Frequency of the LNB output
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Legacy operates between 950-1450 Mhz, swtiching 13v-18v. odd/even
Dish Pro/Plus - 950-2150Mhz @ 20 volts
I think old school Direct is the same a DISH legacy.
Dish Pro/Plus - 950-2150Mhz @ 20 volts
I think old school Direct is the same a DISH legacy.
I think what you are looking for is the L.O. (Oscillating frequency) right? Stacked LNB's and switching systems oscillate at 3.1 GHz LO to make up the two sides of the band stack. Non stacked LNB's oscillate at 11.25Ghz for american legacy DBS. European Ku oscillates at 9.75Ghz or 10.6 Ghz. (hence why you can change the LO setting on a euro IRD)
These are the frequencies that actually carry the signal back to the set top box. The frequencies listed above are what comes down from the satellite. When you said the output I assumed that you wanted to know how the info travels after being manipulated by the LNB back to the receiver. I hope this helps ;0 I can verify these numbers to be correct as I have had some experience in LNB design and switching & stacking systems.
-B
These are the frequencies that actually carry the signal back to the set top box. The frequencies listed above are what comes down from the satellite. When you said the output I assumed that you wanted to know how the info travels after being manipulated by the LNB back to the receiver. I hope this helps ;0 I can verify these numbers to be correct as I have had some experience in LNB design and switching & stacking systems.
-B
BK, stacked DISH LNBFs have two LOs - one is 11.250 Ghz, other 14.350 Ghz. You can't use such low freq 3.1 GHz for convert Ku range to L.
I posted pictures of two types of DP LNBFs here - check sizes of both LO's components.
I posted pictures of two types of DP LNBFs here - check sizes of both LO's components.
On DP/DPP equipment, the frequencies are stacked as follows:
- 950-1250 MHz for Odd transponders
- 1450-2150 MHz for Even transponders
For those who are curious about D*, the frequencies are stacked as follows:
- Ka-Lo 250-750 MHz
- Ku 950-1450 MHz
- Ka-Hi 1650-2150 MHZ
Red
PS: This information comes from posts by me and others (thanks!) at SBS in this thread.
Smith P,
Hey man. Long time no chat. Hope all is well. Anyways, the end LO of the entire LNB itself may not be that for a DP/band stack, but I am sure that Dish uses a 3.1GHz high band LO to achieve their 2 bands at 950-1450 plus an inverted band at 1650-2150MHz in their dish pro frequency plan for the stacking section of their LNB. I know this based on a working model of these figures for a stacker I have to stack a legacy LNB to a dish pro one. It is possible (I have no experience in going further and combining the stacker into the switch assembly) that the stacker circuitry only responds on this frequency, but as I said I have a working unit that I use with an invacom LNB that is successfully stacking into a DPP44 and being recognized as a "Feed" on the check switch menu.. ;0 I know therefore those numbers do work for the stacking side of things 100%.
-B
Hey man. Long time no chat. Hope all is well. Anyways, the end LO of the entire LNB itself may not be that for a DP/band stack, but I am sure that Dish uses a 3.1GHz high band LO to achieve their 2 bands at 950-1450 plus an inverted band at 1650-2150MHz in their dish pro frequency plan for the stacking section of their LNB. I know this based on a working model of these figures for a stacker I have to stack a legacy LNB to a dish pro one. It is possible (I have no experience in going further and combining the stacker into the switch assembly) that the stacker circuitry only responds on this frequency, but as I said I have a working unit that I use with an invacom LNB that is successfully stacking into a DPP44 and being recognized as a "Feed" on the check switch menu.. ;0 I know therefore those numbers do work for the stacking side of things 100%.
-B
OK, BK - lets make it more deep; how we manage the freq shifting ? - mixing original freq with LO freq; now if we can easily see how freqs of even transponders will fall in range 1650-2150 with LO=14350 and same time will inverted in range, ie tp32 will have low IF and tp2 - higher.
Now if you could show me your math, how to use LO < Fin and transpone those 12.2-12.7 into 1.65-2.15 with inversion. No way man !
Now if you could show me your math, how to use LO < Fin and transpone those 12.2-12.7 into 1.65-2.15 with inversion. No way man !
Hey, unfortunately, I am no guru at the math behind the L.O. I would actually love to learn the math behind LO versus source state. I only know what the spec sheet I have says for the device and that it works as I have been using it for close to two years now... beyond that I can't tell you much. The numbers DO seem low to me, I expect it to at least be above 10 ghz.
But, I cant argue with a company that made me a working product to stack legacy into DP. I gave a company what I wanted to be designed as best I could explaining how I wanted the end result (the end band stack, putting both even and odd into 950-1450 chunks then band stacking one on top of the other to get an end 950 -2150 mhz) and they gave me those numbers, and a spec sheet and two prototypes that worked. I would be happy to take a picture as proof and share the sheet's specs with you...?
Maybe you can make better sense of those numbers than I can? ;0 Not trying to argue with you, I respect your skills more so than my own without question, but I also cant argue with what is written in front of me from an engineer that designed a working product? ;0
I would be happy to remove any trace of my name and PM you the design specs. drop me a PM sometime. I would be interested to actually figure the math out behind this. I believe the inversion I referenced is taking a chunk of 950-1450 (the IF in this instance) and putting it in the 1650 - 2150 range. The end result obviously can't be inverted. (It would end up in the upside down state you explained) The inversion instead references the original state versus the end state here. It needs manipulation to be put into the stack. The end state is an inversion of the source state.
-B
But, I cant argue with a company that made me a working product to stack legacy into DP. I gave a company what I wanted to be designed as best I could explaining how I wanted the end result (the end band stack, putting both even and odd into 950-1450 chunks then band stacking one on top of the other to get an end 950 -2150 mhz) and they gave me those numbers, and a spec sheet and two prototypes that worked. I would be happy to take a picture as proof and share the sheet's specs with you...?
Maybe you can make better sense of those numbers than I can? ;0 Not trying to argue with you, I respect your skills more so than my own without question, but I also cant argue with what is written in front of me from an engineer that designed a working product? ;0
I would be happy to remove any trace of my name and PM you the design specs. drop me a PM sometime. I would be interested to actually figure the math out behind this. I believe the inversion I referenced is taking a chunk of 950-1450 (the IF in this instance) and putting it in the 1650 - 2150 range. The end result obviously can't be inverted. (It would end up in the upside down state you explained) The inversion instead references the original state versus the end state here. It needs manipulation to be put into the stack. The end state is an inversion of the source state.
-B
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Wow, I'm struggling to understand some of what you guys are talking about. But keep it up! I'm putting some of the pieces together.
