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Old July 18th 08, 04:30 AM posted to alt.tv.tech.hdtv,rec.radio.amateur.antenna
G-squared G-squared is offline
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First recorded activity by RadioBanter: Jul 2007
Posts: 7
Default True Outdoor HDTV yagi's

On Jul 17, 2:10*pm, "David" wrote:
wrote in message

...

(snip)
Usuaully its the stations the FCC did a screw-job on.
They already had
low-band analog and were given either a low-band
transition or a depricated
UHF transition in 52-69.


Congress should have mandated that the FCC find space on
high VHF or UHF for
all stations that wanted it, with an emphasis on making a
market have all on
UHF where possible, and where not possible, put many on
high VHF so that not
a single station is alone there.


Phil,

Some stations wanted to remain on the low VHF channels for
power and propagation reasons. Some broadcasters in the
Midwest with large coverage areas get a lower electric bill
on those channels even though the threat of interference is
higher. Interference is a bigger problem in metropolitan
areas than it is in the flat rural corn fields of the U.S.
bread basket.

David


I used to work at a low band VHF station that was running 56 kW ERP.
The actual transmitter output was 8kW visual and 2.3 kW aural. When I
bellyached that KABC 7 in LA would be running only 13kW DT, Alan
Figgatt pointed out that DTV doesn't require as much power as analog
and 13 kW should be good here. The point is that from a power
standpoint, VHF-lo vs VHF-hi wouldn't be all that big a deal. The
station gear and A/C would be a much bigger load than the actual
transmitter. Compare that to analog UHF where 55 kW visual and 10kW
aural is common. THOSE folks will see a big savings but compared to
the power load when all the studio lights are on for a production or
newcast, even 65 kW is a big part but not the biggest. HVAC can be a
bigger load issue - particularly with VHF-hi where 13kW ERP may only
need a few kW of acutal transmitter output.

I hope I don't hear how the DTV breaks up a lot during lightning
strikes. I know that on VHF-lo analog you get LOTS of 'sparklies'
during lightning storms.