a zone 2 dish??? And did he change the mount along with the dish, or use the old one?

If it's substantial size increase, and he didn't change the mount (don't know the differences between the two zone dishes) then the dish could be drooping due to the extra weight on the zone 1 mount. (if they are different mounts)

If he changed the mount then there could be a misalignment.

Usually for every 3 inches of diameter of dish size increase will add about 2 to 3 dB of signal increase to the LNB, this would not cause a reciver to be overloaded, as most have an AGC circuit to keep this from happening.

To test the dish to see if it has drooped you can use a broom sick or something else that can reach the bottom of the dish an give it a little push up, you would need someone to watch the "S" meter on the receiver to see if this helps.

Most of the time the mount and dish will droop due to gravity winning the pulling contest, a very small push up at the bottom of the dish will tell.

 

[Channel Hopper]

The LNB will - most likely - distorted the plastic feed clamp on the replacement dish, changing the 'angle of dangle'

You will not have got that with the older , beyond help zone 1 dish

 

[archive10]

There could be a hundred reasons for the installation to perform worse, but really, if the installer is worth his salt, he will come back and fix it if you tell him. Sky installers are no worse or better, it's a matter of getting someone who're honest about what they're doing.
Dont' let the Sky installer talk you into changing (and paying for) all sorts of things - get the original guy in to do a proper job!

 

[KuchKuch]

How big of an increase in size from a zone 1 to a zone 2 dish??? And did he change the mount along with the dish, or use the old one?

If it's substantial size increase, and he didn't change the mount (don't know the differences between the two zone dishes) then the dish could be drooping due to the extra weight on the zone 1 mount. (if they are different mounts)

If he changed the mount then there could be a misalignment.

Usually for every 3 inches of diameter of dish size increase will add about 2 to 3 dB of signal increase to the LNB, this would not cause a reciver to be overloaded, as most have an AGC circuit to keep this from happening.

To test the dish to see if it has drooped you can use a broom sick or something else that can reach the bottom of the dish an give it a little push up, you would need someone to watch the "S" meter on the receiver to see if this helps.

Most of the time the mount and dish will droop due to gravity winning the pulling contest, a very small push up at the bottom of the dish will tell.

Unfortunately i don't know what he changed with the dish (if anything) and I can't reach the dish without a ladder

There could be a hundred reasons for the installation to perform worse, but really, if the installer is worth his salt, he will come back and fix it if you tell him. Sky installers are no worse or better, it's a matter of getting someone who're honest about what they're doing.
Dont' let the Sky installer talk you into changing (and paying for) all sorts of things - get the original guy in to do a proper job!

I did try to contact him when I had my concerns and tried to contact him and left an urgent message for him to call me back once my fears were confirmed, but I haven't had any response so far.

I had booked the sky engineers to come tomorrow just as precaution in case something went wrong. I won't get charged as I'm a Sky customer.

 

[jeallen01]

The "local installer" in question sounds like a complete (insert your own expletive) "person"!

 

[Channel Hopper]

Dishpointer tells me I do have an obstacle and it is one of the trees Sky engineers are always concerned about.

Get out clause, right there.

Top up your bank account, they'll empty it before the week is out.

 

[KuchKuch]

Well the Sky engineer came and immediately noticed a weak signal on our main Sky Q box. He inspected the dish and noticed that the brackets were loose, which meant that the dish could move about slightly, and that it hadn't been aligned properly. He fixed all that and now my SNR varies between 88%-94%. Job well done I think.