Question About Coax (RG6) Lengths

[Loop 7]

I want to move a cable modem to another part of the house.

Modem is currently in one corner of the house and connected to a splitter (one RG6 cable to TV box / one RG6 to cable modem).

Via the crawl space which has already been rigged with cable supports to keep wires off the ground, I am planning to run a ~50 ft RG6 cable from that splitter to another part of the house.

There seem to be varying opinions online as to signal strength/loss when extending like this. A few claim the sky will fall and it's a recipe for disaster but others say it will be completely fine.

Any experiences or guidance will be appreciated.

[donh50]

You should only lose about 3 dB or so at 1 GHz and the modem band is usually much lower so less loss. Should be fine though depends also on the signal level and run from your house to the pole and nearest amp/repeater in the cable line (external to your house, usually on the pole). If you are paranoid you could use RG-11 or something like that instead but I really doubt you'll have problems.

We have several splitters cascaded and a pretty long run from the basement to the opposite corner two floors up to our cable modem and it is doing fine. I picked up a cheap cable amp (make sure you get one that has the reverse path for your modem!) and have had it in and out of the system without issue. Not even sure if it is in-line now, but that is another option if you have problems. My guess is you won't need one.

HTH - Don

[Casey Leedom]

Two comments:

1. Make sure the cable you picked up is solidly terminated. I bought some from Frys and the connectors pulled off with on;y a pound or two of force. Very annoying.

2. When I had ComCast come out to set up my connection after I put the new RG6 cables in place, the technician actually did a signal strength tuning for the cable and modem. So I think that even if you do have a small amount of attenuation, your provider can set things up correctly for the amount of attenuation. Heck, they may even be able to do it remotely if you call the service department.

Casey

[Loop 7]

Appreciate the information and advice.

Typical speed tests (ethernet via router) with the modem in current location are ~225 mbps down and ~17 mbps up. If we lost 20% of that, without noticeable latency drops, it would not be a problem.

Casey Leedom I'll check the terminators and also give the ISP a call if we have issues.

[donh50]

Transceivers include emphasis (equalization) to help better transmit and receive the signal. Additional loss does not usually mean a bandwidth reduction unless it is high enough to cause bit errors and resends in data transmission. You probably won;t see any change unless something is wrong (bad cable, bad connector, etc.)

[geeqner]

Make sure that the cable you are using is a modern, low-loss RG-6 "Quad" (usually has to do with the braid and foil)
I'll Second what Donh50 said - Most coax of that type attenuates about 4 dB per 100 feet
So, about half of that, plus loss for connectors
should be relatively insignificant

You can get compression-type F-Connectors at HD or Lowes, along with the tool for pressing them onto the coax