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Antenna question...
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Posted by: iNerd

Can I plug two antennas into the same antenna port? I ask because I get great signals on all the stations I want except one (ch 11.1), all but ch 11.1 come from SF (north) and ch 11.1 comes from SJ (south) so my directional anteanna doesn't pick it up. If I can just also plug in my little RCA directional antenna and point it sount all would be well...

Posted by: FlyingDiver

You'll need an antenna joiner to make it work right. According to the experts on the "HDTV in SFBay" Yahoo group (which I recommend you join), you need a "Channel Master Joiner model 0582". Do a web search to find a supplier, or check out the archives for the Yahoo group.

I'm in Almaden, and I pick up ch 11 off the back lobe of my Channel Master 4228. But I'm real close to that transmitter.

joe

Posted by: btwyx

quote:
Originally posted by iNerd
Can I plug two antennas into the same antenna port? I ask because I get great signals on all the stations I want except one (ch 11.1), all but ch 11.1 come from SF (north) and ch 11.1 comes from SJ (south) so my directional anteanna doesn't pick it up. If I can just also plug in my little RCA directional antenna and point it sount all would be well...

Yes, I do. I use a splitter/combiner from Rat Shack. This does reduce the signal a bit, so FlyingDiver's idea of a fancy combiner might help.

You may want to hold off on 11-1. Its multicast currently on 48-2 and its also trying to move the transmitter to the same mountain as KICU (and KTEH if they ever start DT broadcast). I never watch any NBC so I've more or less given up on that one.

Posted by: iNerd

Yah, I never watch it either but damnit, I want all the channels available :) I'll try 48 or waiting, thanks!

Posted by: Regina

I am going to buy a 2nd Siver Sensor, as some stations come in better when it's pointed North and others are better when it's pointed South. Can I just use a plain ol' diplexer to join the 2? Or do I need the special combiner?
Thanks in advance for any advice!

Posted by: feldon23

The 2 antennae will interfere and cancel each other out.

Posted by: GoodSpike

http://www.avsforum.com/avs-vb/show...035#post3704035

Posted by: Regina

Bummer..I guess I'll get a rotor. :^(
I have another ? though...If I have an antenna installed in the attic, and a coax cable run to my 5x8 multiswitch, then could I still use the silver sensor? Or would that interfere as well? Would I need a 3rd coax cable from my multiswitch to the HR10-250??
Sorry to be so dense, but I don't get this antenna stuff!
THANKS!

Posted by: dswallow

Regina, playing with multiple antennas is an art, not a science. Certainly there's science behind it, but getting it just right takes trial and error.

A lot depends on what stations exist in your area... if there's any distant ones that might readily interfere on the off chance they're picked up by the antenna inadvertently.

For example, the Winegard SquareShooter, in UHF frequencies has some of th best front-to-back gain ratio... meaning it picks up almost no signal from behind it. If your stations are 150 to 180 degrees in different directions, it *might* be possible to combine two of those antennas aimed in opposite directions and simply combine the signals with a splitter used in reverse. A lot depends on whether there'd be multipath on some channels picked up by the antenna pointed in the opposite direction, and if there are any distant signals that might be broadcasting enough that occasionally atmospheric conditions bring that signal to you inadvertently.

The general rule is experiment. You won't know until you try. Some people do have surprising good luck with two antennas aimed in different directions. Others only increase their problems. Every situation is different because every location is unique in some way.

Even some problems can be overcome through the judicious use of notch filters to ensure no interfering signal in one band comes from the other antenna.

Some antennas also have the ability to get a decent signal coming from the back; so the judicious choice of one of those could solve your problems without need 2 antennas at all.

Experiment. Experiment. Experiment. :)

Posted by: Regina

Doug, Feldon, thanks and thanks everyone. Good thing I have lots of spare time and disposable income! Hee!
..one more thing...Doug, can I use a normal diplexer, or do I need a special combiner for my "experiment" of 2 Silver Sensors? I only ask because I bought a couple diplexers at CC 29 days ago and need to return them if I can't use them.
edit: according to antennaweb, my stations' towers are pretty much either northeast or southwest. Like 2 fans or brooms shooting off from my house!
Too cool, huh? Maybe this will work!:rolleyes:

Posted by: dswallow

quote:
Originally posted by Regina
Doug, Feldon, thanks and thanks everyone. Good thing I have lots of spare time and disposable income! Hee!
..one more thing...Doug, can I use a normal diplexer, or do I need a special combiner for my "experiment" of 2 Silver Sensors? I only ask because I bought a couple diplexers at CC 29 days ago and need to return them if I can't use them.

A diplexer combines a satellite LNB signal with an antenna signal; they're different from a splitter. You need splitters for your experiment of combining 2 antennas.

This will give you some examples of what happens when you combine two Silver Sensor antennas, though this is geared more towards getting stations that are in roughly the same direction: http://www.hdtvprimer.com/ANTENNAS/silver.html

But even aimed in the same direction, you get some effects of gain from the rear, so sometimes you have unexpected benefits doing non-obvious things.

Posted by: Regina

Ok, back to CC tomorrow! I will see if they have some splitters. In the meantime I ordered that dual bowtie antenna from Radio Shack that I read about on this forum. It was only $14. I'll give it a shot.
Thanks for the link, Doug. You rock immensely!

Posted by: Regina

Update: I returned the diplexers and got a splitter and some coax cables. I also got a Terk (I know, Terk BAD!) antenna; it looks most like a silver sensor w/rabbit ears. I combined them and added an in-line amplifier and pointed one to the northeast and one to the southwest. Now I get consistently high signal strength from all the OTAs except Channel 4, WTTV. I had e-mailed them about this and they did say I am in a limbo area, where most people cannot get WTTV's digital channel. Oh, well, they are "working on it" and hopefully will have a higher powered station soon.
In the meantime I can get ABC, CBS, NBC, PBS, FOX & UPN. Pretty sweet!
Thanks for all the advice everyone...beginner's luck is a beautiful thing. Hee hee!:D :rolleyes:

Posted by: dswallow

quote:
Originally posted by Regina
Update: I returned the diplexers and got a splitter and some coax cables. I also got a Terk (I know, Terk BAD!) antenna; it looks most like a silver sensor w/rabbit ears. I combined them and added an in-line amplifier and pointed one to the northeast and one to the southwest. Now I get consistently high signal strength from all the OTAs except Channel 4, WTTV. I had e-mailed them about this and they did say I am in a limbo area, where most people cannot get WTTV's digital channel. Oh, well, they are "working on it" and hopefully will have a higher powered station soon.
In the meantime I can get ABC, CBS, NBC, PBS, FOX & UPN. Pretty sweet!
Thanks for all the advice everyone...beginner's luck is a beautiful thing. Hee hee!:D :rolleyes:

When we say Terk antennas are bad, we're usually referring to that silly dipole thing that clips on to the satellite dish. :) Glad you're functioning!

Posted by: Regina

Thanks buddy! I was half-teasing about Terk. I am using a Terk splitter and amplifier and both are working well. I like the antenna too.
Ok, now I am just waiting for WB (4) to get their high-powered self up and running! Hurry up, guys! Hee hee!