Focal point of GEOSATpro 90cm?

[Kermee]

Hi All,

I finally got a chance to setup a GEOSATpro 90cm I purchased about a year ago with a GEOSATpro SL1 and I'm aiming at Galaxy 19 (97W). Currently using a Sonicview SV-8000HD that was given to me by a friend who no longer uses it.

I got the LNBF skewed about -21 degrees and I can get almost all the TP's (Q 38-51) except for one, which is 11966H. I can barely get a Q of 25-29 on it and I get no video and broken-up audio while attempting to tune into channels located on the TP (e.g. The Word Network).

I have a feeling that from my location, 11966H is *the* weakest TP to tune into and I've tried my best to lock it in with a better Q and just haven't had much luck. Now I'm starting to wonder:

#1. Is my LNBF bad in general since it seems all my Q's are relatively low (Highest Q on a TP off Galaxy 19 is 51.)
#2. Is the LNBF arm munged up during shipment so that my LNB isn't at the focal point?

I've changed out RG6 and I was using a short run anyway for pointing. The dish doesn't 'appear' to be warped and I haven't done the 'string test' yet which I will later this week. The mounting-mast *is* plumb.

... So this leads me to believe that possibly the LNBF/SL1 isn't at the correct focal point of the dish. And I realize this is an 'off-set' dish, but is there a way I can figure out, other than sliding the LNBF back-and-forth, what the proper distance is for the LNBF to be from the dish?

Thanks in advance!

Cheers,
Kermee

 

[Mikey11]

the SV8000 is known to show lower than "normal" quality numbers....in my experience with that receiver your quality numbers seem very good for your dish size....your lnb is not bad if your getting other TPs both H and V....that receiver will normally show a good "unbroken" picture all the way down to 5 Q or sometimes even less....

 

[Kermee]

the SV8000 is known to show lower than "normal" quality numbers....in my experience with that receiver your quality numbers seem very good for your dish size....your lnb is not bad if your getting other TPs both H and V....that receiver will normally show a good "unbroken" picture all the way down to 5 Q or sometimes even less....

Hi Mikey11,

*Nod* -- Thanks for the info. I gathered that the 'Q' numbers reported were definitely a bit lower vs. other models/brands for the same 'Q' from researching and searching here on the forum before I signed up to post.

When I was tweaking the dish, I noticed that if the Q number went below 30 (for Galaxy 19), the A/V would start breaking up. Once around Q28, I'd lose video completely and the audio was breaking up. So for 11966H, it hovers around Q28-Q29 with broken audio and no video for any of the channels on that TP.

Maybe I have an incorrect setting for the TP? (11966H, 22000, FEC at 3/4)... I'm sure if I had the incorrect settings, I wouldn't be getting any Q at all.

Cheers,
Kermee

 

[SatelliteAV]

None of the transponders on Galaxy19 should provide that low of signal threshold.

Transponders 11842 and 11966 can appear to be slightly off axis due to slight adjacent satellite interference, so be careful not to peak the dish aiming using only one or two transponders. The trick to good Galaxy 19 reception is to maximize Signal Quality readings, but then average between several transponders.

Performing a string test on any dish is a critical step in dish assembly. An 1/8th or 1/4" gap in the strings will severely attenuate satellite signals, yet this amount of warping will not be visible to the eye. Easily corrected, but most likely could be the cause.

Setting the correct FD will slightly affect the Signal Quality and you may notice a 5% variance when sliding the LNBF towards or away from the reflector. It will not greatly affect the signal.

Most likely not a defective LNBF as these are factory screened and verified in a special screening process. We experience less than 1/10th of one percent failure of the SL1 within 3 years of installation. I would look for other causes such as a warped or bent dish, line of sight issues, coax cables or connections, LNBF rotation (skew) settings.

Due to the design of the shipping box, it is highly unlikely that the lower LNBF support arm or the side support arms would be damaged. Was there severe damage to the shipping box?

Look for other causes for this low signal.

 

[rv1pop]

My vote for that problem is WARP.
The second vote getter for that problem is Warp.
And second runner up is warp.

Do a string test, correct the warp and watch the signal go up. Seattle is not that far from Lynnwood, SeaTac or Kirkland. I had the same symptoms all three locations while on the road with the motor home. I corrected the warp and signal came up.

Adjacent transponder interference has not been a problem FOR ME in that area. The side braces are a great help but the banging in the motor home is too much for that dish. Dish is now in Lynnwood and added the "new" transponder without adjustment.
POP

PS.If you get an H and a V transponder, the bullet LNBF is working!

 

[Tron]

My vote is for a warped dish as well. If you lay the dish face down on a totally flat surface and any part of it doesn't lay flat, that points to this sort of signal quality problem. It's usually easy to "pop" these dishes back into shape by holding the dish in front of you with both hands and apply pressure against the warp from the edges. You'll hear a "pop", and it will be back in its proper shape.

 

[Kermee]

Thanks, everyone, for the suggestions!

When I was assembling the dish, I should of checked the dish for warping and the fact that many people pointed out that it may not be 'visibly' detectable, I have a feeling I missed it. I'll check it this week and update with what I find.

Thanks again!

Cheers,
Kermee

 

[rv1pop]

Do the string test now. It only takes removing 4 bolts off the mount and two bolts on the braces to remove the reflector to unwarp it. I left 4 strings taped to the dish, for several months while I figured out that 65 MPH winds bouncing off the building wall were causing most of the problems I was having. Left the dish mounted on a roof in So. Everett and no more problems.

One string, top to bottom; one side to side near the middle; two diagonally splitting the distances between the others is more than enough to see the problem.

edit to add: I never could find a flat enough surface to convince me that the dish was warped. The strings did it each time and leaving them taped to the dish gave a very quick daily check. Strings touched no problem. An eighth inch gap, problem! A Quarter inch gap, many problems, usually lost 2/3 of the signals.

 

[Kermee]

Just an update...

I finally got around to doing the 'string test' and the dish passed with flying colors. -- As a last resort, I decided to 'slide' the LNBF towards the dish and all of a sudden, the Q jumped by about 20 points and it was locked solidly on 11966H. Guess I should of done that first... *Shrug*... But moving it up about 2cm made all the difference. Rest of the TPs on Galaxy 19 are coming in around Q60+ now too...

Thanks again to everyone for their help!

Cheers,
Kermee