Help aiming a new C Band Dish

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robosat

SatelliteGuys Family
Original poster
Sep 25, 2012
66
3
North of Mexico
Hi Guys

I´ve been watching FTA KU Band channels for several years with my oval 3 feet dish mounted on a HH Diseq motor. Recently, I bought a 1.8m dish and a C/KU Band LNBF (BSC621) to enter into the C Band.
Altough I know a 1.8m Dish is too big for HH motors, I’ve read that a few FTA users do in fact move their 1.8m dishes with this kind of motor (at least for a small part of the whole arc). Anyway, the point is I cannot find any signal from KU or C Band with my new antenna and LNBF.
I’m brand new in C band issues, so I don’t know what I’m doing wrong.
I’ve aligned my old 3 feet dish (actually working well in AMC21) and my new antenna exactly in the same way, with help from a compass, a "+" form pipe (touching the edge of dish in its extremes), a Magnetic Level Angle Locator and simple visual references in my location.
When I moved my 3 foot dish from one place to another (just 2 meters away, mounted now in a fixed pole), I used these tools and visual references and I had no problem at all. Reception is great at new place for this small dish (as it was in its old place).
Now I installed the 1.8m dish exactly in the same place the 3 feet dish was, I aligned exactly as it was the little dish, and I cannot detect any signal ( Does it have to do with alignement that little dish is oval and the big one is not?)
I tried moving the LNBF closer and far (with and without the conical scalar ring) , rotating it , moving the dish from bottom to top (elevation), and panning the dish to west and east. All without ever receiving just a 10 percent of quality signal. Signal meters in the HDMicro always stay in 45 for Signal Strenght and 0 (cero) for Signal Quality. I’ve tried with KU Band and C Band (diferent coaxial connector in the LNBF), selecting the right LNBF type for AMC21 satellite in the MicroHD. I also tried with a Satellite Signal Meter, but I it keeps beeping even if I move the dish too much in the elevation and/or the azimuth; so It doesn’t help at all.
Forget the motor. The fact is I can’t get any signal from KU or C band just in the same AMC21 satellite I’v been watching for years with the 3 foot dish (KU band, of course).

Does anybody already know what I’m doing wrong or what is missing?
 
The dishes are probably different, the old Ku was off-set, the new C-band is direct feed. This means you elevation is going to be different. You will also need to be concerned with skew/declination. The old motor accounted for this automatically, the new mount does not, you need to set it. I suggest you try to set up on the satellite directly south of your location, then the dish can be aligned to "flat," for elevation, then, set declination by going from one end of the arc to the other and setting the east/west sats for best signal with the declination adjuster.
 
Is the 1.8m dish offset like your little dish, or is it prime feed (LNBF centered in front of the dish)?
You say you are adjusting the big dish exactly like the little one.
If the big dish is prime feed (LNB @ center), then it may be looking about 26 degrees too LOW! ;)

Did you set the LO frequency in your receiver to match the 621?
Probably 5150 for C band.
For Ku, the 621 comes either with a Standard (10750) Ku LNB, or a Universal LNB (you can check the frequencies).

I wouldn't recommend a dual-band LNBF on such a small dish.
Ku reception ... let's say I would expect it to be worse than your old dish.

You should be able to get something on C-band, so I would suggest you concentrate on that, only.

Im sure you will get many more helpful suggestions.
I have touched on only a few.
And please post a few pictures - that always helps.
 
Did you made the proper settings in the receiver's antenna settings? I have a 621 LNB if it is Standard the LNB has an internal 22KHz switch wish uses 22KHz tone to activate the KU Band.
Try aiming the BUD with a regular KU or C Band LNB, once you find quality then swap the LNBs and start fine tunning or tweaking for optimal quality signal, Hope this helps you Turbo
 
If you set your big dish at the same angle as your little dish then your elevation is off and you would need to point your big dish higher.

On the end of the BSC 621 ( the part that is pointing to the sky) you should have an arrow casted in it, this arrow should be pointed to the 9 o'clock position if you point your dish to the most southern satellite or better yet your true south. This would be your 0 degree position on skew.
Don't forget to turn your 22k on at the setup menu on your receiver.

When using an LNBF with a gain 60db or higher insert a 5 db attenuator between LNBF and the satellite finder ( el cheapo meter) to avoid full scale, this makes the meter more sensitive. Or you may try a 100 foot or longer coax between LNBF and your meter. Those meters do not do well with c band dishes.

I had used a BSC 621 2d LNBF for my 7 1/2 footer and my 10 footer before.
With an KU/C LNBF, you have to find a happy median between ku operation and c operation, with either band you may lose signal strength and possible channels. None of the 2 band will be optimized properly if you want KU and c reception at the same time on one big dish.
On 97 w for example I could only get 140 KU channels with my 7 1/2 foot c Dish and 180 KU channels with my 10 foot C dish.
With my turboHD dish that dishnetwork left behind I was able to get 240 KU channels.

I ended up to use a C band only LNBF on my motorized c dish and I am using a motorized geosat pro 36'' for my KU use.
After that I got more channels on C and KU bands.
 
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And please post a few pictures - that always helps.

That's what I was going to say. Specifically, please post a few pictures of the dish from different angles as well as a clear picture of the Antenna Setup screen on the microHD.

Also, do you mind telling us what type of dish you got and where you got it? (I'm hoping to be in the market sometime in 2013...)
 
One other thing.... Lyngsat does not show any C-Band at all on AMC 21. Am I missing something here?
 
Yes.....
AMC21 is Ku Only
Galaxy 14 is C Band
Both are located at 125 West

Correct.

Additionally and FYI, if anyone is concerned about it and desires better "tweaking" of the Ku band sat AMC 21, it is actually closer to 125.1°W
Not that it makes any HUGE difference in reception, but I found it helpful for my Ku band offset H-H motorized dish.
This does not pertain to the OP's subject, but since we were on this, I thought it should be noted.

RADAR
 
I knew somebody would tell me something important I was missing... Yes. Both dishes are not equal. The big one has LNBF centered in front of the dish; the other one is offset. I will try elevating some 21-26 degrees more the dish, and I will let you know, also including photos. I will do this when weather let me. Now it's raining and really cold.
 
Yes, it is important to realize the differences between a PRIME FOCUS and an OFFSET dish when it comes to alignment.
Looking forward to hearing your progress, once the rain clears out.

Back in my day, we wouldn't let a little rain deter us from setting up a FTA system.
Heck, I've set up a dish on a 3rd story home with an 18/12 pitch at 2 am in the middle of a raging blizzard at -40°F and 178 mph winds gusting to 240 mph with a broken leg and no coat or gloves! Just a tee shirt and shorts! Good thing I had a SuperBuddy meter!

Yeah right! :)

RADAR
 
Yes. I know AMC21 has no C Band channels. I just started with it because mi little dish was already pointing to that satellite, and tried to catch the same KU channels with the big dish. But now I will concentrated in C Band channels. Maybe in AMC18.
 
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