How to tell if a previously working satellite dish has now gone out of alignment

Forums › Freeview (DVB-T/DVB-S) › How to tell if a previously working satellite dish has now gone out of alignment

darreljnz

20 posts

Geek

Topic # 31660 25-Mar-2009 22:09

Hi all,

I have a satellite dish that has up until recently been giving me great Freeview DVB-S reception. All of a sudden I'm not getting any reception. The set top box is reporting "signal" of around 80% as usual but "quality" is now zero. I'm thinking this could be a symptom of my dish going out of alignment but I'm not sure. What possible causes are there for scenario where I get a high signal but zero quality?

I have repeated the test with a PC-based DVB-S tuner card with the same result.

Any help would be appreciated (even a basic guide to the difference between "signal" and "quality" would be handy).

Cheers,
Darrel

cyril7

6337 posts

Uber Geek
+1 received by user: 310

Trusted

Subscriber

Reply # 203402 26-Mar-2009 08:25

Hi, Signal strength is obviuously what it says, where as quality is a guage of the C/N (Carrier to Noise ratio) of the signal, this is how clean the signal is, and will only start to peak as you approach the last 5-10% of signal peak. Ultimately this is the parameter that you finally peak on, as signal strenght once past a certain point will flatten out.

Its hard to tell if the dish is out of alignment other than using a meter and peaking it up again. Dont forget that you are aiming for something the size of a Transit Van that 33,500km and your dish only has a 3deg wide beam width, so you may not even see the misalignment. It may even be the skew, which once again if you are not farmiliar with what you are looking for will never notice.

Unless you have a sat finder and are farmiliar with using it, it may be easier to get a installer in to check it out. PM me or as your in the Hutt give GZ member Brunzy a PM.

Cyril

darreljnz

20 posts

Geek

Reply # 203501 26-Mar-2009 13:39

cyril7: Hi, Signal strength is obviuously what it says, where as quality is a guage of the C/N (Carrier to Noise ratio) of the signal, this is how clean the signal is, and will only start to peak as you approach the last 5-10% of signal peak. Ultimately this is the parameter that you finally peak on, as signal strenght once past a certain point will flatten out.

Its hard to tell if the dish is out of alignment other than using a meter and peaking it up again. Dont forget that you are aiming for something the size of a Transit Van that 33,500km and your dish only has a 3deg wide beam width, so you may not even see the misalignment. It may even be the skew, which once again if you are not farmiliar with what you are looking for will never notice.

Unless you have a sat finder and are farmiliar with using it, it may be easier to get a installer in to check it out. PM me or as your in the Hutt give GZ member Brunzy a PM.

Cyril

Thanks for that, will do.