Can using two 1.2 c band dish with one lnb increase C/N by using waveguide fitting
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In theory, yes. If the hardware is identical, everything is installed perfectly with exact alignment, focal distance, skew setting, waveguide length - so to have exact phase and timings.
In reality, no. The hardware and components would need to be commercial quality with exceptional specifications, compliance and build. The slightest variation will induce phase and timing issues. Most would only be able to pull this off on a fixed dish system as high resolution tracking and skew would be required.
In reality, no. The hardware and components would need to be commercial quality with exceptional specifications, compliance and build. The slightest variation will induce phase and timing issues. Most would only be able to pull this off on a fixed dish system as high resolution tracking and skew would be required.
Welcome to the forum FTA Hunter!!!
If you have deep pockets to get something machined to exact precision, to pull this off, I want to see tons of pics and a post by post account of the how it goes.
Zero room for error on something like this.
If you have deep pockets to get something machined to exact precision, to pull this off, I want to see tons of pics and a post by post account of the how it goes.
Zero room for error on something like this.
A Lot LESS $$ and a lot less headaches, IMHO, if you just put up a bigger dish.
If you can't put a big prime focus dish up at your location, there's the possibility of having it remotely located. A microHD with a SlingBox - control it over the internet. (think you have to program it locally)
Use the 1.2 for Ku - they work great there.
Welcome to the site FTA Hunter.
EDIT: I ran some 'numbers' for my Humble Opinion:
at 4Ghz
A 1.2m offset will have around 31.02 dBi gain
Doubling the dishes will result, "ideally" in 3db gain.
but usually nearer 2.5db with good construction.
So 31.02 + 2.5 = +33.52db
A 1.8m (6') will be approx +34.54db
So a 6ft would probably outperform the "mated" 1.2's AND requires less space.
And no exotic engineering.
JMHO
If you can't put a big prime focus dish up at your location, there's the possibility of having it remotely located. A microHD with a SlingBox - control it over the internet. (think you have to program it locally)
Use the 1.2 for Ku - they work great there.
Welcome to the site FTA Hunter.
EDIT: I ran some 'numbers' for my Humble Opinion:
at 4Ghz
A 1.2m offset will have around 31.02 dBi gain
Doubling the dishes will result, "ideally" in 3db gain.
but usually nearer 2.5db with good construction.
So 31.02 + 2.5 = +33.52db
A 1.8m (6') will be approx +34.54db
So a 6ft would probably outperform the "mated" 1.2's AND requires less space.
And no exotic engineering.
JMHO
ahhh, ok what about if i use square tubing alumni as waveguide. I did some testing with c band lnb where i placed the scaler ring at 40mm in a 1 meter alumni tubing rhe other end was i placed a 15k LNB. there was no drop of signal.
Hi FTA. Ahhh but that was on a SINGLE dish & lnb. The answer for your question on a dual dish system already given above!
array's of antenna's have been used for years, they add a significant amount of complexity though.
http://www.vla.nrao.edu/
http://www.directivesystems.com/DSFOATV-25.htm
the higher the frequency the tighter the tolerances. The higher order the modulation, ie QPSK, 8/16/32 PSK etc makes the tolerances even tighter.
So can it be done? yup, is it worth it? no. Reasons stated above.
UDL
http://www.vla.nrao.edu/
http://www.directivesystems.com/DSFOATV-25.htm
the higher the frequency the tighter the tolerances. The higher order the modulation, ie QPSK, 8/16/32 PSK etc makes the tolerances even tighter.
So can it be done? yup, is it worth it? no. Reasons stated above.
UDL
You can buy all sorts of Waveguides on Ebay. Just search using the term: waveguide
Maybe you can find something useful.
Maybe you can find something useful.
Take your time to get the phasing right. Do you have something to view the IQ plot with? It should help
UDL
UDL
Welcome to SatGuys, Fta hunter!
Phasing would be your biggest problem, I'd think.
Square aluminum stock I would think would be all right but maybe stainless might be a better choice, if you have a long waveguide of aluminum and it condenses moisture inside and then corrodes inside, your signal may start to go south on you. I never made waveguides for low power stuff like satellite TV, so I'm really not sure. I'm sure some other people on here know and will respond. How long of waveguides do you think you'll need?
Do you have a TIG welder that you could use to weld flanges onto the tubing with?
Phasing would be your biggest problem, I'd think.
Square aluminum stock I would think would be all right but maybe stainless might be a better choice, if you have a long waveguide of aluminum and it condenses moisture inside and then corrodes inside, your signal may start to go south on you. I never made waveguides for low power stuff like satellite TV, so I'm really not sure. I'm sure some other people on here know and will respond. How long of waveguides do you think you'll need?
Do you have a TIG welder that you could use to weld flanges onto the tubing with?
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