Need help with cable signal booster

My cable comes in through the wall on second floor, then I use a splitter to send one to the first floor (for 1 TV set), another to the second floor (for 2 TV sets), the the rest to my third floor with 5 sets plus cable internet. Now I use a Motorola Cable Broadband Drop Hdtv Amplifier on the third floor. Before the digital and HD signal, I used several Radio Shack signal boosters but I got rid all of them. Anyway, the booster output is splitted into five, one go directly to my cable box for the HD TV set and the other four for the rest including the internet connection. Problem started when I noticed the pixelated video that I recorded from the HVDVR box or even view directly on a few channels like FOX for example.
So, I changed the connection by first splitting the output from the booster into 2, one of which goes directly to the cable box and the rest through a splitter for the other four. The pixelation disappears but I think my internet connection suffers. I ordered another booster but not sure where to put it: right on the second floor where the main cable comes in or somewhere on my third floor which matter the most. The distances from the cable outlet on the third floor are: 25 feet to the cable box, 25 feet to the kitchen TV set, 30 feet to the one in the bathroom, 60 feet to my computer and about 100 feet to my living room set.
I did tried a single booster on the second floor but the signal was not strong enough to activate the cable box on the third floor.

Do they have the cheap cable signal meter?
I have a satellite meter but don't think it will work with the Comcast cable signal.

Any suggestions will be appreciated.
Tanasit

Every time you introduce a spitter into a line, it results in a 3 db signal loss. Try to keep the number of splitter to a minimum, and make sure they are digital capable splitters.

One thing you have to do when dealing with multiple splits in a cable line is amplify it at the demarcation point. However, the line that goes to your cable modem CANNOT be amplified...you'll eventually toast your cable modem.

In our house we have 3 cable lines. One to a HD PVR, one to a HD set top box, and one to our cable modem. All of these lines are using 1993 spec coax cable, so we have to use an amplifier to get proper signal levels on the PVR/STB.

There is a splitter at the demarcation point.
One line off of the splitter is for the cable modem and is an unamplified signal.
The other line off of the splitter goes to a cable signal amplifier provided for free by my cable company.
Two amplified lines come out of the signal amplifier for the HD devices.

As for your question; most cable companies provide the amplifiers for free, but a tech usually comes and installs them.

What cable are you using and how old is it? Old or cheap cables cause loss. Ditto for couplers and splitters.

Making long runs and using multiple splitters is asking for a bad signal. Try to minimize them. Every coupler and splitter can cause more signal loss and noise.

Oxidation is not your friend. If the stuff looks dull, clean it. Cleaning the cable ends and all the connections will not fix everything but it's a cheap fix and will at least make sure the connections are good. Try a spray electrical contact cleaner and be sure to let it dry for about 5 minutes before you put it back together. When you reconnect it all, make sure the connections are tight -- a little more than just finger tight helps if the cable is liable to be moved at all during vacuuming, etc.

When I wired my home, I brought all the phone and cable connections back to one central wiring spot. I initially tried using a series of Radio Shack splitters for the cable and began having signal strength problems, similar to the problems you described. I also tried a cheap amp with poor results.

Finally, I bit the bullet and ordered this Amplified 8-Way RF Splitter and I haven't had any problems since then. It's somewhat pricey, but I probably spent just as much trying out all the $20 "solutions" before that.

BTW: It's supposed to help of you use the terminators on any unused connections instead of just leaving them empty. I think it comes with some, but I'm not sure. If you buy this and need some, let me know, I have spares.

Any cable left open ended can cause loss. Good idea to put a terminator on the end of any open cable.

I second the idea that you should amplify the signal as soon as possible. If you put the amplifier where the signal is real weak you amplify the noise as well as the signal.
A splitter at the point where the cable first enters the house should feed a dedicated cable that goes to the cable modem. The other side of the splitter should go to a BIDIRECTIONAL cable amplifier with multiple outputs.

The cable boxes for Comcast use a very low frequency for sending data back to the cable company. Without this data you can not use pay per view and video on demand. Many cheap splitters (and amplifiers) do not pass the lower frequencies since they are outside the range needed for TV signal transmission.

The other thing to keep in mind is that too much amplification can be as bad as too little. Many cable boxes (and the newest TiVOs) have a way to display the signal strength. I use that to make sure the signal is the right level for each TiVO and TV. If it is too strong an extra splitter will drop it, as weould an in line attenuator.

Daniel

To complicate the matter I also have a satellite dish for oversea broadcast which wasn't plan when I built the house. I have my contruction crews lay the cables inside the wall throughout the house with the cable wall outlets in each room.

When the Comcast tech came in to install my modem, he noticed a couple splitters with only 5-900MHz, so he changed them to the 5-1000 MHz (digital range) ones. I used the terminator for all unused ends. Also when I make my own connector end, I usually scraped off the coating on the center pin until the bare copper shows. Any extra cable I needed I bought the best one I could find and it is the studio grade and has the transparent blue insulator. Also the connectors themselves, I found that the gold ones didn't do a good job so I bought the outdoor grade ones with pre-applied silicone and dual rubber o-ring.

As per the advices above, I will install the Motorola amp at the entrance on the second floor and another one on the third floor but have the cable straight through the modem. I will also use the connector cleaner as well as the DeoxIT.

Currently my connection download speed ( http://www.speakeasy.net/speedtest/ )from PA to NY is about 20 Mbps on the off peak hours and drop to around 12 on prime time. PA to WA is anywhere from 6 - 10 Mbps.

With the low quality amplifiers, I could not activate the Comcast cable box from my third floor so I had to connect the box on the second floor, activated it and brought it back to work on the third floor.

Thanks for all your advices.

:twothumbs:twothumbs for the above CPF members.
Tanasit

PS. DonShock thanks for the offer, but I have just enough.

tanasit said:

Do they have the cheap cable signal meter?

Click to expand...

You probably already have one built into the caboe box. Most boxes have a series of diagnostic screens available, including screens for signal strength and bit error rates. On SA boxes, you generally hodl down the SELECT button until the mail indicator starts flashing, then press thr INFO button (your mileage may vary depending on the box and OS). You can even obtain signal strength for many cable modems by going to thgeir internal status pages at 192.168.100.1 (not applicable to all modems).

The cable needs to be RG-6. If any of it is RG-59, throw it out and replace it with RG-6.