View Full Version : Req: multiplex 100mb and DirecTV over cable coax?

06-21-2003, 07:37 PM
I know this was visited a while ago when (I think) BubbleLamp was doing some re-wiring. Well, I looked at the thread and obviously have forgotten something so I'm starting a new one.

I'd like to connect my DirecTV oval dish with LNBs A & B to the coax which was run through the house by the cable company. Would also like to connect my LAN which is running at 100 speed.

I have a DTiVo downstairs with a computer and router. Upstairs is another router and the location I'd like to put a non-TiVo receiver.

Are there hardware products which would allow the routers and DirecTV receivers to share the cable TV coax?

If so, who markets them? Which truly work?

If the LAN speed is limited by the type of coax already installed, what specific testing must be done? If the cable can only support 10 mbit, I'd rather know that before buying additional 100 mbit devices which the cable won't support.

I do NOT have a cable TV connection and don't plan to have one. The cable company installed a frequency blocker so only the cable modem will work. This leads me to believe there should be a significant amount of bandwidth available on the already-present wiring.

06-26-2003, 06:19 PM
The only ethernet that I've ever seen on coax is 10Base-2 (10Mbps). I have never seen 100Mbps networking on coax, certainly not shared with sat signals. In theroy, it's possible to do it, but I have never heard of it being done. You would have to modulate the 100Mbps data into a specific frequency band, one not being used by the satelite signals, and mix that onto the coax with a diplexor. Then do the reverse everywhere you want to connect a networking device up. I imagine that the device for this, if they do exist, are like stackers for satelite signals, somewhat rare and expensive.

You're probably better off using CAT-5 cable or 802.11 wireless stuff for data networking.

06-26-2003, 07:30 PM
Yeah, I'm fully expecting to have to juggle a frequency band.

Wireless doesn't work here because they used a lot of aluminum 2x4s. Even if it did, isn't wireless slow? I figured the link between the routers would be 10Mbps sharing hte same coax. Apparently, there are different classes of coax.

I've got a cat 5 cable installed right now but the way the floor boards were put in we had to go outside the building. The more I think about it, the more I'd rather remove that because it's a rental.

I'm convinced the best option is to build your own home and put a gutter behind the baseboards so cable work is easy.

06-30-2003, 05:30 PM
Current wireless is 54Mbps, the slightly older standard is 11Mbps. Not too bad. Have you actually tried to run wireless there? Aluminum 2x4s shouldn't cause a big problem, the frequency is high enough that it should be able to go between the 2x4s without issue. I'm sure range will be somewhat diminished, but it should work.

06-30-2003, 05:40 PM
I tried (it goes to) 11 a few months ago. Whatever I use has to go through the ceiling/floor or somehow bounce up a stairwell and down 2 hallways. 54 is pretty good. Is that a different frequency band?

To give an idea of the problems, 900 mHz phones won't work from the kitchen mounting wall to the door, a distance of about 40 feet but not a clear shot. Cell phones rarely work inside. All the wireless phones are now 2.4 GHz.

It's a royal pain in the keister.

54 Mbps, even if it was only half that due to environmental problems, would be great. I can't imagine the delays of trying to send multi-gig files like DV over 11...