I just realized that X E R F call is a pretty neat one, as most of them were
back then.
I guess mexico already had the X E prefix even in the 20's and 30's?
regards
Colin
----- Original Message -----
From: "Pat Byrne" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, January 24, 2011 2:43 PM
Subject: Re: Really Big Transmitters
> The NPR article mentioned that as parts broke down, they were
> replaced with what was available and power was lowered over time. I
> wonder if X E R F is still out there in a diminished way?
> Pat, K9JAUAt 03:28 PM 1/24/2011, you wrote:
>> I am not surprised. That is just a lot of power any way
>>you look at it.
>>
>> When XERF first came on in the thirties, the transmitter
>>tubes had to be specially ordered. The transmitter was
>>water-cooled. I wonder, back in the late sixties or seventies,
>>if when the US and Mexico negotiated a better broadcasting setup
>>for the AM band, they just turned down the screen voltage on
>>that monster and kept it loafing along on 50,000
>>Watts. Just think, that transmitter was designed to put out
>>500,000 watts all day long so it probably could do 50 K for the
>>next 75 years and just get a little dusty.
>>
>> Seriously, it was probably full of PCB oil and hard to
>>keep going so they probably just scrapped it and bought a modern
>>transmitter.
>>Pat Byrne writes:
>> > martin,
>> > I also heard on an old NPR broadcast that XERF would bring close
>> > flying birds out of the sky to their demise. And I believe, in their
>> > heyday there were a number of "super power" stations just across our
>> > southern border.
>> > Pat, K9JAUAt 12:00 PM 1/24/2011, you wrote:
>> > > I recently finished reading a book about one of the
>> > >biggest medical fraudsters in US history who snake-oiled his way
>> > >to riches during the 1930's in the United States and then from a
>> > >powerful AM radio station on the Mexican border. His name was
>> > >John R. Brinkley and he called himself a physician though he had
>> > >no valid medical degree.
>> > >
>> > > Most of the book is not directly radio-related, but
>> > >there is a brief description of Brinkley's Mexican boarder radio
>> > >station which later became XERF and I am sure some of you
>> > >remember the preachers selling all kinds of stuff that one could
>> > >hear after dark on XERF.
>> > >
>> > > XERF's transmitters were just across the river from Del
>> > >Rio, Texas and, at one time, were 500,000 Watts directional in
>> > >to the United States.
>> > >
>> > > People report that at night, the antenna towers arced
>> > >with green flashes. XERF leaked in to telephones in town, could
>> > >be heard on things that weren't even electronic such as bed
>> > >springs, and made the headlights of cars come on even when they
>> > >were supposed to be off as they drove around town.
>> > >
>> > > XERF transmitted on 735 KHZ in the mid thirties and many
>> > >of the radios were TRF or Tuned Radio Frequency receivers. These
>> > >were the predecessors of the superheterodyne radios we are more
>> > >familiar with. In a TRF radio, you have 1 or more tuned circuits
>> > >which you peak and tweak until they are centered on the
>> > >frequency of the radio station you want to listen to. There is
>> > >no IF, no conversion, no nothing; just tuned tank circuits of
>> > >sometimes dubious Q factor between the antenna and detector.
>> > >
>> > > If you ever had a crystal radio or have seen an old
>> > >radio from the early part of the last century, it was a TRF.
>> > >
>> > > In the 1930's, XERF had such a power-house signal at
>> > >night that people trying to listen to other radio stations in
>> > >other parts of the AM band suffered interference from Brinkley's
>> > >transmitter no matter where they tried to tune.
>> > >
>> > > It was a combination of tremendous AM transmitter power
>> > >coupled with basically poor quality receivers.
>> >
>> >
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