[mythtv-users] OT - Antenna tuning/aiming

[Brad Fuller]

Brian Wood wrote:
> On Nov 2, 2006, at 3:33 PM, Brad Fuller wrote:
>
>   
>> Brian Wood wrote:
>>     
>>> On Nov 2, 2006, at 2:32 PM, Brad Fuller wrote:
>>>
>>>       
>>>>         
>>> I think azap and the like will give you a signal strength reading. I
>>> believe it gives you a BER as well, but I seem to recall reading that
>>> that particular card does not give meaningful BER information.
>>>
>>> Maximum signal strength may or may not equal best reception, because
>>> you might have reflections that can be minimized by turning the
>>> antenna slightly off peak. This is why the BER is a better indication
>>> of signal quality for digital signals, but I don't think you can read
>>> that directly from that card. Mine shows a zero BER no matter how bad
>>> the signal.
>>>
>>> (BER is the Bit Error Rate, in case you were not aware of that :-))
>>>
>>>       
>> Hey, thanks Brian. That works. Now I need someone to watch the numbers
>> while I twist!
>> (not that dance)
>>
>> Do you know why skew would matter on UHF?
>>     
>
>
> If the transmitting antenna was plane-polarized a skew adjustment  
> would allow you to exactly match the polarity with your receiving  
> antenna. Most transmitting antennas have "beam tilt" which can  
> distort the signal a bit. Even if the transmitter was circularly  
> polarized a skew adjustment might allow you to null out a reflection  
> a bit since reflecting usually distorts the polarity somewhat.
>
> Unless you are a fair ways from the transmitter I doubt that you  
> would actually see much difference though, but it might help in a  
> highly reflective urban environment like Manhattan. This effect would  
> be more noticeable on the higher channels.
. I'm near the santa cruz hills and most of the transmitters are in
pretty much the same direction but at different distances from me. The
farthest being about 45m the nearest about 16 miles. Here's the list.
(hope it comes thru ok.

Should I target a few of them to tune? How would you recommend the
procedure?


* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KKPX-DT 	65.1 	i 	SAN JOSE 	CA 	
	303° 	41.2 	41
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KGO-DT 	7.1 	ABC 	SAN FRANCISCO 	CA 	
	306° 	45.4 	24
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KPIX-DT 	5.1 	CBS 	SAN FRANCISCO 	CA 	
	306° 	45.4 	29
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KTSF-DT 	26.1 	IND 	SAN FRANCISCO 	CA 	
	303° 	41.2 	27
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KBWB-DT 	20.1 	IND 	SAN FRANCISCO 	CA 	
	306° 	45.4 	19
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KRON-DT 	4.1 	MNT 	SAN FRANCISCO 	CA 	
	306° 	45.4 	57
* 	yellow - vhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KNTV-DT 	11.1 	NBC 	SAN JOSE 	CA 	
	302° 	41.1 	12
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KMTP-DT 	33.1 	IND 	SAN FRANCISCO 	CA 	
	306° 	45.4 	33
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KQED-DT 	9.1 	PBS 	SAN FRANCISCO 	CA 	
	306° 	45.4 	30
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KDTV-DT 	14.1 	UNI 	SAN FRANCISCO 	CA 	
	355° 	17.6 	51
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KSTS-DT 	48.1 	TEL 	SAN JOSE 	CA 	
	355° 	17.6 	49
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KTEH-DT 	54.1 	PBS 	SAN JOSE 	CA 	
	356° 	16.8 	50
* 	yellow - uhf <http://antennaweb.org/aw/antenna.aspx?color=Y>
KICU-DT 	36.1 	IND 	SAN JOSE 	CA 	
	356° 	16.8 	52
* 	green - uhf <http://antennaweb.org/aw/antenna.aspx?color=G>
KTVU-DT 	2.1 	FOX 	OAKLAND 	CA 	
	306° 	45.4 	56
* 	green - uhf <http://antennaweb.org/aw/antenna.aspx?color=G>
KCSM-DT 	43.1 	PBS 	SAN MATEO 	CA 	
	306° 	45.4 	43
* 	green - uhf <http://antennaweb.org/aw/antenna.aspx?color=G>
KCNS-DT 	38.1 	SAH 	SAN FRANCISCO 	CA 	
	306° 	45.4 	39
* 	lt green - uhf <http://antennaweb.org/aw/antenna.aspx?color=g>
KSMS-DT 	31.1 	UNI 	MONTEREY 	CA 	
	132° 	16.4 	31
* 	red - uhf <http://antennaweb.org/aw/antenna.aspx?color=R>
KFSF-DT 	66.1 	TFA 	VALLEJO 	CA 	
	306° 	45.4 	34
* 	red - uhf <http://antennaweb.org/aw/antenna.aspx?color=R>
KBCW-DT 	44.1 	CW 	SAN FRANCISCO 	CA 	
	306° 	45.4 	45
* 	violet - uhf <http://antennaweb.org/aw/antenna.aspx?color=V>
KTLN-DT 	47.1 	IND 	NOVATO 	CA 	
	315° 	72.1 	47
* 	violet - uhf <http://antennaweb.org/aw/antenna.aspx?color=V>
KTFK-DT 	64.1 	SAH 	STOCKTON 	CA 	
	346° 	43.7 	62