Cable TV amplifier suggestions

[Slickone]

My parents need a new cable amp. The radio shack one like this quit working after probably 8-10 years of use. Should I just get another like that, or spend money and get another? Amazon has many. Would the ones that cost more (but say around $50 or less) really make any difference?

There's a splitter where the line comes into the house, right behind the TV in the den. So one split goes to that TV a few feet away, and the other split runs through 100 foot of cable under the house to the back bedroom. The problem I was thinking about if I got one of the splitter/amp combo units, is wouldn't it feed too much signal to the TV in the den? They don't have gain controls that I see.

 

[Modelworks]

What I would use:
Amplifier $23 , installs outside with the splitter. run a cable run to it for power. The amps that power over the cable I really do not like as they can harm equipment if not installed correctly. This one keeps it all separate and is waterproof.
http://www.yourbroadbandstore.com/product.php?pid=712654


How good is the splitter ?
The splitters sold by radio shack and places like that are really crappy. One of the ways cable companies find people stealing cable is to look for leaks in the network, easy to find because people always use those crap splitters.



Splitter $2
http://www.yourbroadbandstore.com/product.php?pid=705507

Attenuator $2
http://www.yourbroadbandstore.com/product.php?pid=202325

The attenuator would go on the tv closest to the amp if the signal is too strong.

 

[Slickone]

Thanks a lot. Strange that amp says it's shielded, etc, but then says indoor use only. I'll be using in indoors anyway.

Is that 6dB attenuator enough, considering the amp is 10dB, and there will only be 3 ft of cable between the amp and that TV?

BTW is that splitter considered a "low loss" splitter?
And is it better than this one? It's made by Ideal and I bought at Home Depot a couple years ago to try to fix a problem were my comcast HSI would periodically go offline for awhile. It might have helped reduce the frequency some but didn't solve the problem. It's also split outside before it comes into the house. I asked about it here and was told to get two taps instead of two splitters. I wasn't sure what that meant or if it would do any good, so I never got one. Also someone said I need to get a low-loss splitter instead of the one I have. So if that splitter at yourbroadbandstore is better, I might pick one up for me too.

 

[Fallen Kell]

The attenuator should be fine even with a 10db amp after a split (a 2-way split will cause a 3-4db loss in signal, so another -6db attenuator will cover any remaining extra boost if there was any). Again, the attenuator is simply to correct the signal back to proper operating levels.

 

[Modelworks]

Thanks a lot. Strange that amp says it's shielded, etc, but then says indoor use only. I'll be using in indoors anyway.

Is that 6dB attenuator enough, considering the amp is 10dB, and there will only be 3 ft of cable between the amp and that TV?

6dB is enough. Tv tuners can work over a wide range of up to about 15dB before it causes interference issues. Cable is usually at about 10dB max for video so 10+10= 20dB - 6dB = 14dB so that is the correct one.

BTW is that splitter considered a "low loss" splitter?

Two things are important with splitters. Insertion loss and isolation. Insertion loss is how much signal you lose by running the cable through the splitter. The one I linked is loses 3.5dB signal, the ideal one loses 4dB so the one I linked is better.

The other thing is isolation. The one I linked is 120dB isolation. That means that the signal once split will be kept separate from the two connections by at least 120dB. This is important because it means that something on one connection will not interfere with something on the other connection. They both get the same signal quality, even if you short the other line.

A tap divides the signal into two or more connections like twisting together the ends of a wire. The ideal way for something like a home with a cable modem is to put a tap at the entrance and run that to the modem, then put all the tv on a splitter. That keeps the signal level high but has the downside that the cable running to the modem will effect anything else connected in the home, extend the cable to the modem and it effects the signal of everything . A splitter allows you to keep all the home wiring separate but cost some signal to do it.

You can attach a signal meter to cable lines and watch how much it changes , I have seen signals plummet by just adding 5ft of cable to a tap because doing it changed the impedance of the wiring and caused lots of loss.