How do I know when I need to replace the LNBF?
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Some of the meters out there can drive the LNBF and give you a signal reading in the display which can tell you if it's working otherwise you have to check your receiver. But for the cost of either KU LNB or a C-Band LNBF I'd just buy a new one and if nothing else you'll have a spare. If what you have is really old then a new one could give you better performance and only replacing it will tell you.
unless you're losing channels why change it out?
I've had the same LNB on my setup for 6 years now....
I've had the same LNB on my setup for 6 years now....
Most often, reception problems are caused by things like corroded or badly installed fittings on the cable, not the LNBF itself. They have been known to go bad, but they get blamed for issues that are usually cable related.
I've lost several lnbs caused by lightning.
If you don't power off your equipment ,and a lightning storm is very close,,then you can lose a lnb from the static .
I'm only using KU's at the time.I have many on hand for replacements.
Also,the lower noise ratio,the better the signal (So I have read)
If you don't power off your equipment ,and a lightning storm is very close,,then you can lose a lnb from the static .
I'm only using KU's at the time.I have many on hand for replacements.
Also,the lower noise ratio,the better the signal (So I have read)
Test12345,
The best rule to remember is that LNBFs rarely fail. They are quite robust and it requires a lot of abuse to damage one either physically or electronically. A near hit or a direct hit from lightning will do it. Moisture entry that leads to corrosion damage or freezes inside can do it.
A frustrated installer with a 3 lb hammer can do it, too.
Typically the problem will be found to be with the cable connectors, the cables themselves, a switch or the dish alignment. Sometimes (and more frequently than we wish to acknowledge) even the receiver IRD. But, rarely does the LNBF itself create a problem. I have only had one fail in roughly ten years and that was a DN LNBF.
As for improving your reception and acquiring more channels, that is very doubtful. Unless you can prove that there is something defective with the currently installed LNBF, a new one or even a different style won't usually gain you anything noticeable in that regard. Not that it isn't a possibility, but it would be more akin to wishful thinking in most cases.
There can be lemons out there and the only way to prove it would be to replace it and compare the new results to the old. If you seem to gain or lose 1% to 5% signal quality, that isn't enough evidence to prove that one LNBF is better than another. An improvement of 5% - 10% might indicate something, but still not definite. An improvement of more than 10% begins to appear obvious.
Unless you have noticed a recent, dramatic change in your reception signal quality, there probably isn't anything wrong with the LNBF that you have and it may be more likely a cable or connection problem. If the signal degradation has slowly and continually been going downhill over a long time, it is probably a connection problem. Best thing you can do for your system is to get a small wire brush, about the size of a toothbrush and some good electrical grade contact solvent and clean up your connections (power the receiver down of course). Then apply some good electrical grade grease to seal out moisture. You might be surprised how much of a difference this will make if you have very old wiring outside in the elements. You might even consider cutting the old connector off and and stripping the line back a few inches and installing a new compression connector.
It is always good to dabble around and try new equipment, however. That's part of the hobby. I wouldn't go out and spend a lot of money, but you can buy very inexpensive LNBFs today and try many of them to compare.... BUT, you need to ensure that the cable and connectors are perfect first, otherwise you may obtain skewed and inaccurate results.
RADAR
The best rule to remember is that LNBFs rarely fail. They are quite robust and it requires a lot of abuse to damage one either physically or electronically. A near hit or a direct hit from lightning will do it. Moisture entry that leads to corrosion damage or freezes inside can do it.
A frustrated installer with a 3 lb hammer can do it, too.
Typically the problem will be found to be with the cable connectors, the cables themselves, a switch or the dish alignment. Sometimes (and more frequently than we wish to acknowledge) even the receiver IRD. But, rarely does the LNBF itself create a problem. I have only had one fail in roughly ten years and that was a DN LNBF.
As for improving your reception and acquiring more channels, that is very doubtful. Unless you can prove that there is something defective with the currently installed LNBF, a new one or even a different style won't usually gain you anything noticeable in that regard. Not that it isn't a possibility, but it would be more akin to wishful thinking in most cases.
There can be lemons out there and the only way to prove it would be to replace it and compare the new results to the old. If you seem to gain or lose 1% to 5% signal quality, that isn't enough evidence to prove that one LNBF is better than another. An improvement of 5% - 10% might indicate something, but still not definite. An improvement of more than 10% begins to appear obvious.
Unless you have noticed a recent, dramatic change in your reception signal quality, there probably isn't anything wrong with the LNBF that you have and it may be more likely a cable or connection problem. If the signal degradation has slowly and continually been going downhill over a long time, it is probably a connection problem. Best thing you can do for your system is to get a small wire brush, about the size of a toothbrush and some good electrical grade contact solvent and clean up your connections (power the receiver down of course). Then apply some good electrical grade grease to seal out moisture. You might be surprised how much of a difference this will make if you have very old wiring outside in the elements. You might even consider cutting the old connector off and and stripping the line back a few inches and installing a new compression connector.
It is always good to dabble around and try new equipment, however. That's part of the hobby. I wouldn't go out and spend a lot of money, but you can buy very inexpensive LNBFs today and try many of them to compare.... BUT, you need to ensure that the cable and connectors are perfect first, otherwise you may obtain skewed and inaccurate results.
RADAR
I would say it would not be a bad idea to change it, 10 years is a long time. Most importantly though I would consider changing the feedline. The RG6 can deteriorate over time, connectors can corrode, and it is also relatively inexpensive. Some older installations may be using RG59 which is more lossy and less robust than RG6, that should be changed out for sure. Most places that sell or install satellite equipment will have good quality cable available, you shouldn't have far to go to find some.
-C.
-C.
The most common reason to replace a working LNBF is due to frequency drift. As a DRO LNB(f) ages or is exposed to temperature extremes the LO frequency may start to shift. The receiver has an automatic frequency control circuit that can compensate for some amount of drift. As the LO drifts further from the target frequency, the receiver may take longer to lock and display a channel or eventually no longer be able to tune the channel if the LO has drifted too far.
To determine if the LNB LO has drifted and if so, how much, erase all transponders for a satellite and perform a Blind Scan. Compare the frequency of a specific scanned channel to "The List" or www.Lyngsat.com . If the channel's frequency is different on the receiver than the frequency posted, subtract the difference to determine how many MHz the LNB has drifted. If a LNB has drifted more than 3MHz it is a candidate for replacement.
Most receivers can typically auto tune a frequency drift up to 3MHz. We designed the GEOSATpro DVR and DSR models to compensate for +/- 8MHz.
To determine if the LNB LO has drifted and if so, how much, erase all transponders for a satellite and perform a Blind Scan. Compare the frequency of a specific scanned channel to "The List" or www.Lyngsat.com . If the channel's frequency is different on the receiver than the frequency posted, subtract the difference to determine how many MHz the LNB has drifted. If a LNB has drifted more than 3MHz it is a candidate for replacement.
Most receivers can typically auto tune a frequency drift up to 3MHz. We designed the GEOSATpro DVR and DSR models to compensate for +/- 8MHz.
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WOW!! Thanks for all the great info!!
SatelliteAV, I've always wondered why that happens (frequency shift), and now I know lol. Not good.
Can anyone recommend an LNBF? Definitely thinking about buying one. And also changing the wire and contacts now....
Edit: Just went outside to check my wires...how can I tell what kind of wire I have? It's unmarked, orange (looks like cable installers wire) and quite thin. I'm thinking it is indeed RG59 and not RG6.
SatelliteAV, I've always wondered why that happens (frequency shift), and now I know lol. Not good.
Can anyone recommend an LNBF? Definitely thinking about buying one. And also changing the wire and contacts now....
Edit: Just went outside to check my wires...how can I tell what kind of wire I have? It's unmarked, orange (looks like cable installers wire) and quite thin. I'm thinking it is indeed RG59 and not RG6.
Hi, I wanted to edit this but I dont know how...I've actually decided to make a separate thread with a bunch of questions, these included. So please ignore the above post!
Im in the process of replacing all of mine with Rg-11. Trying to talk them into some reminant feeder cable and ends. 2db loss would be really nice
Im in the process of replacing all of mine with Rg-11. Trying to talk them into some reminant feeder cable and ends. 2db loss would be really nice
RG-11 may not be necessary for most installations, but in my case I had to utilize it because my cable run was too long for RG-6 cable. I tried it first and I could not control the motor very well, the response was erratic and intermittent. I had too much line loss for that. I then bought a 1000 ft spool of RG-11 and compression connectors to match. It was a lot easier to work with than I expected and I am very pleased with the results.
If your cable run is less than 100 feet I doubt you will detect much difference between RG-6 and RG-11. But, for runs over 180 feet, it sure makes a difference that is easily detected.
I wouldn't recommend using RG-11 for short cable runs simply because of the higher price of the cable and connectors. It would be overkill and an added expense that isn't required or gainful.
I wanted to relocate my motorized dish so that I had a really exceptional LOS for the entire horizon and expressly for Hispasat @ 30W.
This meant positioning the dish farther from the house and away from the trees. The absolute shortest cable run (which wasn't a logical cable route) was too long for RG-6. I would estimate that at 160-175 feet. It was just barely acceptable.
I routed the RG-11 cable naturally and logically to the existing cable entry to the house and it performed fine. That run is about 280 feet, if I recall correctly. The RG-6 cable wouldn't suffice at this length (I tested it first before buying the RG-11).
My personal findings regarding the RG-6 cable length is pretty much in line with the general recommendations of the industry. However, not many engineers and installers mention the specific advantages regarding the use of RG-11 cable. I can attest to it's advantages first hand.
RADAR
I get all mine for free, installers commonly toss out reminant spools that have anywhere from 100 to 300 feet left on it, all direct burial rated. I keep a 1000ft spool on the service truck for installs but usually when the spool is done I have maybe 100ft or less on it that I save just in case. I install it enough and can see the difference in numbers using 6 or 11 on runs. Now if I had to buy it, I wouldnt but cant beat free
I do currently have a 60ft and 80ft piece that I havent found a use for yet
I do currently have a 60ft and 80ft piece that I havent found a use for yet
Myself the only one's I'm buying now are the BSC422 Dual C-Band manufactured by DMS International. And if you can't tell the cable type, just replace it. This may help as the Belden RG59 cable spool that I have is slightly smaller in diameter than RG6, has copper shielding and is a lot stiffer to bend.
sergei said:
Sergei,
Contact me if you want a sample to test and compare with a GEOSATpro C2. The C2 build is much heavier and with better performance. Your honest review would be appreciated!
FaT Air.. how long would the cable run has to be, before one can observe a noticeable difference in signal levels between RG-59 and RG-6, generally speaking? Thanks.
Replace with a good quality RG6 and there's no question what it is
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