If all you need is a standard LNB, is there any downside to using a universal LNB?
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"Why" would you want a Universal LNB. What more will it get you?
They do limit you switch options, as they use a 22KHz tone to go between Hi and Low bands.
They do limit you switch options, as they use a 22KHz tone to go between Hi and Low bands.
I thought there was a setting that speed up blind scan on universals?
Something about turning on the 22 tone or something?
Something about turning on the 22 tone or something?
You are correct, set the 22 tone to allow the high band only, I believe it is 10600 for a Universal, this way you will speed up the scan and you will not duplicate the channels in some cases.
not an option if you choose universal,that option is greyed out.
you have to choose standard 10600 then turn 22khz on.
for openbox receivers, standard ku linear is better,especially on motorized diseqc1.2 setups.
you have to choose standard 10600 then turn 22khz on.
for openbox receivers, standard ku linear is better,especially on motorized diseqc1.2 setups.
I don't think this matters in regards to BLIND SCAN or BLIND SCAN speed. Why would a UNIVERSAL LNBF slow down the scan speed in this light? To me it doesn't make any logic, unless I am missing something.
Most receivers that I am familiar with do not allow you to have multiple bands selected for the same satellite (i.e. you cannot select 5.250 as a L.O. and 10.750 for the same satellite nor 9.750 and 10.600 for the same satellite). Even though multiple bands may be available on that one sat, you cannot configure your receiver to accommodate it as such. If the sat has C-Band Signals and Ku-band signals as well, you cannot program the receiver to utilize two different local oscillator freqs to accommodate this. You would have to create two indivisual satellites (one for C and one for Ku as two separate sats). Same with low and high band Ku.
Therefore, if you scan the C-Band sat, or the Ku Band sat or the Hi vs Low Ku band sat... whenever you perform a blind scan, you have to be scanning only one band at the time. So, why would it require longer? I don't think that this analogy is accurate in the way that it is stated. Certainly, it does require longer, because in essence, you are scanning two satellites. So, you have to stop after the first scan of (lets say the C-Band broadcasts from one sat) and then repeat that scan for the Ku band side of the same sat. Or do the same for HI and LOW band KU.
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Most receivers that I am familiar with do not allow you to have multiple bands selected for the same satellite (i.e. you cannot select 5.250 as a L.O. and 10.750 for the same satellite nor 9.750 and 10.600 for the same satellite). Even though multiple bands may be available on that one sat, you cannot configure your receiver to accommodate it as such. If the sat has C-Band Signals and Ku-band signals as well, you cannot program the receiver to utilize two different local oscillator freqs to accommodate this. You would have to create two indivisual satellites (one for C and one for Ku as two separate sats). Same with low and high band Ku.
Therefore, if you scan the C-Band sat, or the Ku Band sat or the Hi vs Low Ku band sat... whenever you perform a blind scan, you have to be scanning only one band at the time. So, why would it require longer? I don't think that this analogy is accurate in the way that it is stated. Certainly, it does require longer, because in essence, you are scanning two satellites. So, you have to stop after the first scan of (lets say the C-Band broadcasts from one sat) and then repeat that scan for the Ku band side of the same sat. Or do the same for HI and LOW band KU.
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I have a universal on my AMC 6 dish and my Pansat 9200 scans a portion of vertical and horizontal a second time with it. My 3 other ku dishes have the original Primestar standard lnb's and it only scans each polarity once on those, taking less time. I always thought this was because the universal has a wider frequency range.
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Universal LNBFs have two bands with a built-in 22KHz switch. The first band is low with LO 9750MHz with 22KHz switch off and covers 10.7 - 11.7GHz. The second band is high with LO 10600 and covers 11.7 to 12.75GHz. Even with the receiver set to LO 10600 and 22KHz on, the receiver will scan the entire 11.7 - 12.75GHz range.
Standard LNBFs may be designed to cover 11.7 - 12.75GHz while others cover only the FSS band of 11.7 to 12.2GHz. If the LNB has an LO frequency of 10750, the receiver will scan and log transponders between either 950 - 2100 or 950 - 1450.
If a receiver does not have the option to set a start and a stop frequency, it will typically scan the entire IF frequency of 950 - 2150. If the LNB has the ability to receive frequencies outside of the desired band, the scan will take much longer as more bandwidth will require processing.
Be sure to know the bandwidth of the LNB and understand how your receiver will interact. If the LNBF covers a limited range of 11.7 - 12.2 or the STB blind scan range can be limited, a scan will be much faster.
Standard LNBFs may be designed to cover 11.7 - 12.75GHz while others cover only the FSS band of 11.7 to 12.2GHz. If the LNB has an LO frequency of 10750, the receiver will scan and log transponders between either 950 - 2100 or 950 - 1450.
If a receiver does not have the option to set a start and a stop frequency, it will typically scan the entire IF frequency of 950 - 2150. If the LNB has the ability to receive frequencies outside of the desired band, the scan will take much longer as more bandwidth will require processing.
Be sure to know the bandwidth of the LNB and understand how your receiver will interact. If the LNBF covers a limited range of 11.7 - 12.2 or the STB blind scan range can be limited, a scan will be much faster.
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Once you get started in this hobby, I think you'll want access to more than just one satellite.
Brian,
I was indeed missing something in my last reply. Specifically how you program the LNBF type or the L.O. frequency within the IRD setup menu. It depends upon what options you have to select from within the IRD menus. But, I may have been hitting on a nice trick without realizing it. If your IRD has the option to select a "USER PRESCRIBED L.O. FREQUENCY", you can bypass or omit a portion of the full Ku band from being scanned during a blind scan by NOT selecting UNIVERSAL as the LNBF type.
If a satellite has all HIGH Ku band transmissions, and the IRD allows for the option, you can select the L.O. in the menus as 10.600 and the 22KHz signal ON. During a blind scan, the IRD should only scan 11.7 - 12.2 (or 12.75)
If a satellite has all LOW Ku band transmissions, and the IRD allows for the option, you can select the L.O. in the menus as 9.750 and the 22 KHz signal OFF. During a bind scan, the IRD should only scan 10.7 - 11.7.
If the satellite has a mix of both upper and lower Ku band transmissions, then (to get all) you would select the UNIVERSAL LNBF or the 9.750/10.600 L.O. option in the setup menu with the 22KHz set to AUTO. During a blind scan, the IRD should scan the entire gambit from 10.7 - 12.7 (12.750) MHz.
Therefore, what I am thinking is that the scan time would only be lengthened when you performed a blind scan of a satellite that included both LOW and HIGH Ku band signals. For satellites that you know are all one or the other, you could shut the other band (the other L.O.) off entirely and the IRD would not bother scanning the full range.
I guess what I had in mind was that a person would not have to select UNIVERSAL as the LNB type for every satellite configuration if you were availed the option to set a USER PRESCRIBED L.O. frequency. This would, of course, depend upon the options available to the user from the menus of the IRD. I know you can do this with the AZBox.
If the IRD allows for this, you would be able to customize the use of the UNIVERSAL LNBF and "deselect" one of the L.O.'s at will when appropriate or desired or applicable. In other words, why scan the entire Ku band (HI and LOW) if you already know that the satellite only offers one or the other. You can omit "the other" band automatically in the setup parameters and speed up the scan time.
For most of us in North America, we could opt to program our IRD's (while a UNIVERSAL Ku band LNB is installed) so that the IRD thinks we have a single LNB with a L.O. frequency of 10.600 GHz (for the HIGH band Ku which would be a typical signal).
Since a UNIVERSAL LNB is just two LNB's in one assembly that you select from via the 22KHz tone. You don't always have to use BOTH if it is not desired or required.
The drawback that I see however, is that most of the UNIVERSAL LNBF's I have looked into don't have multiple outputs to feed multiple receivers. And, beyond that, when I looked into LOW Ku band signals for North America, there really wasn't all that many up there.
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some old receivers like the coolsat let you tweak the range for blindscan to whatever you wanted,as long as it was within range of the lnb.Most of the time I would set it to scan 11700 to 12200 instead of the default 10700 to 12750
With the openbox I set the lnb type to standard 11600 22khz on,so it scans 11700 to 12750,not as fast but better than the full range of 10700 to 12750.
universal lnbs were often bundled with a big dish/brackets because they were cheaper than the standard ku.
With the openbox I set the lnb type to standard 11600 22khz on,so it scans 11700 to 12750,not as fast but better than the full range of 10700 to 12750.
universal lnbs were often bundled with a big dish/brackets because they were cheaper than the standard ku.
Yes, in this case that is the function that it (the switch) performs. With the 22KHz tone ON, it selects or activates the L.O. with the 10.600 GHz frequency. When OFF, it defaults to the 9.750 GHz local oscillator. So, basically you have two L.O.'s in the same unit and that makes it operate as if it were two LNBFs, one for the low band Ku signals and one for the high band Ku signals. It is all one physical assembly, but has the two separate local oscillators which makes it function like two LNBFs.
Like HIGH and LOW headlight beams on your car or truck. Click the switch to route the signal through one relay and you have low beams, click it again and you get high beams. Both from the same lamp in the front of the vehicle. That's kind of a loose comparison or analogy, but you get the point.
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