question about inline signal amplifiers

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montyphan

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Apr 8, 2005
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first post, so i hope this is the correct place.

i live in a new apartment building, built last year and pre-wired for directv. i recently upgraded to HDTV, but i can't get a signal from the 110 and 119 satellites. i believe it's due to the long cable runs -- from the roof of our five-story building, the cables run to the basement, then back up to our fourth-floor apartment. i would like to try an inline signal amplifier. do i need to install it in the basement, where the lines come in from the roof, or can i install it in my apartment? also, we have a 5x8 multiswitch in the basement of the building (the dish serves four other apartments) -- if i need to put the amplifier there, does it work with multiswitches?

for the record, i've had various technicians try to diagnose my problem, and none have fixed it so far, but no one had suggested an amplifier, either, which is why i'm wondering if it'd even work. thanks.
 
Yes, you can use an amp, you would want to put it as close to the LNB as possible (i.e. close to the dish, and after any switches), below is one for $11.

http://www.sadoun.com/Sat/Products/Pico-Macom/la2150d-950-2150MHz-Satellite-IF-Inline-Amplifier.html

Pic: http://www.sadoun.com/Sat/Products/Pico-Macom/Pico-Macom-pictures/La2150D0-Amplifier.JPG

OR for $8:
http://www.sadoun.com/Sat/Order/Switches/inline_amplifier.htm

Pic: http://www.sadoun.com/Sat/Products/Accessories/PET10-6022.jpg

And welcome to satelliteguys. :)
 
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damaged said:

thanks for the help. just because i wanted to try something right away, i got this amplifier from radio shack. the question i have is that the amplifier says "Power Pass DC 14-18 V 25-40 mA." i know very little about this stuff, but i'm wondering if the 13 volts that's supposed to pass through one of the lines would be affected by the amplifier at all. probably a stupid question, but had to ask.

also, i noticed that the label on the multiswitch says (and i'm going from memory, so i hope i don't screw this up) "13 V, 0 kHz," "13 V 22 kHz," "18 V, 0 kHz" and "18 V, 22 kHz." if i want to put amplifiers on the lines that apply to the 110 and 119 satellites, would those be the "0 kHz" or "22 kHz" lines?

thanks!
 
The 13v and 18v are used by the receiver to switch LNBs (if the range of that radio shack one is 14-18v it may not work, as it may block the 13v, or may operate irradically, and/or hot), when you turn channels to one that is on a different satellite, now, when it states that it passes the voltage, it means it does not change it in any way, it just passes (as in does not block it) it as if the amp was not there, an amp that did not pass those voltages would render the receiver unable to switch LNBs.

The amplifier will go between your receivers tuner and multiswitch, close to the switch, that label is only for when the LNBs are attached to the switch directly (and multi-dish setups), in your case, they are not, instead, you are cascading from a built-in switch (there is one in the dish already which already combined all the sats), so ignore that label, as all the sats are already on all outputs of that external switch, so if you are only using one coax to your apartment, then you only need to add the amp to that one (yours) at the switch, on your coax, between the switch and your receiver only, i.e. just at the start of the long run of coax closest to the signal origin (the dish).
 
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damaged said:
The 13v and 18v are used by the receiver to switch LNBs (if the range of that radio shack one is 14-18v it may not work, as it may block the 13v, or may operate irradically, and/or hot), when you turn channels to one that is on a different satellite, now, when it states that it passes the voltage, it means it does not change it in any way, it just passes (as in does not block it) it as if the amp was not there, an amp that did not pass those voltages would render the receiver unable to switch LNBs.

The amplifier will go between your receivers tuner and multiswitch, close to the switch, that label is only for when the LNBs are attached to the switch directly (and multi-dish setups), in your case, they are not, instead, you are cascading from a built-in switch (there is one in the dish already which already combined all the sats), so ignore that label, as all the sats are already on all outputs of that external switch, so if you are only using one coax to your apartment, then you only need to add the amp to that one (yours) at the switch, on your coax, between the switch and your receiver only, i.e. just at the start of the long run of coax closest to the signal origin (the dish).

thanks, damaged. i'll look for a different amplifier. but just to be sure i'm clear: the lines from the dish go into a built-in multiswitch. four lines go from there to the basement and into a 5x8 multiswitch. from there, two lines go from that switch into my apartment. so the amps should go in the basement, at the outputs of the 5x8 switch that lead to my apartment?

one other question: when they wired this building, they put a 3x4 multiswitch in each apartment. the two lines from the basement go into this switch. from there, two lines go into my living room receiver, and a third line goes to a bedroom receiver. i realize this causes a problem for the 110 and 119 signals; to get them on the living room TV, i need to bypass the 3x4 switch. but that means no directv in the bedroom. my (temporary) plan, assuming the amplifiers work, was to bypass the 3x4 switch when the bedroom tv wasn't being used, but use the switch when we wanted to use the bedroom tv. would that still work? thanks again. i appreciate all your help.
 
I doubt that amplification will solve your problem. The 119 signal power levels aren't appreciably weaker than are the 101 levels. You may have a dish aim problem, or a wiring problem, or a partial obstruction, or even an LNB problem.

There will be no operational problem using an inline amplifier that nominally operates on 14 to 18 volts DC. If an LNB sees about 15.5 volts or higher, it sources the evens, and if it sees less than that, it sources the odds. In fact, if you send 18 volts to one side of the LNB and no volts to the other, the 18 volts will drive the LNB's amplifiers and you will get the odds from the port that has no line voltage present.

You can put a 10dB inline amp right near the switch input. You should not put it near the dish. The dish puts out about -30dBm of signal strength. The inline amps are low-powered amps and typically develop unacceptably high 3rd Order Intermodulation Distortion if driven above about -20dBm. The one exception is a very expensive Spaun 10dB inline amp that probably retails for around $70. I have used that at the LNB when my wiring was going to be relatively inaccessible for a few hundred feet, and I didn't want anyone in the future to have to spend hours looking for a the preamp if it ever failed. The 22Khz inputs are for Sat B/C.

How long are your lines? You should be able to safely go over 300 feet in combined dish-to-switch-to-receiver length without inline amplification, and I have never had trouble at less than four hundred feet.
 
Is it possible that , seeing it's an aprtment complex, that they can only receive programming from the 101, the core programming ????
Therefore making his efforts wasted ?
I am hoping that is not the case, but the thought did cross my mind ...
also, is the dish used for this type of situation the same as we use on our houses ?
Is the dish a 1, 3, or 5 LNB dish ... that could go a long way to explaining his issues as well, I don't think it's an amplification issue.

Jimbo
 
AntAltMike said:
I doubt that amplification will solve your problem. The 119 signal power levels aren't appreciably weaker than are the 101 levels. You may have a dish aim problem, or a wiring problem, or a partial obstruction, or even an LNB problem.

There will be no operational problem using an inline amplifier that nominally operates on 14 to 18 volts DC. If an LNB sees about 15.5 volts or higher, it sources the evens, and if it sees less than that, it sources the odds. In fact, if you send 18 volts to one side of the LNB and no volts to the other, the 18 volts will drive the LNB's amplifiers and you will get the odds from the port that has no line voltage present.

You can put a 10dB inline amp right near the switch input. You should not put it near the dish. The dish puts out about -30dBm of signal strength. The inline amps are low-powered amps and typically develop unacceptably high 3rd Order Intermodulation Distortion if driven above about -20dBm. The one exception is a very expensive Spaun 10dB inline amp that probably retails for around $70. I have used that at the LNB when my wiring was going to be relatively inaccessible for a few hundred feet, and I didn't want anyone in the future to have to spend hours looking for a the preamp if it ever failed. The 22Khz inputs are for Sat B/C.

How long are your lines? You should be able to safely go over 300 feet in combined dish-to-switch-to-receiver length without inline amplification, and I have never had trouble at less than four hundred feet.

thanks. well, for the record, no, the amps didn't work. i'm at my wit's end here because i don't know what the problem is. i'd say the lines are roughly 100 feet from the roof to the basement, then maybe another 75 feet back up to our apartment. i live in a complex with three identical buildings, each with its own triple LNB dish. a neighbor in another building, who also lives on the fourth floor (same as us), gets his Sat B/C signals with no problem. i checked, and ours is wired the same as his. he's the only other person in the complex with HD through directv.

now, i had a guy from directv come out, and he checked the signal in our apartment, and he said it was low. he said (and i'm just quoting what he said, not really knowing what it means), "it's in the 30s, and it should be in the 50s or 60s." however, i had another guy come out who didn't really seem to know what he was doing, but he bypassed the 5x8 switch in the basement, connecting two of the lines from the dish to the two lines going to my apartment. when he did that, i got my HD channels. however, the rest of the building lost half their channels, so that's not a feasible solution.

i've had two technicians check the dish alignment, and both said that was fine. there are no obstructions. one guy was set to replace the LNBs, but then he thought he fixed the problem when he bypassed the switch. could the switch itself be bad? does that ever happen? if so, what switch would anyone recommend?

edit: for the record, i swapped my lines with another apartment's lines on the output of the 5x8 switch, but it didn't fix it. could the switch's inputs be bad?
 
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it was the multiswitch. i swapped out one from the other building with the one in our basement, and everything works. i appreciate everyone's help on this board.
 
montyphan said:
it was the multiswitch. i swapped out one from the other building with the one in our basement, and everything works. i appreciate everyone's help on this board.
So now everyone at the other building is having trouble ?
You swapped them out with a going bad (possibly) multiswitch.
Did you call D* to let them know they need to replace it ?

Jimbo
 
Jimbos said:
So now everyone at the other building is having trouble ?
You swapped them out with a going bad (possibly) multiswitch.
Did you call D* to let them know they need to replace it ?

Jimbo

i'm selfish, but not THAT selfish. :) the other building has only one apartment with directv. he was hooked to a multiswitch in case other people in the building also wanted directv. i simply connected his line directly to the dish output. the condo board is buying a replacement multiswitch for the other building.

honestly, i got fed up with calling directv. the one time i did, the guy came out and supposedly checked the dish, then checked my signal strength and proclaimed it was a wiring problem. but he could plainly see that i was using a 3x4 multiswitch for a multiroom direct setup that included an HDTV. if it's your job to do this stuff, shouldn't it be obvious that that's wrong? i got the strong feeling from the technicians who came out that it was easier for them to say they couldn't fix it than to possibly spend more in replacement parts than the visit was worth.
 
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