Cband but not the Ku-band
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I have been having some problems with my new c set up as you are now.The solution for me was my dish elevation was off!good enough for c but not for ku and since the KU band is a narrower band i found that locking in on the ku first also gave me a lock on the c!not the other way around.
If you could tell us the dish/LNBF combination you are using (pictures would help) someone on the forum might have the same thing and some suggestions.
Because the frequency is higher for KU band, the accuracy of the dish's "parabola" shape is much more critical. It is not unusual for the KU signal to be low on a C band dish. I have tried to adjust C band dishes to a weak KU signal where it would not hold the signal just because of the dishes movement in the wind, replaced with a 90CM and no problem.
Bob
BTW
Because the frequency is higher for KU band, the accuracy of the dish's "parabola" shape is much more critical. It is not unusual for the KU signal to be low on a C band dish. I have tried to adjust C band dishes to a weak KU signal where it would not hold the signal just because of the dishes movement in the wind, replaced with a 90CM and no problem.
Bob
BTW
I am trying to get Galaxy 19 and the LNB is a "Universal C/Ku Band LNB 13k (Sat6212-2/741u). This is the specs for the LNB:
C Band
Input 3.4~4.2 GHz
Output 950~1750 MHz
LO 5150 MHz
Gain 65 dB
Ku Band
Input 10.7~12.75 GHz
Output 950~1950 MHz Low band
1100~2150 MHz High band
LO 9.75 GHz Low band
10.6 GHz High band
Noise 0.3 dB
C Band
Input 3.4~4.2 GHz
Output 950~1750 MHz
LO 5150 MHz
Gain 65 dB
Ku Band
Input 10.7~12.75 GHz
Output 950~1950 MHz Low band
1100~2150 MHz High band
LO 9.75 GHz Low band
10.6 GHz High band
Noise 0.3 dB
The hole size could be an issue if the holes were real big, but I haven't seen a dish made in the past 25 years which had mesh that was too big for Ku. I agree with wescopc that if the dish can't do Ku, it's probably due to shape not mesh size. My first dish couldn't do Ku due to shape. I tried putting in a fine mesh screen, thinking the hole size was too big, but it didn't help at all. My current BUD used to work quite well on Ku, but over the years it has warped and become dented and no longer works on Ku.
However there is another possibility, and that is having the feed at the proper focal distance. I've found that if the feed isn't at the right distance, that C-band will still work, but Ku will have a signal pattern that is more like a donut, where it has a minimum at the center aim position, and actually has focuses in a circular pattern around the point where C-band is aimed. I'd get Ku signals to lock at two different points, either side of where C band was peaked. When I adjusted the focal distance to the proper point, then C and Ku focused at the same point.
Since noticing that, I have first peaked my dish on C-band, then adjust the focal distance until I get reception on Ku, then fine tune on Ku.
Also, since you have a universal LNBF, are you sure that you have the proper configuration in your setup? Ie if you don't have it set up with the proper switch settings, LNBF type, LO freqs, then you might not get anything.
However there is another possibility, and that is having the feed at the proper focal distance. I've found that if the feed isn't at the right distance, that C-band will still work, but Ku will have a signal pattern that is more like a donut, where it has a minimum at the center aim position, and actually has focuses in a circular pattern around the point where C-band is aimed. I'd get Ku signals to lock at two different points, either side of where C band was peaked. When I adjusted the focal distance to the proper point, then C and Ku focused at the same point.
Since noticing that, I have first peaked my dish on C-band, then adjust the focal distance until I get reception on Ku, then fine tune on Ku.
Also, since you have a universal LNBF, are you sure that you have the proper configuration in your setup? Ie if you don't have it set up with the proper switch settings, LNBF type, LO freqs, then you might not get anything.
Let's have some specs on your dish... and pictures. 
We know what a 741/u is.
And to amplify what BJ said above, if the LNBF is not perfectly centered on the dish, the Ku and C will focus at different places, giving you no apparent Ku reception.
Ku's far more touchy.
We know what a 741/u is.
And to amplify what BJ said above, if the LNBF is not perfectly centered on the dish, the Ku and C will focus at different places, giving you no apparent Ku reception.
Ku's far more touchy.
The focal length, ratio and skew are important. Also you may need to bump the dish either east or west as ku might not be the same quality where c is located.
If you read through my old posts, I went through this trying to tune a BUD with a BSC621-2. It might be helpful. But definitely look at FL, F/D, Skew and azimuth as it may differ from c.
If you read through my old posts, I went through this trying to tune a BUD with a BSC621-2. It might be helpful. But definitely look at FL, F/D, Skew and azimuth as it may differ from c.
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