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Bronze Star Contributor
Posts: 160
Registered: ‎06-30-2003

Cable Amplifier

Is there any advantage in adding a cable amplifier to the internet cable line? If so, where should it be installed? I have the line coming into the house split with a line to the TV and another to the cable modem.

I do not have digital TV. I have a Motorola SB5100 modem and recently upgraded to the $10 Speed option.

I have a Electroline EDA 2400 amplifier.


Any ideas appreciated.

Thanks,
Chat
Regular Problem Solver
Posts: 2,846
Registered: ‎11-02-2003

Re: Cable Amplifier

How much signal are you losing? As a general rule, "cable amplifiers" are prone to cause more problems than they solve.....If your up/downstream power levels and SNR look OK out of your modem (through any splitter(s) you may be running) you shouldn't need to use any kind of amp. If you're contemplating a long run of coax throughout your home, I'd do the run...THEN, if needed, check out a GOOD quality (ie., "commercial") amp; the added cost will most likely pay off in a quieter, more stable signal.
The skinny....Don't go with an amp unless you're "down to the last db"....;>)


Message was edited by: Dale
Message was edited by: Dale
Bronze Star Contributor
Posts: 160
Registered: ‎06-30-2003

Re: Cable Amplifier

Dale,

Thanks.
I have no problems with my internet service at all. I found the amplifier in a drawer and thought (herein lies the problem) it might help something.

My download/upload speeds are constantly in the 4000/350 range.

It is a case of believing the saying

"If it works, don't fix it"

ACTUALLY means

"If it is working, jump in, and tweak it until it doesn't work at all"

Chat
:smileyhappy:

p.s. I have no idea what a 'db' is, so I have no idea if I am down to my last one or up to my kazoo in them.
Regular Problem Solver
Posts: 2,846
Registered: ‎11-02-2003

Re: Cable Amplifier

You have no worries with 4000/350....
Right now (Sun. night, 1803L) I'm at 3522 down/351 up....
I'm OK with that......;>)
New Visitor
Posts: 2
Registered: ‎07-08-2004

Re: Cable Amplifier

How do I go about checking signal levels? What are acceptable levels? I'm using a Motorola SB5100 modem.
Thanks
Regular Problem Solver
Posts: 2,846
Registered: ‎11-02-2003

Re: Cable Amplifier

Go to: http://192.168.100.1
Click on SIGNAL......
Nominal values: DOWNstream power: 0 to-2dBmV
UPstream power: 40-50dBmV
SNR (signal-to noise): GREATER than 30dB
Normal "limits" are on the order of: 58dB UP
-15dB DOWN
SNR <25dB
With the SB series of modems, you're apt to find power levels, varying widely, will STILL allow the modem to sync and function...But if you find levels at the extreme edges, you should call Tech Support and find the root of the problem. I had a bad run of RG/6 coax; Comcast replaced it with new RG/11...Instantly gained 4-5dB of signal!
Bronze Star Contributor
Posts: 160
Registered: ‎06-30-2003

Re: Cable Amplifier

I ran the checks at the site mentioned - my results:

Downstream
Signal to Noise Ratio = 36DB
Power Level = -1dBmV

Upstream
power Level - 45 dBmV

Looks like I am perfectly normal :smileyhappy:
I can live with this
Bill
New Visitor
Posts: 1
Registered: ‎06-06-2004

Re: Cable Amplifier

Dale,

My modem is a 3Com 3CR29220 and I just checked my signal it says my Upstream Power is 56db and my downstream is -20db.

Seems way off from what you described earlier. I have no apparent problems with speed, but just kind of alarmed me.

Any thoughts, or should I call Comcast?
Message was edited by: Anon706198
Most Valued Poster
Posts: 1,233
Registered: ‎07-11-2004

Re: Cable Amplifier

http://www.dslreports.com/faq/3412
A good read for you.
Bronze Star Contributor
Donut417
Posts: 183
Registered: ‎03-21-2004

Re: Cable Amplifier

I have a 3com usrobotics modem and I cant check to see how my signal is doing. Any one know how on this modem?
Donut417
Regular Problem Solver
Posts: 2,846
Registered: ‎11-02-2003

Re: Cable Amplifier

Brian...
You can check for some more obvious problems, like loose/corroded connectors, frayed/broken cable, poor connection(s) at splitter(s); but 56dB Upstream is pushing the limit...at about 58 or so, your modem is likely to lose sync and do random reboots. If you haven't had a good tech check on your line in awhile, it'd be worth a call to get Comcast to roll a truck and do a complete signal check of your line, form the line amps to the pole drop, to your modem....Maybe you'll end up with a new line drop (RG/11 vs RG/6)and have your signal increase 3-5 dB overall like mine! Good luck!