[mythtv] Ticket #2087: Clean up NTSC cable frequency tables

Michael T. Dean mtdean at thirdcontact.com
Tue Jul 25 16:29:42 UTC 2006

On 07/25/06 11:51, Daniel Kristjansson wrote:

>On Tue, 2006-07-25 at 01:22 -0400, Michael T. Dean wrote:
>>If that's not changed, the table created by 
>>the "cablehigh0" definition is missing channels 93 and 94 (and those 
>>that exist are at the wrong frequencies).
>cablehigh should only include channels above 730Mhz in frequency, but the
>enumeration should match the tables...

730MHz?  Currently for standard it starts at channel 78, which has a 
center frequency of 549MHz.  Should it be modified (in 
scanwizardhelper.cpp) to "Cable 114+" and the cablehigh frequency table 
changed to start at channel 114 (center frequency of 735MHz)?  Or, 
should I continue to start at channel 78, but with a frequency of 549MHz 
(instead of 559MHz)?

Also, the comment in frequencytables.cpp shows ushrchigh and usirchigh 
starting at channel 67 (and the table labels the channels as 67+), but 
the frequencies used are 535750000 and 537000000, respectively, which 
are basically the carriers for channel 76.  For these, the 
_frequencyEnd  is appropriate for ending on channel 94 (as indicated by 
the comments), so it looks like a simple transposition of digits in 76.  
For this I think I should modify scanwizardhelper to label it "Cable ?RC 
76+" and fix the enumeration to start at 76.

However, if we want to start at 730MHz, we should use channel 114 (as 
with standard), which has a center frequency of 733.7866MHz and 
733.2625MHz for HRC and IRC, respectively.


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