Installing C Band - 180 CM Dish

[delsat]

Okay, I'm installing a C-band dish. It's the Sadoun 180 CM dish. Also I have a BSC621-2 C/Ku LNB which has diseqc switching 2x1.

Okay, I get a line quality of about 80 percent (which never changes) but I just have never received a signal yet.

You know, I understand the Diseqc switch only switches to two positions (1 & 2 or A & B) but I'm getting the line quality signal on all four positions.

I've been moving the dish (manually) trying to get some kind of signal but I never have.

You know, I'm experienced with smaller Ku-band dishes and I receive all the major sats around here, so I just fail to see how I am screwing it up now.

Also, I'm sliding the LNB up and down on the scaler ring to see if that helps and I'm not getting anything.

What do I need? Do I need to post some photos to show what I'm doing wrong, or is it possible that I got a bum LNB?

For instance, I should see some variance in the line quality, right? Also, it should not show (active-- 80 percent) on all 4 positions on my diseqc switch when it only has two pisitions.

I think I tried bypassing the diseqc switch, but I still didn't get a signal.

Okay, that's all on this one.

Thanks.

-Del

[elgemcdlf]

I would start by removing the jumper from the lnbf. I would run from straight Ku. I had better luck lining up a dish with this lnbf using Ku and then connected the C band after I located a sat. I believe you will not need to specify the port for DiSEqC but you might try putting it on port 2 for Ku. Secondly are we dealing with a stationary or steerable dish? A pic of your lnbf mounting would be nice. As to depth in the scalar ring my lnbf ended up being flush with the ring.

[BYX]

Originally Posted by delsat

Okay, I'm installing a C-band dish. It's the Sadoun 180 CM dish. Also I have a BSC621-2 C/Ku LNB which has diseqc switching 2x1.

Okay, I get a line quality of about 80 percent (which never changes) but I just have never received a signal yet.

You know, I understand the Diseqc switch only switches to two positions (1 & 2 or A & B) but I'm getting the line quality signal on all four positions.

I've been moving the dish (manually) trying to get some kind of signal but I never have.

You know, I'm experienced with smaller Ku-band dishes and I receive all the major sats around here, so I just fail to see how I am screwing it up now.

Also, I'm sliding the LNB up and down on the scaler ring to see if that helps and I'm not getting anything.

What do I need? Do I need to post some photos to show what I'm doing wrong, or is it possible that I got a bum LNB?

For instance, I should see some variance in the line quality, right? Also, it should not show (active-- 80 percent) on all 4 positions on my diseqc switch when it only has two pisitions.

I think I tried bypassing the diseqc switch, but I still didn't get a signal.

Okay, that's all on this one.

Thanks.

-Del

Del:
I'm not experienced as others but I went thru the experience of installing my own C band dish and this is what I can share with you.
The principles are pretty much the same of Ku.
Don't go crazy moving many things or everything at the same time.
You mentioned you already have Ku experience, therefore is needless to say that you should have your mast 100% plumb for starters.
You are talking about signal quality to be very high.
I believe you are talking about signal strenght but you have no signal quality at all, therefore you are not pointing to any satellite, otherwise you should be receiving at least something.
Do not work with your receiver just alone, make sure to have a signal meter to work with along with your receiver and a small TV next to the antenna.
The TV is your visual reference to see if you are receiving and to fine tune your quality.
Make sure the frequencies are correctly set on your receiver in reference to which side of the LNB you are using.
Focal distance is absolutely critical on these dishes. It is not like the Ku offset dishes.
From my own experience I learned that with 6' dish if you have the wrong focal distance you will not receive signals on Ku at all, you may see your signal meter literally "screaming" but nothing; but on the C band side with the wrong focal distance you will get at least the strongest transponders of the C band satellite you are aiming at.
Once you get a C band satellite lets say SATMEX5 that has true FTA channels, and lots of active transponders, try to adjust your focal distance and skew.
As for SKEW make sure that highest satellite or true south is where you are supposed to have 0° SKEW so when the antenna travels the SKEW is in the correct place.
You mention that your LNB has a built in diseqc.
Please verify if that is accurate. My LNB has a 22 KHz built in switch where 22KHz off is for C band and 22 KHz on is for Ku.

[delsat]

Okay, here is the photo. I hope this works. This is not the LNBF that I mentioned, but it is the same configuration. This new Orion LNBF just arrived that does only C-Band, so I thought it might be a little easier to work with (cheaper) or at least I would have a spare to verify that the one I have is working. (Cheaper than getting a new dish.)



In this second photo, the LNB I mentioned is sitting on the ground.

Although I got my first beeps (with both LNBs) they didn't appear to be related to any specific sats-- it looks like frequency bleeding from other sats, which sometimes happens with my ku dishes. I usually take this for a positive omen, however, that there is something in the vicinity, but I haven't been able to prove that.

I don't really have a mast for this dish and I don't really have permission to put up a permanent configuration.

However, I had the idea that I could just "lean" this dish temporarily against my brick wall and get approximately any angle that I want (as I do with my Ku-band dishes sometimes).

There is an issue, however, that this material is really flimsy and may bend if it touches the ground and distort the shape.

I guess this is a big issue -- even on C-band.

Well, take a look . . .

too warped?


Also, on the C/Ku band LNBF, I don't really have an indication of "up". I have a little arrow on the top, so maybe that's it.

On the C-Band (only) LNB, it is apparent that it is well marked (30/ | / 0/ | /30) so I guess that is not an issue. I guess it may give me a clue as to "up" on the other LNB as it looks quite similar. It also has graduated markings of 34/36/38/40/42/ (apparently related to the scaler ring), so is this supposed to be inches or cms from the center? I suppose this is useful -- if it works. Funny it's not marked on my first LNB.

Okay, that's all on this one. Thanks for all the good info.

Bye,

-d

[delsat]

Okay, these are the photos which are related to the test in my previous message.

-d

[BYX]

In all honesty and with all due respect, what you show in the picture is not the best scenario for any antenna.
You may get it to work but it is a very unstable and not meeting any basic standards.
I guess you are a victim of an association.
If they do not want you to install the antenna permanently, may I suggest you to install the antenna on one of those frames that you put blocks?
How about mounting a mast on a utility trailer that you can store when the association gets nosy?
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As for the antenna, on a regular installation where you have your polar mount on the back the plate with the brand should be your center, therefore your 0° skew.
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Based on my experience with my Ku system once you know where your south is, it is easy to figure out the arc and tweaking for a "perfect arc"
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In my case C band was not different even that I had some odds that I had to fight with, I am very happy with my C band dish. It is working beyond expectations and forecasts.
My antenna works beautiful even that there are opinions that 6' is marginal.
In my humble opinion it can't be marginal because everytime I get a satellite I receive it with no less than 70% quality and best of all with C band I have no rain fade.
On the Ku side I'm not that happy, I may have to tweak my LNB even more.