colin McDonald writes:
> so these power house stations would set up on Mexican soil, right at the
> boarder?

Yes. That is exactly what they did.

> I suspect mexico didn't have any real laws surrounding communications and 
> so
> on back then, so the operators of those stations had more or less free 
> rain
> if they were on Mexican soil right?

I am not an expert, but as I understand it, there was
considerable bad blood between the Mexican and US governments of
the day so this was Mexico's way to "fix our wagon," as a matter
of speech. They got a wonderful spigot of money from the people
operating the huge stations and they really ticked off the US
government in the process so it was win win as far as the
Mexican government was concerned.

	If you were a Mexican company wanting to run a radio
station in Mexico, I am sure the rules were more normal.

> seems like a pretty slick way of promoting your own propiganda lol.
> Though I've always found it slightly interesting how much media broadcast
> stations are controlled by the government.  Power restrictions, direction
> restrictions, location restrictions and so on.
> there doesn't seem to be the pervasive all american capitalistic attitude
> when it comes to mass media and broadcasting when the government controls
> it.

	Yes. There are tons of rules but it is partly because
the public air waves are considered a finite resource like
fishing grounds or timber. Once a frequency is allocated to some
organization, that slice of spectrum is off the table for the
expected coverage area.

	Agencies such as our FCC or Industry Canada are
responsible to see to it that the largest number of broadcasters
get a chance to use the public air waves without interference
which will reduce their coverage area and or make their signal
less desirable to listen to or watch so there are all kinds of
purely technical specifications about power levels and, in the
case of AM, directional patterns.

	Did you know, for example, that in the days of analog
television, here, one of the most common violations that TV
stations got sited for was having the vertical sync pulse too
close to 100% modulation. It can be as close as 96%, but it
should not be more than that?

	You might say, "What a stupid and picky rule!" The
reason why that matters is that most analog TV's derive their
audio by mixing the video and audio carriers which were always
4.5 MHZ apart. If the full envelope of the wave form is too
close to 100%, there isn't enough video carrier to allow the TV
IF to deliver a saturated sound carrier to the detector. If you
have ever heard a loud buzz on a TV signal which was related to
a high-contrast picture, then you experienced what is called
"sync buzz." Some television sets are worse at this problem than
others, but too much sync modulation will make most TV's buzz
because the audio carrier appears to drop completely out during
lots of white in a picture. The sync pulse is blacker than the
darkest shade of black and white represents the weakest part of
the carrier which must never completely drop out.

	There are rules that say that broadcast stations need a
standby transmitter and backup power source and the list goes on
and on.We had a period of time in the twenties when broadcasters
could run as much power as they wanted and did not have to watch
their transmitter frequency all that closely and it was an
unmitigated disaster so those rules are basically there to get
as much bang as we can out of a limited resource.