Cascade said:
Here's a link to a page I found where a fellow is doing that. Give it a look.
http://ourworld.compuserve.com/homepages/pjmarsh/cband.htm
120cm dish with C-Band performance - Now with HD!
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Here's a link to a page I found where a fellow is doing that. Give it a look.
http://ourworld.compuserve.com/homepages/pjmarsh/cband.htm
I read somewhere that the reason you can't get C Band on less than a 6 foot dish was because there wouldn't be enough separation between satellites.
Like trying to get 119 and 121 with a small dish. The width of the lnb being the limiting factor on a small dish. If you had a half width LNB at 119 then you could get 121 with a standard LNB, and receive both on an 18" dish. Have a big enough dish and 119 and 121 can be side by side.
So, I would think that rather then building a funnel into the C Band LNB on a 4" dish, you would need to build a dam which prevents the LNB from receiving any signal from the near by satellites.
Kind of like blinders on a horse. So that there is not any interferance from near by transponders on the same freq.
Would someone be up to making the C Band LNB window narrower? and seeing what happens?
Like trying to get 119 and 121 with a small dish. The width of the lnb being the limiting factor on a small dish. If you had a half width LNB at 119 then you could get 121 with a standard LNB, and receive both on an 18" dish. Have a big enough dish and 119 and 121 can be side by side.
So, I would think that rather then building a funnel into the C Band LNB on a 4" dish, you would need to build a dam which prevents the LNB from receiving any signal from the near by satellites.
Kind of like blinders on a horse. So that there is not any interferance from near by transponders on the same freq.
Would someone be up to making the C Band LNB window narrower? and seeing what happens?
jerryt said:
Very basically you'd choke the signal from getting into the LNB, radio waves are a specific length and won't effectively fit down a smaller opening.
As for a dish picking up 121 and 119 it uses 2 LNBs and a wider dish spread which is designed for 2 focal points that that spread.
The point of the scalar ring at this stage is to eliminate (as far as we can) TI, or terrestrial interferance which eminates from everything from the earth itself to radioactive birds.
The cone scalar only lets the LNB "see" the parabola of the dish.
As for not being able to receive C-Band on a 4ft dish, the results speak for themselves - it may not replace, or have the gain of a 10meter dish but it's working very well so far, PSB is even having success with his 40" (dish).
and I STILL can't get a anything with a 36 
I think kthis might be too small....havent tried AnikF1 yet...have a obstacle to over come
I think kthis might be too small....havent tried AnikF1 yet...have a obstacle to over come
Iceberg said:have a obstacle to over come
That wouldn't be the 30" dish you have sitting 22degrees infront of your 36" dish, would it?
What sats can you see with that dish? let me know and i will find some "hot" tp's for you. as i'm sitting here at home i can post back quickly.Iceberg said:and I STILL can't get a anything with a 36
I think kthis might be too small....havent tried AnikF1 yet...have a obstacle to over come
Cascade said:That wouldn't be the 30" dish you have sitting 22degrees infront of your 36" dish, would it?
for the one spot...yes
for the other (where the 36" already is) ..no
drhydro said:
The one 36” I should be able to see from about 101-west to 148
The problem is where I was going to put the one 36”, I can see IA6 & G3…after that the dishes on the roof block it (this one is on the deck railing which shoots over the roof). The deck is north of the house, so when I aim the dishes on the deck, I have to shoot over the ones on the roof.
The other 36”, which is at G10 right now, I tried to get Outdoor Net yesterday and nothing : (
So if I move it, I should be able to see probably 101 west…anything east and my 24” motorized & dish500 will block it.
I might see if I can get the AnikF1 feeds, but I think part of it is the C-Band LNB. I’m trying to figure out how to get it to find the focal point. I think it is off.
I think your problem (with C-band) is the focal height, my LNBF is around 50mm too high, and as such the elevation to the sweet spot is WAY off, so do not trust your elevation setting. I would aim for the Anik F1 channels as they seem to be the strongest for us in this area......... drop the LNBF to me if you want me to test it out.
Offset C Band LNBF
What is an C Band LNBF for an offset dish?
http://eyeinthesky.net/cgi-bin/show_full_desc.cgi
Is this BS or something which is required?
What is an C Band LNBF for an offset dish?
http://eyeinthesky.net/cgi-bin/show_full_desc.cgi
Is this BS or something which is required?
jerryt
It'll have a feedhorn compatible with the F/D ratio (most likely .7) that will allow complete illumination of the dish. Most prime focus dishes are deep with F/D ratios of around .375. The scaler type of feedhorn rejects adjacent interference while allowing complete illumination of the reflective surface.
It'll have a feedhorn compatible with the F/D ratio (most likely .7) that will allow complete illumination of the dish. Most prime focus dishes are deep with F/D ratios of around .375. The scaler type of feedhorn rejects adjacent interference while allowing complete illumination of the reflective surface.
jerryt said:
That url won't work, though I know exactly what you mean off that site.
To be honest, me and another forum member think that is a normal c-band lnbf with a 50 cent dialectric wedge, so they can charge an extra $20.
We've also looked humorously at the 4' "DBS only" $200 dish there...
We're guessing it's a badly made parabola so only high-powered DBS signals will work decently on it
Don't get me wrong, this is where I'm ordering my dish from.
It's just funny
Just received my offset C-Band LNBF and it has the cone shape ring - this is the real deal guy's. It comes with a nice heavy duty mounting bracket that fits the throat that will attach to your LNB arm. I have yet to attach it to the mounting bracket because I will need to change support arms and I wanted to get it on the dish asap. I have it tye wrapped and found it likes to be as far towards the dish as possible with the scalar set at the .42 mark. I am still on Anik F1 and have noticed perhaps a couple of % difference in Quality on some channels. One H-pol channel which I could not get before, I can now even though the quality is lower that the majority of the other xponders at 68-69%. Even though the ad on the EITS website said that there was a dielectric slab inside, mine did not have this. The picture shown on the website of course did not show the cone ring either.
The brand is Astrotel and it case you're curious the model is - PM-9/ C-V/H GOLD.
The brand is Astrotel and it case you're curious the model is - PM-9/ C-V/H GOLD.
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Nice!
Get those pics up
Rayydio, if you can get all angles, measurements etc you'd make a lot of people happy.
(If you leave the LNB on your dish I'll be round at 3AM with the wrench )
Get those pics up
Rayydio, if you can get all angles, measurements etc you'd make a lot of people happy.
(If you leave the LNB on your dish I'll be round at 3AM with the wrench
)rayydio
If your feeling like living dangerously, machine the end out of the ASC421 waveguide and attach your ku lnb to the open end with it's weather lense removed. You'll have a dual band setup. That's how it's done. Once the signal is inside the waveguide it can be processed by both lnb's. The higher frequency of the ku signal will be directed to the ku antennae probes. There would be some signal loss however because of the abrupt transition into the ku section of the waveguide..
If your feeling like living dangerously, machine the end out of the ASC421 waveguide and attach your ku lnb to the open end with it's weather lense removed. You'll have a dual band setup. That's how it's done. Once the signal is inside the waveguide it can be processed by both lnb's. The higher frequency of the ku signal will be directed to the ku antennae probes. There would be some signal loss however because of the abrupt transition into the ku section of the waveguide..
related to this thread.. I see that CTV is ITC on Anik F1, but is 8PSK.. is there anything commercially available that can decode this? My sister wants to watch Canadian Idol, and It would be easy to put a 1.2m Mini-bud on her roof to get it, other than her coming over to my place every week to watch it on my *C system
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