[mythtv-users] Obama Recommends Delay in Digital TV Switch

[Brian Wood]

Jeff Walther wrote:
>> Date: Fri, 09 Jan 2009 08:54:31 -0700
>> From: Brian Wood <beww at beww.org>
>>
>> Allen Edwards wrote:
>>> Since this digital
>>> transition started we have been watching DTV.   The picture is great.
>>>  Switching back to analog I now find the signals have so much noise they
>>> are basically unwatchable.
> 
>> So in your particular case things got better. This will not be the case
>> for everyone.
> 
> Here in Austin, I can pick up the digital version of all the analog
> stations, plus three more new digital stations added by the original
> broadcasting stations (weather'y station; extra PBS--cooking all the time,
> it seems; and a cool retro station with old "Bold Ones" and "Suspense
> Theater" and such).
> 
> However, Fox and CW just drop out.   They have episodes where the digital
> converter box reports that there is no signal.   I can be going along
> watching (box says about 65% signal strength, whatever that means) and
> suddenly there's no signal.

Often the "signal strength" is actually the BER (Bit Error Rate) which
is somewhat related to signal strength, but not necessarily directly.

> 
> Off topic, I don't know whether this is switch-over pains for the two
> stations with problems (other four are fine) or whether I need to be
> looking at my equipment.   Maybe rotate the antenna a bit?   The fact that
> the signal indicator drops from good to 0, makes me doubt that the problem
> is on my end, but again, I don't know what that indicator is actually
> measuring.
> 
> The two problem stations appear to share a mast...

They may have to shut down when people are working on the mast, or
anywhere near it. When I worked at the WTC we had to shut down when
people were working in the antenna structure. We had to lock the
transmitters off, and give the keys to the WTC police. We were then held
hostage (usually in the CBS room) until we could power up again. Many a
card game was played during these "hostage" periods.

UHF transmitters tend to need more maintenance than VHF rigs. Some
stations do not yet have backup transmitters due to a lack of room, many
plan to install backup UHF rigs when they free up space by eliminating
the VHF analog transmitters.

beww