satav c/ku lnbf setup with gbox?

[outbackjack]

i searched the threads in cband but i couldnt find anything. i got a new geosat c/ku from satav. it shipped extremely fast and seems to be extremely well built. the deal and packaging was awesome!! it is a heavier build than the other c/ku i have and the scaler is bigger my question is when i connect it to the 6 footer is the focal distance the same as my cband lnb? i figured the skew is the same because it is run by an actuator. i want to make sure i dont loose cband strength but maintain a viewable ku (97w). the only reason i'm using combined c/ku is because it is so darn cold i could not spend the time outside rewiring my ku dish (i swapped cables to my 6 footer) and the 6 footer with the gbox. i was hoping to get the best of both worlds until spring with minimal outdoor time. Maine is tuff on the skin of this old man!!!

 

[outbackjack]

Brent, Ice, Doug, Satav, anole or anyone else have professional advice on this? just want to know focal depth with this compared to a cband lnb.....is it the same or does it need to come closer for ku?

 

[crackt]

my rule of thumb is to set the feed in the scalar using the scale on the feed throat. if there is no scale then i use the info here : Welcome To Chaparral Communications
ive never had luck with c/ku lnbs. they seem to be on the extremely touchy side and i have to many things going on to invest that much time in tweaking them. you will find that there will probably be a trade off between c and ku performance and some people add a 1/2 inch spacer between the c an ku portions of the lnbf. this is only my opinion based on testing the ck1 and dmx741u versions.

crackt out,.

 

[SatelliteAV]

There is no right answer. The placement of the CK1 for FD optimization will vary depending on the FD and sweet spot on your dish. The FD setting on the CK1 will be more critical with KU-band than the C-band. Try placing the FD at a similar setting as a C-band feed horn then make slight FD adjustments while viewing the Signal Quality reading on a KU frequency. The CK1 has a scale stamped in the feed horn. Haven't heard of the 1/2 inch spacer block modification used on the CK1 model. GEOSATpro models are from a different manufacturer than the WSI and DMS models and have major design variances.

 

[Anole]

yes

.. i figured the skew is the same because it is run by an actuator..

How to set the starting skew of the LNBF with the dish at your true south satellite:
http://www.satelliteguys.us/c-band-...lp-me-think-through-geosat-5.html#post1281374

 

[outbackjack]

thanks for the info uys, thats why i love this forum. things that i cant make sense of....you guys do i just wanted to make sure the f/d didnt have to go in way further than the c. i will give ot a try at what i have my lnbf at now. one other thing i noticed while running sichbo or satdvb is when it goes to scan ku (i only have a c lnb on there now) it is threw the roof varies 90-100 percent. is this just a software flaw or is it really picking ku up on the c but not able to transfer the signal because the new c/ku one isnt on there yet?

 

[crackt]

some more points to consider when installing an lnbf or feed horn on a prime focus antenna... the amount of feed protruding thru the scalar determines how much of the dish the feed will collect signal from. if the feed is not set to the scalar properly the dish will see less of the dish than it should and collect less signal than possible OR the feed will see past the edge of the dish and collect terrestrial interference. for this reason i set the feed and scalar for the f/d ratio of the dish and then install the assembly on the dish as a unit paying attention to the focal distance and feed centering. there is a small sweet spot that really exites the lnb(s). if you install the lnbf into a scalar already mounted to the dish and the focal distance is not correct... remember this post when your wondering why your signal quality is not quite where you thought it would be. it will probly take some tweaking and beverages to get it dialed in. patience is definately required.

crackt out,.

 

[outbackjack]

well crackt i bought the beer and am ready for some fun tomorrow. it is supposed to be a balmy 18 but might get near 30 i am going to try to get that beeper update to the coolsat tonight so i can leave the window cracked to hear if i hit the signal. i just have to find the old pc cable to connect it. still messing with the sichbo and am getting almost passed the learning curve