C Band Dish

[ozsatman]

Hello,

After not using my c band dish for about 2 years i thought i would try setting it up again. I can get the satellites from Asiasat 5 to Apstar 6, and nothing more east direction. Do i have to move the dish a certain way or have i just searched for the satellites and misssed them accidentally.

Any help would be appreciated.

Derek.

[mtv]

More info needed, Derek.

What you can receive will depend on your location, which you haven't mentioned.

Does your dish have an unobstructed view of the sky east to west?

What size is your dish?

Is the dish fixed or motorised?

If motorised, what satellites are memorised in your positioner and decoder?

[ozsatman]

mtv, I`m on the Gold Coast, Queensland, and the only satellite i have problem is Asiasat 5 with a tree in the distance, but i do get a signal. From Asiasat 7 round to Intelsat 18 the sky is clear.

My dish is a 2.3 metre with a actuator connected to it. I did reset the positioner and decooder in the settings for both.

[gordon_s1942]

Although you have some reception, it may not hurt to check you havent had unannounced borders move into the LNB as its very unusual for anything to remain unoccupied for 2 years on the Gold Coast I would have thought................

[mtv]

If your dish hasn't lost its alignment since it was last used, it should still be tracking the arc (Clarke Belt).

You need to load a transponder from each of the missing satellites into your decoder.

Lyngsat.com should have most, if not all transponder parameters for each satellite listed.

Then, move the dish manually with the controller (slowly) and point to each of the satellites whilst displaying the tuning screen for that satellite (with the transponder details already programed) until you get signal, then memorise the location on the positioner.

Performing a blind scan of that satellite should tune all transponders.

Repeat for the other sats.

If the dish/LNB has moved out of alignment since last used, you'll need to realign to get the tracking correct.

Keep in mind too that there have been several changes over the past couple of years.

Some program providers have moved transponders, changed satellites, use different encoding (eg MPEG4) or ceased altogether, so you may find things are not where they used to be 2 years ago.

[ozsatman]

Since i last used my dish the alignment is all out of line. So i`m sort of starting from scratch. If i can get satellites from Asiasat 5 to Apstart 6 does that mean i need to do a fine adjustment to the dish ?

I use my tv to see the signal of each satellite and started from Asiasat 5 and went to each other satellite until i got no signal at Telstar 18, Intelsat 19, Intelsat 8 and Intelsat 18.


EDITED: Do you think i`m on the satellite arc or just missing it ?

[ozsatman]

Today I had another go at my dish and I pushed and pullled on it and there was no signal change, so I adjusted the LNB slightly until i got the best signal i could on Asiaat 5.

I moved the dish with the motor very slowly from satellite to satellite and all TP`s are better, but I still can`t find Telstar 18, Intelsat 19, Intelsat 8 and Intelsat 18.

I had a look on Lyngsat and tried a few TP`s from there for each sat.

Which are the best TP`s to use for each satellite ? can someone tell me please.

[CONAXLE]

Telstsar 18 is weak on 2.3" I19 ,Int 8 and Int 18 shouldn't be hard to find on 2.3"...

[mtv]

Sounds like your dish is out of alignment... not tracking accurately.

[ozsatman]

Cheers for your help. So could it be the whole mount needs moving do you think ? or maybe the elevation. I will have another try tomorrow before the rain hits here.

[mtv]

Cheers for your help. So could it be the whole mount needs moving do you think ? or maybe the elevation. I will have another try tomorrow before the rain hits here.

It could be any number of things, or a combination.

As you've already discovered, the LNB skew was out a bit.

The dish elevation is set by the polar mount and the declination angle.

Once installed and aligned accurately, these adjustments rarely vary.

The most frequent thing I see is azimuth change... eg: a dish has moved horizontally/turned on the pole, so the alignment to true north alignment is lost.

Another thing I see a bit is the mounting pole has moved out of plumb, which will also prevent the dish from tracking the arc.

[tristen]

Should you need it, I have uploaded a copy of C-Band Dish Tutorial, previously posted by another member, to .

It appears to be a good explanation of how to align a motorised c-band dish.

[ozsatman]

tristen, ok cheers for that copy of C-Band Dish Tutorial. Typical as i wanna try get my dish setup properly, and it is going be heavy rain here the next few days.

[ozsatman]

Today i didn`t work, so i had another go at my dish. After mucking around with it for a while i ended up getting all the satellites, but some of the transponders have low/no signals.

I tried moving the LNB slightly both ways but couldn`t improve the signal. When the dish is facing true north what angle does the LNB need to be at ? Where the cable connects does it need to be around 7:00ish ?

[mtv]

When the dish is facing true north what angle does the LNB need to be at ? Where the cable connects does it need to be around 7:00ish ?

There is no exact answer as it depends on the individual location of the dish and the LNB used.

Typically for non-Optus sats, most LNB/F's that have an output connector on the side of the LNBF will be around the 6 o'clock position in the eastern states.

This is very approximate, as every LNB/F needs to be adjusted for skew and focal distance using a meter with a BER/MER measurement for accurate alignment.

Adjusting for the weakest desired transponder is recommended.

All transponders have variations in frequency, power output and beams, so don't expect them all to be the same.

Many may require much larger dishes to capture reliable signals.

[mtv]

briley,

Please start a new thread on your subject and not hijack someone elses thread on a different topic.

[briley]

sorry