[BC] Timing out the sign off procedures.

[Mark W Earle]

On Tue, 21 Feb 2006 19:01:03 -0500 "Phil Alexander"
<dynotherm at earthlink.net> writes:
> On 21 Feb 2006 at 15:35, Paul Smith W4KNX wrote:
> 
> > AM from an engineering standpoint has some magic and mystery to 
> it, and a
> > lot of history.  FM to me, is just plumbing.  DA's have always 
> facsinated
> > me.
> 

I still find one of the most intersting physical plants to be in Houston,
at Senior Road. 9 full power FM's, tower is.. 1800 or 1900 as I recall.
Each station has a "room", nicely done. KODA had two transmitters at 90
degrees, a 45 degree "corner" with a rack of stuff, etc. Halon
suppressant. You opened a door and went behind the transmitters to work
on things for the most part. 

The site was positive pressure, central security controller (8" floppy
drive and all) running the gates, doors, and card readers. Two
generators, if one failed, the central controller commanded everyone to
1/2 power and it would run on one generator. 

Plumbing/ combiner: one of the first "big" ones, 1db insertion loss. 1/4
wave section with a big crank on the ceiling. This was to adjust the beam
tilt of the antenna. Antenna had two feed lines, and you could patch
either "half" of the antenna if a failure occured. As I recall it was
done by Harris, but I could be wrong - it never required much attention,
was put in before my tenure. 

Each station (except one) had a single bay at 1000'. So quite a bit of
redundancy. KODA when I worked for them also had an Aux site on a
building top downtown (since decomissioned, as I undersand it - I no
longer working there). 

> Heh, heh. There is a reason the rules call it the STANDARD BROADCAST 
> band.
> 
> But, in fairness, some multi-user FM antenna systems are a bit more 
> than
> simple plumbing. (Although plumbing does predominate.)
> 
> The thing I like about DA's is they follow physical laws very 
> exactly.
> (Most of the time. <g> )
> 
> 
> Phil Alexander, CSRE, AMD
> Broadcast Engineering Services and Technology 
> (a Div. of Advanced Parts Corporation) 
> Ph. (317) 335-2065   FAX (317) 335-9037
> 


Mark 
KLTG 96.5  KLHB 98.3  KOUL 103.7  KMJR 105.5
wa2mct at juno.com    Corpus Christi, TX