97W and 125W using 2 dishes

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Multi feed LNB holder

Does anyone use a multi-feed LNB holder to get multiple satellites on a single dish? How feasible would it be to use such a thing on a 36" dish to get 97W and 125W? How does this method compare to using 2 dishes?
 
central1ny said:
Does anyone use a multi-feed LNB holder to get multiple satellites on a single dish? How feasible would it be to use such a thing on a 36" dish to get 97W and 125W? How does this method compare to using 2 dishes?
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It's not possible to use a single 36" dish to get satellites that far apart. You might be able to do it with an elliptical dish (like the larger Primestar dish), but even that is iffy. Now, IF they were high-powered DBS sats you'd have a chance for sure (still with the elliptical dish). Doing a dual setup like this has a lot of variables, and is worse the farther apart the sats are.
 
Screenshot_1.pngThe only solution that would work for this is a toroidial dish. Rather espensive but it is advertised to cover 40 degrees of the arc. This dish is popular in Europe. You can get more information here> http://www.wavefrontier.us/
 
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Much simpler (IMHO) to set up a second dish. Could be done, i would suppose, if a Large dish were employed. But setting up a second .8 to 1m would be way quicker, and cheaper. Dish/LNBF and a switch is all that's required.
Think a "multi-feed LNB holder" will get you satellites from 6 to somewhere around 10 or so degrees from the "Boresighted*" central LNBF. *at the dishes true focal point. Maybe more depending on the dish size.
A dish has only one true focal point. It's a simple 'lens' to concentrate signals from a distance to one point close to the dish. LNBF's offset from the focal point don't get the advantage of the true focal point where all the focused signal will enter the feed throat. There's a lot of the signal that will not be 'focused' into an offset feed.
The only solution is to employ a bigger dish, to hopefully get enough signal to the feed, with offset feeds, or separate dishes.
Employing an elliptical, could conceivably work. But each, 97 & 125,(Again IMHO) would have to be 'offset'. The dish would have to be 'boresighted' on a satellite midway between 97 & 125. Like 111, Then each LNBF (for 97 and 125) would be offset by 14°. Another thing to consider is the 'skew' of the arc. The dish should be skewed to the skew of the 111 satellite. Not just the feeds to the satellites being attempted.
 
I agree. Two 90cm elipticals could be had for less money, or a motorized 1 meter. Those toroidial dishes have been around for awhile but still haven't gained popularity here for that reason. Besides 125w is a problem child for many users anyway.
 
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Agree with Jorgek that the larger dish should be on 125w and the smaller for 97w. If you want to go with a single dish, it is possible.

Boresight the dish for 113w and offset two LNBFs. 12 degree offset for 125w and 15 degree offset for 97w. A 15 degree offset from center is very obtainable on a 90cm standard offset or larger dish.
 
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Good evening.
Reception on one Dish some companions at us in Europe very much practises. At me it is established Dish on 1,2 m Offset so on it perfectly go 8 satellite. And from focus 19,2e to 36? - 17 degrees and a signal excellent on 36?. On Dish offset 0,9 m 4,8e/F/-19,2e - 14 degrees.
The only solution is to employ a bigger dish, to hopefully get enough signal to the feed, with offset feeds, or separate dishes.
Employing an elliptical, could conceivably work. But each, 97 & 125,(Again IMHO) would have to be 'offset'. The dish would have to be 'boresighted' on a satellite midway between 97 & 125. Like 111, Then each LNBF (for 97 and 125) would be offset by 14°. Another thing to consider is the 'skew' of the arc. The dish should be skewed to the skew of the 111 satellite. Not just the feeds to the satellites being attempted.
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-FaT- all is correct. I would advise eksperement - on Dish 1,2 m.? focus to put and adjust on 113,0w, well and then along the edges 97 and 125w. Signal on these the companion excellent.
1.2м-7-36е.jpg0.9м-4w-19.2е.jpgмульт-36-60.jpg97w-KU.jpg
http://www.satstar.net/satellites/sm6.html125w-C-.jpg
 
I'd experiment also. First by aiming the dish directly at 125W and recording my Q readings. Then aim it at 113 or 111, then try to get 125 with an offset LNBF. The cost of it is only a bracket, switch, and LNBF.
Just don't know if a 90cm dish is enough as performance will 'fall off' with the offset feeds. So the performance is comparable to what? A 70cm? I get squat, "0", on 125w with a 70cm aimed at it. That is what concerns me with the espectation of success. But the 84e works very well 'boresighted'**. The maps above show that 125W is some ~8db weaker than 97W. That's quite a 'bit' I feel. The only solution, I see, is at least a 1.2 meter with offset lnbf's. If determined to go that 'route'. But 1.2m dishes are $$$(with shipping)***.
One can try the offset route, and see if it will work. Part of the hobby I'd say. If not there are alternatives.
Putting up a second 90cm dish*, or adding a motor, are 'cost effective' solutions. IMHO
Think everyone here uses either a dedicated or motorized dish, 90cm or larger, for 125W as it's all DVB-S2 also. (Needs more signal to lock on to)
* or the 90cm aimed at 125 and a 70-75cm aimed at 97W.
**Montana is a bit low, 50 -60 Q, and breaks up a bit. The others are Q70+
*** Unless you locate one that's available for little or nothing locally.
All in all, 'go for it' with an offset lnbf, I'm just over thinking 'out loud' my thoughts, and 'go from there'.

On another topic: God man, aren't you worried about starting fires with those eirp values?
http://www.satstar.net/beams/astra4a_eurb.html http://www.satstar.net/beams/amos3_eurh.html
Average ~10db stronger than anything this side of the pond. That's big time strong. just put a lnbf on a funnel??
The DBS satellites spot beams may be that 'hot' here, but not FTA, and they can be had with a 50cm dish.
 
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merged threads together since its the same OP and basically asking which is better..one dish or two separate
 
waylew said:
In fact when I first started picking tv signals from space,20? years ago,it was with a free 10' dish,free receiver and all the other little bits.While since that time I've bought receivers,an actuator,lnb's,etc,I have never paid for a dish(well ok the DISH 1000.2 but that's a different animal).
Now back to your regularly scheduled program.:D
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WOW you were lucky. I bought my first dish in '93 (10ft unimesh) and Monterey Chaparral 55 which I think was around $2400 or so with the internal decoder box. Loved wild feeds back in those days... everything was analog and easy to find.

...DOUG
KD4MOJ
 
SatAV_Support said:
Team,

Give me a suggestion. Should SatelliteAV offer following packages?

One MicroHD or HDVR1200 with two GEOSATpro 90cm Dishes and SL1PLL lnbfs = 299 + ship

Or for two rooms,

Two MicroHD or HDVR1200 receivers with two GEOSATpro 90cm Dishes and SL2PLL LNBFs = 399 + ship

What would make this package a value deal? Would you consider buying it if you were just starting out?

Thank you in advance,

Eugene
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My main concern would be the shipping fees which can be excessive considering the size of the dishes.
 
Two dishes. Re-iterating some of what FaT Air has said, generally 6 to 8 degrees off-centre, or off bore-sight, is the optimal range. Naturally, some satellites can be further away, while some satellites you will find, due to varying transponder strength (usually the weak one is the one you want!), can't be anything than other than bore-sight, or very close to it. I would put both 97W and 125W in that latter category, for several reasons. As has been mentioned, 125W is DVB-S2, which requires stronger signals to begin with, and, as has been noted, some even have trouble with a bore-sight signal. There is also not a lot of "play" available, as there is with DVB signals. For example, with most DVB signals (depending on FEC rate) most can drop down to around 30% quality on my AZBox without loss of signal, whereas the NBC muxes on 103W have to be above 63-64% quality to have any picture without pixelation or total loss.

As far as 97W (which also applies to a lesser extent with 125W) it is the number of transponders and the varying strength of those transponders which make it not really a good candidate for an off-centre LNB. For example, on my 80cm, I did have 97W on bore-sight with 103W six degrees off-centre, but wanted to boost the NBC muxes (as one of them was very sporadic in reception) and moved 103W to bore-sight with 97W six degrees off-centre. However, I found that the loss to some of the transponders on 97W was very significant, and ended up having neither on bore-sight, with 97W about 2 - 2 1/2 degrees off-centre, and 103W about 3 1/2 - 4 degrees off-centre. Even that small amount of change to 103W was enough to bring the sporadic transponder up to just above threshold level (63-64), most of the time!

Don't get me wrong, I have had great success in experimenting with off-centre LNBs, and using smaller dishes (for example, my 60e dishes), but various factors must be considered in the choice of satellites for off-centre LNBs. For example, I have 72W at 15 degrees off-centre on my 75e dish and get the NBC mux there with good strength, but that is a very strong transponder to begin with, is DVB, and is the only transponder on the satellite that I required, so was a good candidate for experimentation (and did free up another dish for re-pointing).
 
Agree completely with Keith. With three lnb's on the same 1 metre dish, I found 8-10 degrees offset was optimum for decent reception on offset lnb's. Location and Tp strength have to be considered.

I could never get 103 with an offset lnb from my location!

CatamountIMG_0022.JPG
 
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agreed with the above. Best I did at one time (other than the Toroidal) was 89/93/97/103 on a 36" dish so about 8 degrees each side
Lets see if I remember the setup
89 had ABCNewsNow and sports feeds
93 had Doc Scott (University Network) and feeds (this is before the satellite there had major issues and was partially replaced)
97 for obvious
103 for Pentagon (couldnt get anything else and this is when it was just the NBC feeds.....not the "cozi" stuff)
 

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Additional question regarding 125w

I have been trying to find 125W signal unsuccessfully.
Is the signal significantly weaker than other FTA satellites?
Can someone tell me the spec. for the strongest TP on the 125W.
 
My experience says that the scrambled Claro tp at 11980 V 30000 is the easiest to receive likely since it is DVB-S2 QPSK. Other tps are mostly 8PSK.
 
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