C-Band questions
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Iceberg said:
Usually between 40 and 50% depending on the weather, which is good. Last month they had a major snow storm in Anchorage and they were down for about 3 days. Let me know and give me some time to brush up on C band lingo.
cool. I should get around a 75 then with the Pansat
Jim, I'll give you some time
I was thinking of building this x-mas weekend
Jim, I'll give you some time
I was thinking of building this x-mas weekend
Okay, that sounds good. Bare with me, I screwed up and got a job so now I don't have as much time to mess with this stuff as I used to. Retirement was great while it lasted. Go ahead and fire me any questions you have, I do try to check in everyday. You are gonna love this thing. 
Barry wrote:
> Where I work, all of the newer C-Band dishes we have are not prime focus, <
That's surprising. While I knew that offset-C dishes existed, I thought they were quite rare. What size are those dishes?
- Tim
> Where I work, all of the newer C-Band dishes we have are not prime focus, <
That's surprising. While I knew that offset-C dishes existed, I thought they were quite rare. What size are those dishes?
- Tim
OK...went home and actually looked at this LNB and stuff....this is what I figured out
(I was looking at it like I would a KU LNB...so I got confused)
There are 4 rings with something right in the middle of it. I'm assuming this is what collects the signal. On the back end, is a blue box. The writing on it says
Drake 2775 Low Noise Block Amplifier....There is one output on it. This has to be the C-band LNB...or is it a LNBA?
There is a spot for a KU LNB...that is a separate piece and say "Saarn LNB 600 low noise converter" also with a single output
The only other thing on this setup is 3 wires (red, white, black) coming off the bottom of a box that say "3 wires pulse"
Another question...we were talking about the elevation is legit on prime focus dishes....how much of an angle is the signal reflected off of to hit the LNB? What I mean is, I took some measurements on my deck to see how big this is and it's gonna take up a fair amount of my deck
The LNB at about a 40 degree angle will clear the roof. The true south birds for me (G11, T6, G3) are around 39....I wonder how low of an elevation I can get and still not hit the roof
(I was looking at it like I would a KU LNB...so I got confused)
There are 4 rings with something right in the middle of it. I'm assuming this is what collects the signal. On the back end, is a blue box. The writing on it says
Drake 2775 Low Noise Block Amplifier....There is one output on it. This has to be the C-band LNB...or is it a LNBA?
There is a spot for a KU LNB...that is a separate piece and say "Saarn LNB 600 low noise converter" also with a single output
The only other thing on this setup is 3 wires (red, white, black) coming off the bottom of a box that say "3 wires pulse"
Another question...we were talking about the elevation is legit on prime focus dishes....how much of an angle is the signal reflected off of to hit the LNB? What I mean is, I took some measurements on my deck to see how big this is and it's gonna take up a fair amount of my deck
The LNB at about a 40 degree angle will clear the roof. The true south birds for me (G11, T6, G3) are around 39....I wonder how low of an elevation I can get and still not hit the roof
This may help the "members" visualize the difference between prime focus and offset dish..... I know its only a link to a web site but a link is worth a thousand words sometimes : )
http://www.satsig.net/azelhelp.htm
http://www.satsig.net/azelhelp.htm
The rings are called scaler rings...Its an Lnb, what temp does it say? The 3 wires are to switch polarity from H to V.
What do you mean temp? Thats all that was on there besides the serial number and 14-24 volts
ok. so those 3 wires then would have to be hooked up...got that part
ok. so those 3 wires then would have to be hooked up...got that part
The temperature is the way they measured the gain or strength of... My first BUD came with an lna that was 120 degrees. When I went to a dual feedhorn and an Lnb and GI 2000 ird i went to a 75. The ones on both of my Buds now are 25's.
Iceberg,
> The only other thing on this setup is 3 wires (red, white, black) coming off the bottom of a box that say "3 wires pulse" <
That's the servo-motor, that drives the polarotor, controlling the angle (polarity) of the probe. They can set it to H/V or anywhere in between, in small increments.
> how much of an angle is the signal reflected off of to hit the LNB? <
None. I.e., the satellite will be perpendicular to the face of the dish.
> The LNB at about a 40 degree angle will clear the roof. The true south birds for me (G11, T6, G3) are around 39....I wonder how low of an elevation I can get and still not hit the roof <
If this is accurate, then you're hosed, unless you raise the dish, or lower your roof. You MUST have a clear view of the satellites, even if it's only a 1-2 degree clearance. 1-2 degrees the other way and you're SOL. The entire arc will be below your "horizon". If you were just "eye-balling" it though, I wouldn't be pessimistic until you make an actual measurement. 39 degrees is a lot higher than it might seem, and unless you have tall objects very close to the dish, you might be surprised what you can clear.
> Drake 2775 Low Noise Block Amplifier <
Sounds like an old-fashioned LNBA. Should have some very thick coax running 4 GHz to a block downconverter to the 950-1450 range, then standard RG6 running out of that.
- Tim
> The only other thing on this setup is 3 wires (red, white, black) coming off the bottom of a box that say "3 wires pulse" <
That's the servo-motor, that drives the polarotor, controlling the angle (polarity) of the probe. They can set it to H/V or anywhere in between, in small increments.
> how much of an angle is the signal reflected off of to hit the LNB? <
None. I.e., the satellite will be perpendicular to the face of the dish.
> The LNB at about a 40 degree angle will clear the roof. The true south birds for me (G11, T6, G3) are around 39....I wonder how low of an elevation I can get and still not hit the roof <
If this is accurate, then you're hosed, unless you raise the dish, or lower your roof.
You MUST have a clear view of the satellites, even if it's only a 1-2 degree clearance. 1-2 degrees the other way and you're SOL. The entire arc will be below your "horizon". If you were just "eye-balling" it though, I wouldn't be pessimistic until you make an actual measurement. 39 degrees is a lot higher than it might seem, and unless you have tall objects very close to the dish, you might be surprised what you can clear.> Drake 2775 Low Noise Block Amplifier <
Sounds like an old-fashioned LNBA. Should have some very thick coax running 4 GHz to a block downconverter to the 950-1450 range, then standard RG6 running out of that.
- Tim
Yes, it has been so long since I ran that...my lna had the same going to the blockdowncoverter... Here they are, on top the Amplica 120degree lna, middle the Sat tec receiver and botton the downconverter...VideoGrabber said:
OK...checked it out again. Here is what is on it (all of it)
The box is blue and is a Drake low noise block amplifier
Noise Temp 50 degrees K
3.7-4.2 ghz input
950-1450 mhz output
+14-+24v dc supply
so it sounds like a LNBA which should still work
The box is blue and is a Drake low noise block amplifier
Noise Temp 50 degrees K
3.7-4.2 ghz input
950-1450 mhz output
+14-+24v dc supply
so it sounds like a LNBA which should still work
what options are there besides H & V?VideoGrabber said:
that was kind of a stupid question
I was eyeballing it by using my DirecPC dish which is at 38. Now that I understand the offset, it should clear. But how much of the dish has to clear the roof? If I set it on my deck, about the bottom 1/4 will be blocked by the roof...it sounds like I'm screwed.> The LNB at about a 40 degree angle will clear the roof. The true south birds for me (G11, T6, G3) are around 39....I wonder how low of an elevation I can get and still not hit the roof <
If this is accurate, then you're hosed, unless you raise the dish, or lower your roof.
The cable that came with it is very thick and heavy and also for the motor.. Looks like it has cable . It was about 100 feet and had some good weight to it
WOW, dfergie, I havent seen one of those ancient things since I had my old BUD in the early 80's. Those old 70MHz single conversion converters sure had a tendency to drift all over the place, didnt they. I finally got fed up and bought a Drake ESR-??? (their first block conversion satellite reciever) and a drake block converter with a male 'N' connector right on the case (the whole case threaded into the LNA) Boy, those were the days....
That was my "new box" the older one was in a grey box with no labels... still have downconverters one 120 lna and 2 receivers...and yes they drifted, I frequently opened them up and adjusted the "pots" inside with a little screwdriver...Only thing was I cut up the feedhorn to try to hook a dbs lnb too with no successOregonboy1971 said:WOW, dfergie, I havent seen one of those ancient things since I had my old BUD in the early 80's. Those old 70MHz single conversion converters sure had a tendency to drift all over the place, didnt they. I finally got fed up and bought a Drake ESR-??? (their first block conversion satellite reciever) and a drake block converter with a male 'N' connector right on the case (the whole case threaded into the LNA) Boy, those were the days....
Can we say sparklies...BTW this setup used an antenna rotator to go from H to V, a hand crank and the primitive box...- Status
