Can any C-Band be rec'd on 90cm dish?

[bubba108]

alot of times those in-line amps mess up your signal even more.

Yeah, they bad.

 

[walrus1957]

Probably a crazy and ignorant question but I'll ask it anyways...Have a 36" dish with a Invacom QPH 031 LNBF for KU Band can I add a C-Band LNB and possibly pull in a few c-band channels - by way of my Mercury II Fortec receiver. Or would I need a larger dish?
Thanks.

Ok I have some experience here testing Cband on the smallest dishes possible so hopefully I can share some information to help you determine wether you want to pursue this avenue.

You will be disapointed using the 90cm dish as both a KU and Cband unless you go with a combo LNB like the BCS621, which incorporates both C and KU in one LNB. For max results using Cband it has to be mounted dead center on the dish. If you choose the BCS621 LNB, then you will miss your QPH-031 as the KU portion of the BCS621-1 or -2 leaves some to be desired (drops signal quality 10% at the least).

Your location isn't bad for most of the Cband broadcasts, however only the hottest transpnoders on the hottest birds you will recive. A 1 meter (100cm) Winegaurd dish is what I am currently using with a BCS621 and tested the GeosatPro C2 LNB (both are comparable for Cband). I attached the comercially produced conical scalar ring and can pick up channels from several sattelites. Of course my main concern where the DVB broadcasts from 91W 99W 121W 125W and 127W if I recall correctly. I did get channels from others such as 89W 72W 58W 55W and more. But the main channels I was concerned with were Fox News, Nat Geo on 91W, WHT on 99W, STO- Outdoors Sportsman and Sountrack on 121W, and RFDTV can't recal which sat that was on. Hopefully I quoted the correct satellites for each channel. The lowest quality using a Coolsat 5000 the 1 meter Wineguard, either of the LNBs I mentioned and the comercially produced scalar was around 80%, the strongest was around 98%. Which I beleive will hold up even in a mild rain storm.

Now if you want to boost the signal quality further than you can fabricate your own version of a conical scalar, I did and was able to bring in a lot more channels. But in doing so it so tightly focused the beam that you could no longer use it as a motorized system but better left as a fixed point dish.

All this been said I strongly recommend you purchase a second dish for Cband. If you can buy a 6 to 8 foot prime focus dish. If size and cost is an issue for you and you want to go offset dish for just a handfull of channels like I have, then yes you can get by with a 1 meter dish, a 1.2 meter you will be much happier with.

I have picked up a lot of back hauls using my 1 meter dish, and about 200 channels using my designed home made scalar. But then I had to re-tweak the dish elevation slightly each time I motored to a new sattelite as the beam focus was so tight.

So do not expect a lot from a mini BUD setup. As a hobby it is great. I have even been able to use a 76cm dish and pick up several Cband channels but a few dozen channels was the tops using the 76cm dish.

To me it sounds like you would like to enhance your system to pick up some reliable Cband broadcasts. Now you decide, I do not believe you will have any luck using the 90cm and mounting two LNBs to the dish arm. Purchasing an additional 1 meter dish for the price I don't think you will be happy with that either. A 1.2 meter dish then it might be worth the extra effort. A 6 foot or larger pime focus with a dish mover now your talking satisfaction, of course now the price goes up and so does the space in your yard required for the install.

Just my opinion and experience.

 

[Mr Tony]

Networks can be received on a 4 footer...as can most things on G16 C-Band

http://www.satelliteguys.us/fta-mpe...cal-scalar-ring-ws1247-120cm-offset-dish.html

 

[dfecarter]

Thanks Walrus1957 for your detailed input!
Intreging , will take it into consideration, although since the univ. lnb weakens the KU signal that would be detrimental to me, as KU band would constitute the majority of the programming. Will look up that lNB though. Now when you say the universal lnb for cband would have to be mounted dead center - do you mean closer in the my current set up?

 

[walrus1957]

Thanks Walrus1957 for your detailed input!
Intreging , will take it into consideration, although since the univ. lnb weakens the KU signal that would be detrimental to me, as KU band would constitute the majority of the programming. Will look up that lNB though. Now when you say the universal lnb for cband would have to be mounted dead center - do you mean closer in the my current set up?

I tried to fashion a dual holder for both my invacom QPH-031 and the BCS621 Cband lnb to operate from a single dish. However the Cband lnb has to be positioned where you have the invacom now (center in front of the dish). The large conical scalar required for the Cband portion positions the invacom to the side and becomes very dificult to set up correctly. Some members have posted photos where they cut a section out of the cband scalar to insert the KU lnb. Others have installed waveguide spliters and use different lnbs for each C and KU. All that becomes complicated but can be done. Then you really do not know how the whole setup will perform.

I only know what works for me, also know that using a 90 or 100cm dish you need all the signal you can get to make cband a possibility, that is why the cband lnb has to ocupy the center position in line with the lnb suport arm.

As to the KU portion of the BCS621 being weaker than what you can get with the QPH-031. That is true, and on some signals, especially a lot of feeds you may lose them. But for the bulk of the KU band you should be OK. I have noticed some of the weaker signals that I was getting at 70% using the qph-031 where the Coolsat threshold is roughly 63% on linear band cutout, the BCS621 dropped the quality about 10% and below the receivers ability to display video/audio. On strong signals that were coming in around 98% quality the drop was less noticable maybe 1 to 2%.

Another neat point about the invacom is you have two circular and two linear ports to run an additional receiver. The BCS621 has a single output but has a dielectric plate that can be installed for circular but I have no idea how it works, never had a need to test it.

Hope this helps.

 

[Anole]

The dielectric plate is only for circular C-band signals.
http://www.satelliteguys.us/c-band-...-c-band-circular-polarization.html#post922712
also: http://www.satelliteguys.us/c-band-...r-circular-polarity-question.html#post1801220
You'll find a few such birds pretty far to the east.
I'll let those who can see them make an argument for whether they are worth getting.