Mounting 2nd lnb for 103.0W ?
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I'm having brain failure tonight. If mounting second lnb on motorized dish, the switch goes after the motor, In the coax line going to lnb's? Don't I need a 22khz switch rather than diseqc switch?
If your only using two LNBF's, either one will work. Just have to set it up in your receiver.
Thanks ke4est. I was sitting here tonight and drew a complete blank on where the switch went in the mix. Thanks
Just to clarify for those looking to put a secondary LNBF next to the main LNBF for reception of 103W on a motorized dish:
Remember that, because the dish bounces the signal, the secondary LNBF is mounted opposite of the way the satellites are arranged in the sky. For example, if you want to hit a secondary satellite that is in an orbital position East of where the main LNBF is aimed, you would mount the secondary LNBF WEST of the main LNBF, and vice versa.
It is probably best to put the secondary LNBF to the WEST of the main LNBF. The reasoning behind this is that some LNBFs protrude downward where the coax is connected, and that protrusion would hit the main LNBF when skewed to the East for 103W if the secondary LNBF was mounted to the East of the main one. This is probably a moot point with "bullet" LNBFs and some other designs, as they do not have a protrusion and are more or less totally cylindrical.
If the secondary LNBF is mounted West of the main LNBF, you would want to either add a dummy satellite at 109W or change the coordinates of 103W to 109W. If you mount the secondary LNBF East of the main LNBF, it will be receiving 103W when the main LNBF is at 97W.
Hope this helps...
Remember that, because the dish bounces the signal, the secondary LNBF is mounted opposite of the way the satellites are arranged in the sky. For example, if you want to hit a secondary satellite that is in an orbital position East of where the main LNBF is aimed, you would mount the secondary LNBF WEST of the main LNBF, and vice versa.
It is probably best to put the secondary LNBF to the WEST of the main LNBF. The reasoning behind this is that some LNBFs protrude downward where the coax is connected, and that protrusion would hit the main LNBF when skewed to the East for 103W if the secondary LNBF was mounted to the East of the main one. This is probably a moot point with "bullet" LNBFs and some other designs, as they do not have a protrusion and are more or less totally cylindrical.
If the secondary LNBF is mounted West of the main LNBF, you would want to either add a dummy satellite at 109W or change the coordinates of 103W to 109W. If you mount the secondary LNBF East of the main LNBF, it will be receiving 103W when the main LNBF is at 97W.
Hope this helps...
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I went on line to find this, sorry about it being so small, but in this example, the main LNB would be the one on the left, you can see the arm from the dish coming out the top towards the bottom of the dish, and I would suppose that for this example the LNB would be at the 0 position. IF that were so, then the LNB on the right would be rotated about until it received the signal on 103.
In this example, the main dish would probably be pointed at something like 95~90 while the LNB on the RIGHT would be bouncing a signal from 103. I say this because the LNB on the right is bouncing ACROSS the dish and receiving a signal from somewhere WEST of the main LNB.
If the secondary LNB was on the WEST side of the main LNB it would be receiving a signal EAST of the main LNB.
I'm not a teacher so I may not be going about this properly, however, imagine if you would that for explanation purposes ONLY, the extension on the LNB on the right in this picture was 8" or 12" further away from center than shown, can you see how the LNB would be pointing further and further away from the center of the dish, thus receiving a signal (if this were possible) from further and further WEST of the main LNB.
I can't draw lines on this picture, maybe someone already has an example of what I am trying to say.
Photto
In this example, the main dish would probably be pointed at something like 95~90 while the LNB on the RIGHT would be bouncing a signal from 103. I say this because the LNB on the right is bouncing ACROSS the dish and receiving a signal from somewhere WEST of the main LNB.
If the secondary LNB was on the WEST side of the main LNB it would be receiving a signal EAST of the main LNB.
I'm not a teacher so I may not be going about this properly, however, imagine if you would that for explanation purposes ONLY, the extension on the LNB on the right in this picture was 8" or 12" further away from center than shown, can you see how the LNB would be pointing further and further away from the center of the dish, thus receiving a signal (if this were possible) from further and further WEST of the main LNB.
I can't draw lines on this picture, maybe someone already has an example of what I am trying to say.
Photto
Blindowl,
Installing the switch between the motor and the LNBF's is indeed the recommended arrangement.
As for the switch type, I know that a DiSEqC switch will work and work well as this is what I used.
However, a standard 22kHz switch may not pass the necessary tones or pulses on through to the LNBF/s to switch between one L.O. and another.
If your LNBF/s have only one L.O., then either the 22KHz or the DiSEqC switch will work. But, if you have a universal LNBF, you may find that some 22KHz switches won't be compatible.
You may need to scrutinize the actual make / model of 22KHz switch at hand to determine of it will function with your selected LNBF.
An ECODA 22KHz switch is unique in that it will pass the tones on through the switch, so it can be used.
RADAR
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Tron,
Installing the secondary 103° LNBF to the west of the main LNBF definitely sounds to be the best practice. Not only does this eliminate the possibly of the 103 LNBF from hitting the main LNBF (imagine trying to do this on the east side with an Invacom QPH-031!) But, using the "dummy" 109 satellite is an excellent idea since there isn't any bird there anyway.
RADAR
Tried it today on the dish I installed for my son and the modified bracket (flat bar stock) it worked. I think I'm going back to using just one lnb though as I didn't see any noticeable improvement in signal. I think I'll try the Geosat Pll and see what happens with it. My old motorized 36" Primestar dish does fine on 103w with just a Geosat Pll lnb. I've never adjusted it for the skew on 103W.
Is It Worth It?
How much difference can it really make to turn the LNB by 26 degrees? The cosine of thirty degrees is 87% so we are talking about a loss of signal of only 11 or 12% without turning the LNB. Most of the Ku signals on that bird are pretty weak anyway.
How much difference can it really make to turn the LNB by 26 degrees? The cosine of thirty degrees is 87% so we are talking about a loss of signal of only 11 or 12% without turning the LNB. Most of the Ku signals on that bird are pretty weak anyway.
How much difference can it really make to turn the LNB by 26 degrees? The cosine of thirty degrees is 87% so we are talking about a loss of signal of only 11 or 12% without turning the LNB. Most of the Ku signals on that bird are pretty weak anyway.
I can tell you this: Without that "special" 26 degree skew, I can NOT receive any of the NBC transponders on this satellite at my location, even with a 1 meter Primestar dish. So, YES, it can make a big difference, UNLESS the user is dead middle of the footprint, OR has at least a 1.2 meter KU dish.
Hmm, that's good to know...
Maybe I will add an LNB to my setup too. It doesn't cost much.
Thanks.
Maybe I will add an LNB to my setup too. It doesn't cost much.
Thanks.
It makes a noticeable difference with the NBC stuff. For some reason, not so much with other TPs.
Yes, the notion was explained to me quite a while back because I didn't detect the difference, either.
Well, the point being, if you didn't know WHAT you were missing, you wouldn't miss it.
RADAR
Well, the point being, if you didn't know WHAT you were missing, you wouldn't miss it.
RADAR
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:Small break through. I was finally able to receive COZY TV channel via the 103.0 W satellite. Unfortunately my signal quality is low and it fluctuates between 40 - 55 on my micro HD. The result is video pixellation issues. My 2nd lnb is currently mounted to the left of my primary lnb - when facing the dish. I was wondering if mounting the 103.0 W lnb to the right of my primary lnb would be worth a try. I need to get my signal quality up to watch this channel. I believe I have tweaked the skew of the lnb to optimize my signal gain. Also, if anyone in the Boston area is receiving COZY TV via 103.0W could you please let me know what your signal levels are and what size dish you have? Any suggestions would be appreciated. Thanks
Cebu,
You will theoretically have the same reception possibility if the 2nd LNBF is to the right or left of the primary LNBF, that should not matter. Being on the left, you should have more options and convenience to play with the mechanical positioning of the 103 LNBF because you should have more "physical" room to manipulate the LNBF. This, of course, is based upon the physical dimensions and shape of both LNBFs. As was stated earlier in the thread, if you are using the "bullet" LNBFs, it really doesn't matter much.
Since you are now at least able to detect the channel, you can try adjusting the orbital degree of the satellite in your receiver menus. If using USALS and if you told the receiver that 103°W was at 109°W, try 109.2°W or 108.8°W and see if the signal quality goes up or down. You can keep adjusting this until you optimize the signal quality. If you are using DiSEqC motor control, just step the motor to peak the signal.
Then, you can also try moving the LNBF away from or closer to the dish in the mounting bracket to adjust and optimize the focal point.
If this is a homemade bracket for the second LNBF, you can try adjusting the position of the LNBF in some other axis, if possible. Like the height or the swivel angle if you have provisions to do so.
Remember that any adjustments you make to any one axis may affect the optimum adjustment of another axis, so you may have to experiment with several adjustments at one time. Best to write notes on this as you go. Record the quality reading for each adjustment you make and what that adjustment was so that you can backtrack your way to the optimal setting that you found.
RADAR
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Cebu,
Here is a secondary note from me. If you want to know the best possible quality signal you can obtain from the COZY channel on 103°W, try this...
Rotate your primary LNBF polarization (or skew) about 26° CW when standing in front of the dish. Then drive your motor using USALS or DiSEqC control to 103°W as you would normally do for any other satellite and take your quality reading there, using the primary LNBF as your reception device. If your motorized dish setup angles (dish elevation, motor latitude and LNBF polarization) are all set to the optimum performance, then you can use that quality reading as your guide when installing and aligning your secondary "sidecar" LNBF.
If you record a signal quality strength of 68% from the TP on 103°W which carries the COZY channel, and that is the max you can get with the primary LNBF, then you should not expect to exceed that with your secondary "sidecar" LNBF, but you can strive to come somewhere near that. Basically, this gives you a goal to aim for.
RADAR
Here is a secondary note from me. If you want to know the best possible quality signal you can obtain from the COZY channel on 103°W, try this...
Rotate your primary LNBF polarization (or skew) about 26° CW when standing in front of the dish. Then drive your motor using USALS or DiSEqC control to 103°W as you would normally do for any other satellite and take your quality reading there, using the primary LNBF as your reception device. If your motorized dish setup angles (dish elevation, motor latitude and LNBF polarization) are all set to the optimum performance, then you can use that quality reading as your guide when installing and aligning your secondary "sidecar" LNBF.
If you record a signal quality strength of 68% from the TP on 103°W which carries the COZY channel, and that is the max you can get with the primary LNBF, then you should not expect to exceed that with your secondary "sidecar" LNBF, but you can strive to come somewhere near that. Basically, this gives you a goal to aim for.
RADAR
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