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is there an inexpensive way to help align my antenna to distant sources.


i have a channelmaster 4248 that people say is VERY direction dependant. right now I'm leaning out the window and twisting the pole with the sound turned up to hear when i get a signal. am wondering if there is a channelmaster device which i plug in-line of the coax and it helps me tune in these channels.


also, what happens if I ALSO mount a 4228 bay-type antenna pointing a different direction. Are we sure i'm going to get multicast anomalies? what type of junction box do i have to purchase to join the 2 UHF signals together?


the only signal meter i have is on the accessdtv screen, and it doesn't generate a tone and isn't very helpful since it jumps around a lot.


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Jaymer...

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AccessDTV (antenna on digital input, Tivo on analog)

HTPC, P3 933 (still having DVD playing probs)

NEC LT150 (awesome)

Homemade Blackout cloth screen (from Joann's Fabrics, $6 per yard)
 

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To join them correctly you can buy a Channelmaster product called a Jointenna. Make sure that the desired channel(s) from the one antenna isn't too close to any of the desired channels on the other antenna. You can find the Jointenna here: www.starkelectronic.com


If you don't have a bandpass filter and just use a regular splitter/joiner, you will introduce a lot of multipath. Think about it, for a given frequency you'll have the signal from one direction and the signal from a different direction at somewhat different timing. This is a pretty surefire way to introduce multipath into your signal reception.


For the money you would spend on the Jointenna, you may wish to simply buy a rotator for your antenna.


Jim


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Let me get this straight, this show is hi-def and 5.1, but my local affiliate makes it crappy NTSC and mono?!
 

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I have had more success aiming antennas that have a lot of gain at the desired frequency. If you are trying to pick up UHF channels and use a UHF-only antenna with a moderate amount of gain, the signal-strength meter will usually do the job.


Second-generation set-top boxes do a better job with multipath and will often lock up on the strongest signal.


Samsung's SIR-T150 has a nice tri-state LED display that shows red when unlocked (or no signal), orange when trying to acquire a valid 8VSB signal, and green when there is sync lock and equalizer lock. Very, VERY helpful for aiming an antenna with no other signal strength indicators.


This LED - or variations on it - is mounted atop the circuit board of most DTV set-top boxes I have tested. It serves to tell a service tech when the tuner is working correctly. Why these other mnufacturers - Zenith, Princeton, Panasonic, Sony - don't bring this LED indicator out to the front panel is a complete mystery to me.


Stacking antennas is a bit of an art form, but in general you cannot have two antennas aimed in opposite directions feeding the same coax for the same reasons given above. Signals arriving out of phase will simply cancel themselves out.


If there were good coax switches for UHF operation (insertion loss of under 1 dB), then a coax switch would be the way to go. Some manufacturers (accessDTV, Hauppauge, Princeton) provide more than one antenna input. I wish all STB manufacturers would provide two antenna inputs for dual antennas.


KC
 
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