LNB's and LNBF's

[123tim]

This is probably a stupid question, but....
In doing some research I found out what the "F" in LNBF stands for. I had been wondering about this in the past and sort of forgot about it. F stands for feedhorn, which I'm sure that everyone but me knew. My question is this - don't all LNB's which are used in FTA have the feedhorn built in? When we use the term LNB do we really mean a LNBF? Were there LNB's that used a separate feedhorn at one time?
When I first started out (knowing even less than I do now), I remember wondering what the difference was between a LNB and a LNBF, and which I needed to buy.
I guess this grew from one stupid question to several stupid questions. I guess the world won't end if I don't get a reply right away

 

[Mr Tony]

Most FTA LNB’s (or I guess LNBF’s) have a feedhorn built in
The older C-band ones were LNB’s and you could take the back end of the unit off with 4 screws and swap it out with a lower noise figure and still keep the main part that aims at the dish.
Most people just use LNB as the name (even though it’s a LNBF) : )

Below are the differences...the first is a LNB, the 2nd a LNBF (these are for C-Band)

 

[123tim]

Thanks Iceberg. Seems like I missed out on a lot of knowledge not being around when C-band was king. FTA must be getting more streamlined and and user friendly now. Not always a good thing

 

[voomvoom]

When I first started. I had a hand crank to move the dish. It had a rotor (like most people have to move there OTA antenna's with) to change the polarity. And, it had an LNA. Can you guess what it stood for?
Well, never mind, I'll tell you. Low Noise Amplifier....

Al

 

[ken2400]

Oh ya the old LNAs. I bought some used stuff back around and remember LNAs. Don't for forget the downconverter. LNB's have them build in. There was something about 70 that comes to mind. I forgot tho.

When I first started. I had a hand crank to move the dish. It had a rotor (like most people have to move there OTA antenna's with) to change the polarity. And, it had an LNA. Can you guess what it stood for?
Well, never mind, I'll tell you. Low Noise Amplifier....
Al

 

[voomvoom]

Darn, I had forgotten about the downconverter. The only thing 70 I can think of, would be maybe a 70 degree LNA. Seems like my first one might have been a 120 degree LNA.

Al

 

[123tim]

This is my thread, I can diverge it can't I?
Since it's cool to look back:
(A) What year did Neiman Marcus sell a satellite system for $36,000?
(B) Does anyone know who the name of the first individual to receive C-band satellite signals on a homebuilt satellite system?
(C) Do you know when the first Satellite TV transmission occurred?
(D) Do you remember your first system?



Not yet.
Not yet.
Not yet.





Ok. now.




A -1979
B- Taylor Howard (1976)
C-1962
D-
These answers were found here:
http://www.sbca.com/key_dates.html

 

[voomvoom]

a) Don't remember him, but I saw (but couldn't afford) a Zenith Satellite System for $6000. Ouch.... In the late 70's, I was making maybe twice that in a year's time.
b) Don't remember the name so I can't vouch for him (Taylor Howard), but I know I heard/read about somebody years ago.... (late 70's again)
c) I was thinking Sputnik was in the late 50's.... I may be wrong, but it's what I think. Ooops, you said TV didn't you. Nope, don't have a clue.
d) Not only do I remember it, I still have it, updated, modified, refitted, cussed at, but mostly appreciated.

Al

 

[123tim]

Al,

So when did you get your first system?
Neiman Marcus is a high-end catalog store sort of like.....well......really, I don't know.
I hope that I can always update, refit and modify my system. Brand new now, but not for long.
Take care.

 

[voomvoom]

Not totally sure, but it was either 78 or 79.

Al

 

[mbarnes]

Back in the old days, there were LNAs and downconverters. Microwave circuits were very expensive and very touchy. The circuitry common in todays wireless phones (800/900/1200MHz) cost thousands of dollars and would be fairly large and cumbersome. So, early satellite systems used a 70 MHz If frequency. The receiver sent a signal to the downconverter to switch between transponders.

Today's technology is much better. Now there are LNBs which have a preamplifier and a block converter all in one package, and use a much higher IF frequency, typically L-band or 970-1250 MHz. With this wide range, the entire satellite bandwidth is available to the receiver with no external switching.

There are many types of dishes and feed systems available. Some feedhorns are capable of holding several LNBs. Mostly the advent of DBS/DSS systems made it much cheaper and easier for installations to have a combined LNB and feedhorn, hence the LNBF. But there are still many applications using separate LNBs and feedhorns.

I've got a few old Ku band LNBs kicking around that are as big as typical C-band LNBs. The newest ones are 1/4 the size.

BTW, the RF package on our uplink system still uses an LNA and downconverter feeding the indoor package with a 70 MHz IF.

 

[Tron]

I've got a Unimesh buttonhook and LNA sitting in my shed Well, the LNA isn't Unimesh, but the buttonhook is. The LNA has a large (N-type?) connector on it, and there's a cable that goes from it to another unit which is attached to the LNA with electrical tape (the downconverter?) I got these when a neighbor threw his BUD out a few years ago (before I got into Ku FTA). The mesh dish was hopelessly bent and corroded, but the buttonhook and LNA where in fine shape. There's also a polarotor... Might come in handy someday

 

[bruce005714]

Linear and Circular LNB

I am new to FTA world. I still did not get good information about linear and circular LNB. Generally people said, linear LNB for FTA , circular LNB for dish netwrok. Can I use Linear LNB for dish network? Also, circular LNB can be used for FTA?
I'm a little bit dull.

 

[PSB]

No! You will need a linear LNBF for 95% of KU signals FTA
And a Circular LNBF for the very few FTA channels on Dishnetwork.

Have a look at the below pictures.......

WELCOME to the SatelliteGuys.US FTA forum!

 

[jayelem]

My First (only) C-band Dish was a Birdview.

Back in 1985-86 I convinced Mom to get a BUD, some premium channels were still in the clear, but that didn't last long, I think at that time Al Gore was defending the rights of consumer satellite groups.

Anyways because I was 15 and remember feeds from Global or World something like that, I remember syndicated shows playing for hours in a row, sometimes with no commercials or a space of time all black, was very cool, long before Cartoon Network, where else could you watch Inspector Gadget and Thundercats at Midnight and into the morning hours.

Can also remember stuff I shouldn't be watching, like channel 24. SAT ????

Our system was professionaly installed, and stayed with the house after we moved in 1990, 6 months ago my brother showed up at the house with our old dish, nice white spun aluminum, feeder legs were hacked off and I doubt the motor works, I considered putting it up, but don't feel up to the challenge of modifying it, also could be warped, didn't do the string test, still have it and thinking of taking it to the scrap metal yard. The current owners had it pointing straight up and had planted flowers in it.

At 15 I didn't really know what money was, Mom paid around $ 2000 +, hard to believe someone paid $36,000 for one, guess cable TV wasn't available back then.

As for LNB'S I remember something about them being Cool or Hot, Anyone ???

 

[ken2400]

Well lets see if I can talk you into playing with it.

If you still have the orig receiver you can use it to test out the motor. Also there is enought analog stuff up there to test both the receiver and LNB. If your receiver has a auto scan, change the channel/transponder until you get signal once you get the dish pointed at something. Go out on a calm day and prop the dish up next to a wall, picnic table or what ever. Pick a sat with some analog stuff you can see. If the mount is still good then angle the dish until the the pole mount is plum with the earth. Just think of a real short poll and you can trying to put it on it but the edge is hitting the ground. Once you do this then move it right to left until you get a signal. It was on a sat when it was pulled down. There should be a sat in the same spot. If you can get it on a poll all the better.

If you still have most of the feed arm lenght then rig them up to support the LNB and feedhorn.

A in-line signal meter will help. If you have to test it with digital stuff it might take longer.

If it all sound like too much then give it a way in the classified forum. Spun aluminum make a nice dish when it comes to getting signal.

Back in 1985-86 I convinced Mom to get a BUD, some premium channels were still in the clear, but that didn't last long, I think at that time Al Gore was defending the rights of consumer satellite groups.
Anyways because I was 15 and remember feeds from Global or World something like that, I remember syndicated shows playin for hours in a row, sometimes with no commercials or a space of time all black, was very cool, long before Cartoon Network, where else could you watch Inspector Gadget and Thundercats at Midnight and into the morning hours.
Can also remember stuff I shouldn't be watching, like channel 24. SAT ????
Our system was professionaly installed, and stayed with the house after we moved in 1990, 6 months ago my brother showed up at the house with our old dish, nice white spun aluminum, feeder legs were hacked off and I doubt the motor works, I considered putting it up, but don't feel up to the challenge of modifying it, also could be warped, didn't do the string test, still have it and thinking of taking it to the scrap metal yard. The current owners had it pointing straight up and had planted flowers in it.
At 15 I didn't really know what money was, Mom paid around $ 2000 +, hard to believe someone paid $36,000 for one, guess cable TV wasn't available back then.
As for LNB'S I remember something about them being Cool or Hot, Anyone ???

 

[dragon002]

1985, isnt that when gore invented the internet??

 

[jayelem]

Well lets see if I can talk you into playing with it.

If it all sound like too much then give it a way in the classified forum. Spun aluminum make a nice dish when it comes to getting signal.

Well I like your encouragement, But no receiver, no feeder, no supports for feeder (very discouraging), at center of dish there is a cap and I have seen feeders mounted on a bracket that goes right to the center of dish, but like I said sounds like a modification that I'm not ready for, as for the dish, it is a beauty, and I know I should feel fortunate to have a solid dish 8.5 ft. I think.

I live in Chicago area, I possibly have a working c-band dish in summer thanks to a friend, even if it's mesh upgrading will be less expensive than putting the old one back up again.

 

[123tim]

Well lets see if I can talk you into playing with it.

Jaylem,
Nostalgia might make you regret shipping it to the scrap yard.