do i need an amp?

[trekerQ]

I have antenna on my roof and the cable runs down the side of the house into the basement and then splits three way, one to the main floor, two to the second floor. i am getting good reception on the main floor but not getting all channels on the second floor.

Will an amp help my reception on second floor? Any suggestion is appreciated. thanks.

[Gold]

It's really hard to tell if an amp will help without trying one.
With three splitters, I would think it's a good idea.

For me, there is a local channel which is an Edge 1
When I hook up my amp for DXing, I loose this one local, but I enjoy the hobby, & this one channel does not mean a lot to me. I actually gain 4 others which are 2 Edge with my amp.

So you my gain or loose a channel or to...It's really hard to tell.

[satchick]

A mast-mount preamp should overcome the losses of the cable and splitter... Splitters generally add 3dB of loss per port so that's a substantial part of your signal, especially if it was weak to begin with.

A longer cable run to the second floor is probably the cause of a low signal condition.

[Terryl]

You can get an amplified splitter, it will compensate for the signal loss, every port adds 3 dB of loss to the overall system, so a 3 way split would be -9 dB on each port.

Example: input signal = -40 dBuv, signal at each port = -49 dBuv, then you have to add the coax loss at -8 dB per 100 feet of RG-6 coax, also any type of connection will add loss to the system, 2 connectors and a barrel connector will add 3 dB of loss.

So as Satchick mentioned a mast mounted pre-amp will compensate for the loss to the splitter, then an amplified splitter would work the best for long runs to the TV sets.

Note,-3 dB loss is 1/2 of the total RF voltage on the system.

[trekerQ]

It's really hard to tell if an amp will help without trying one.
With three splitters, I would think it's a good idea.

For me, there is a local channel which is an Edge 1
When I hook up my amp for DXing, I loose this one local, but I enjoy the hobby, & this one channel does not mean a lot to me. I actually gain 4 others which are 2 Edge with my amp.

So you my gain or loose a channel or to...It's really hard to tell.

Thanks for the information....it looks like i will need some sort of amp.

[Terryl]

Try the mast mounted one that Satchick mentioned, it will compensate for some of the line loss, if you do, be sure the splitter will pass DC on one side (the shortest run), and that side is were the power inserter goes to run the pre-amp.

Hint.......Install the pre-amp on the mast a couple of feet (or more) off the roof line so snow wont get to it, this also makes it easy to get to if you need to service it, also make sure the antenna and mast are grounded to a metal cold water pipe, or main outside electrical ground, it makes things work a bit better.

[trekerQ]

Try the mast mounted one that Satchick mentioned, it will compensate for some of the line loss, if you do, be sure the splitter will pass DC on one side (the shortest run), and that side is were the power inserter goes to run the pre-amp.

Hint.......Install the pre-amp on the mast a couple of feet (or more) off the roof line so snow wont get to it, this also makes it easy to get to if you need to service it, also make sure the antenna and mast are grounded to a metal cold water pipe, or main outside electrical ground, it makes things work a bit better.

Thanks for the tip! i been reading and know the basic between an amp vs pre amp. i have one problem with a pre amp, my antenna is mounted on the roof, which i cannot get to. Can anything be done with a pre amp outside, other then installing it on the mast? Or should look into an amp for inside the house?

[trekerQ]

A mast-mount preamp should overcome the losses of the cable and splitter... Splitters generally add 3dB of loss per port so that's a substantial part of your signal, especially if it was weak to begin with.

A longer cable run to the second floor is probably the cause of a low signal condition.

Thanks for the advice. i will have to explore my options, because a pre amp may not work if i cannot get to my antenna.

[Terryl]

You can mount the pre-amp anywhere you can reach the coax comming down from the antenna.

And yes you can use a stand alone amp, it should go right at the input to the splitter, or get a 4 way amplified splitter like this one.


http://www.amazon.com/gp/offer-listing/B000KPS3GS/ref=asc_df_B000KPS3GS1428262?ie=UTF8&condition=new&tag=pgmp-1587-95-20&creative=395165&creativeASIN=B000KPS3GS&linkCode=asm

[trekerQ]

Thank you Terryl, i will give it a shot.

[stnky1]

For a pre-amp the closer you can get it to the antenna the better. The further away it is the more noise it passes along. Mine is mounted directly to my antenna mast with only 5 feet of cable in between the antenna and the pre-amp. You want it to push a clean signal to your TV rather than pull a noisy one. If you still need to add a distribution amp inside the house to make up for the splitter losses you can do that after.

[Terryl]

This may be true if your using cheap coax, the better the coax the less noise involved, also if you are using 300 ohm twin lead, that would pass a bunch of noise.

20 to 30 feet of good quad shielded coax going from the amp's input to the antenna would not introduce any amount of noise that could affect the system*.

There are pre-amps that can only be mounted directly at the antenna terminals, these type do a dual purpose, 1 is to change from the 300 ohm balanced antenna system output to a 75 ohm coaxial output, the second is the pre-amp.

One disadvantage on mounting the pre-amp at the antenna is if your pre-amp fails (and they do) you have to tear down the whole thing to get to it, unless its only 10 foot off the roof then its just tipy toes on a tall ladder.

*You all must remeber this is not like the old analog days where a noisy system will affect the picture, (snow in the picture) it's digital, it would take quite a bit of system noise to affect the picture.

[Terryl]

This may be true if your using cheap coax, the better the coax the less noise involved, also if you are using 300 ohm twin lead, that would pass a bunch of noise.

20 to 30 feet of good quad shielded coax going from the amp's input to the antenna would not introduce any amount of noise that could affect the system*.

There are pre-amps that can only be mounted directly at the antenna terminals, these type do a dual purpose, 1 is to change from the 300 ohm balanced antenna system output to a 75 ohm coaxial output, the second is the pre-amp.

One disadvantage on mounting the pre-amp at the antenna is if your pre-amp fails (and they do) you have to tear down the whole thing to get to it, unless its only 10 foot off the roof then its just tipy toes on a tall ladder.

*You all must remeber this is not like the old analog days where a noisy system will affect the picture, (snow in the picture) it's digital, it would take quite a bit of system noise to affect the picture.