[mythtv-users] Antenna and signal strength

[Yan Seiner]

Brian Wood wrote:

>On Feb 19, 2006, at 7:41 AM, Yan Seiner wrote:
>  
>
>
>You don't mention if you are trying to receive ntsc or atsc signals.  
>If the latter azap will show you the Bit Error Rate, which is more or  
>less directly related to the signal strength. I'm not aware of a  
>utility to measure analog signal level, but if all your signals are  
>coming form the same transmit site the aiming would be the same for  
>all of them.
>  
>

OK, I'll try azap...  As soon as my recordings stop...  Which could be a 
while.

>Your cable is probably RG-59 (75 ohm) and not Rg-58 (50-52 ohm).  
>There are some 50-ohm antennas made but they are not designed for  
>consumer  or normal TV reception use (not that it's a huge  
>difference, especially in an urban-grade signal contour).
>  
>
Yes.  the leg that's giving me trouble is RG-59U.  The other leg (on the 
other side of the splitter) is run in brand-new RG-6 and it has markedly 
better reception.

>You describe the antenna as a "yagi". I hope it is a modified yagi  
>design known as a "log-periodic". A true yagi has a very narrow  
>frequency range and is normally designed for a single channel, while  
>the log is a wide-band design intended to receive the entire VHF or  
>UHF band.
>  
>

It's one of those directional Yagi look-alikes:

http://www.kyes.com/antenna/antennatypes/uhfcorneryagi.gif


>Also, if this is a VHF-only antenna and you are trying to receive UHF  
>stations it may not work all that well. UHF stations are very  
>susceptible to multi-path and blockage so the mere fact that the  
>transmitters are close is no guarantee of good reception. NYC was one  
>of the earliest CATV markets due to poor reception even though 99% of  
>residents lived within 5 miles of the transmitters.
>  
>
The other way around, it's a UHF only antenna.  This could have 
something to do with the fact that I can't receive channel 7 at all, 
although it's local.

>Your use of the terms "RG-58" and "yagi" lead me to believe you may  
>be a ham ???
>  
>
No, not really.  I know enough about broadcast to be truly ignorant.  I 
am somewhat better aquainted with wireless networking, thus I know Yagi 
quite well.

>Lastly, remember the adage "You get what you pay for" :-)
>  
>
Well, I know.  But my SO (*S*he who must be *O*beyed) blew the budget on 
the TV and didn't think about all the other stuff needed to make it 
happen.  So we're trying to do this on the cheap.  Eventually I'll have 
to spend some $$$ on a Winegard and a nice amp to split the signal.... 
But for now, it's being done on the cheap, with a castaway antenna and 
some $3 passive splitters.

--Yan