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Using spectrum analyzer at a comm site.

3K views 7 replies 5 participants last post by  shortyfred 
#1 ·
I,m in Hawaii trying to use a spectrum analyzer (kusat) to locate Galaxy 19, but it seems as though there is so much RF that I cant see anything but noise. It has all kinds of RF there, it is on a comm/repeter site

Any suggestions?

Thanks for the help.
 
#2 ·
What type of antenna system are you trying to use? Do you have the SA connected to the dish LNB, or are you doing a 'horn' search? What are you trying to find?

There is a Christian TV Network on this bird at freq 12060-horz.

Here is the sight alignment information from your location. This should help.


Address: ewa beach hawaii
Latitude: 21.3169°
Longitude: -158.0132°

Satellite: 97W GALAXY 19 (G-19)
Elevation: 18.6°
Azimuth (true): 101.4°
Azimuth (magn.): 91.5°

Good Luck
 
#5 ·
If you are seeing what looks like all noise, then you are not receiving the desired signal. That can be because you are severly misaimed or there is no RF output from the LNB.

Are you sure the LNB is getting DC powering, either from the spec analyzer or from the satellite receiver? Can you arrange to connect your spec analyzer to a DBS DirecTV or DISH Network LNB downlead so that you can see what a robust RF spectrum looks like?
 
#7 ·
What happens if you use the same RF cable, but put a terminator on it (with the DC voltage turned off, of course), instead of connecting to the LNB?
You may be getting ingress right thru the cable.

If not, it's coming in at L-band, right thru the LNB. You might need a different LNB (something with a better filter on the input, or better shielding.
You might try a few torroids on the RF cable, to see if the L-band interference (from nearby cell and other transmitters) is getting fed back in to the LNB via the cable shield. You'd need to select the torroid's "mix" for L-Band frequencies, though. Call Tech Support at one of the Ferrite makers for their recommendations. (We had a similar problem with a UHF TV channel getting in "the back way" to a microwave receiver. Tech Support was very helpful in selecting the correct torroids. Then, we just ordered them from stock someplace, and got them in a day or two. Wish I could remember the company's name.)
 
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