Can I use a Direct TV dish as the antenna for my Sirius receiver?

January 9, 2006 12:24 PM

Can I use a Direct TV dish as the antenna for my Sirius receiver?

So, I have Sirius and I get spotty reception at home. Their FAQ says I should have my antenna facing a Northwest direction. Now, of course I can run the cable across the house to the Northwest side, drill a hole to the outside, etc etc, problem solved.

However, it just so happens that I have an unused DirecTV dish already mounted on the Northwest side of the house, and it's already cabled through the house. It would save me a lot of work if I could just use this as my Sirius antenna.

Can I just splice together the cable running from the dish to the cable that needs to go into my Sirius receiver? I'm pretty sure they're just both copper inside.

FYI, I am not a DirecTV subscriber so the dish is at the moment unused.

For answerers who have seen neither a DirecTV dish nor a Sirius antenna but may be able to answer, here are what they look like:

The DirecTV dish:
http://prosatellitesupply.com/images/DirecTV_PHASE_3_DISH.jpg

The Sirius antenna:
http://www.directed.com/audio/sirius/images/acc_windowsill.jpg

posted by poppo to Technology (12 answers total)

Best answer: The DirecTV antenna, being a dish, is highly directional and is aimed at the DirecTV satellites. So first, you'd have to re-aim it at the Sirius satellite(s) for it to work. Then, the dish recieves the signal at the LNB, which is tuned to the specific fequencies that DirecTV uses, which probably don't intersect with those that Sirius uses. So no, odds are you can't use the DirecTV dish.
posted by zsazsa at 12:34 PM on January 9, 2006

Response by poster: Dammit, that sounds pretty authoritative, thank you. Now next question, Zsazsa. Could I take the Dish off the roof, but leave the cable running through the house, and splice the Sirius antenna to one end (outside), and splice the Sirius adapter into the other (inside at the receiver)?

Hopefully this is a yes, if they're just single copper lines
posted by poppo at 12:39 PM on January 9, 2006

Could I take the Dish off the roof, but leave the cable running through the house, and splice the Sirius antenna to one end (outside), and splice the Sirius adapter into the other (inside at the receiver)?

Yes, both the Sirius antenna and the DirecTV dish use standard 75 ohm RF coax cable. Depending on the installation you may have to terminate one end or the other with a new connector - but that isn't difficult.
posted by RichardP at 12:44 PM on January 9, 2006

Best answer: Sirius does use a different type of connector than the standard "F" type that DBS satellite TV use, so you'd have to attach new connectors onto the ends. To make things easier, it looks like Sirius sells a combiner/splitter that can put the Sirius signal on the standard RG-6 cable with F connectors that the DirecTV dish is hooked up with. If you want the possibility of using the dish in the future for TV, you'd definitely want to use that.
posted by zsazsa at 12:55 PM on January 9, 2006

Best answer: I'm sorry, my immediately preceeding answer was incorrect. A bit of poking arround indicates that most XM and Sirius equipment and antennas use 50 ohm RF coax cable. If you want to use the existing 75 ohm cable you'd probably need an appropriate impedance transformer.
posted by RichardP at 12:58 PM on January 9, 2006

Best answer: Why don't you switch to Dish Network? the Sirius channels are included.

Also, if you can, place your Sirius antenna on the roof, pointing straight up. Terk makes a nice rooftop antenna that does the trick. You can even clamp it to the existing DirecTV dish.

Sirius's "point North/East" stuff generally works, but I've found that "straight up" hs worked the best. This has been the case in several places in California and Nevada as well.
posted by drstein at 1:14 PM on January 9, 2006

Response by poster: Why don't you switch to Dish Network? the Sirius channels are included.

Only the Sirius music channels are included. I need Stern.
posted by poppo at 1:21 PM on January 9, 2006

Response by poster: (and also drstein: thanks for the other suggestion of pointing up, this could potentially save me some work)
posted by poppo at 1:23 PM on January 9, 2006

Response by poster: richardp: re: impedance transformer. i am an amateur. is this something i could actually do myself or is it really complicated? my skills include wirestripping, twisting wires together, electrical tape, and/or light soldering.

To me, ohm is something people say while they're meditating.
posted by poppo at 1:26 PM on January 9, 2006

Best answer: Off the top of my head I would say no, just because of antenna positioning. Unlike XM and Directv, Sirius does not use geostationary satellites - instead it uses elliptical orbits. Downside is that the orbital math is a lot harder to compute, upside is that the satellites are higher in the sky in the northern hemisphere (since all geostationary satellites are over the equator). Here's a great link describing exactly what is going on up there.
posted by true at 1:51 PM on January 9, 2006

"Only the Sirius music channels are included. I need Stern."

Oh! I did not know that. I thought they had bundled all of them.

Stern 100 & 101 aren't on the web stream either. Lucky for me, I have one of my Sirius units at work. I WISH I could get the antenna on the roof but no such luck. I have a window that looks directly North (I'm in the south SF Bay Area) and I get no signal with I point it that way, but when I point it as straight up as I can (next to the window) - it works pretty good for most of the day.

Good luck!
posted by drstein at 9:07 PM on January 9, 2006

Response by poster: Well everybody had a lot of good info, thanks!

I am going to just run the Sirius antenna straight up to the top of the house
posted by poppo at 8:22 AM on January 10, 2006