Garganta La Profunda
It has been decades since the first shortwave listener, listening sleepily to his radio late at night, was puzzled awake by one of those mysterious transmissions, now commonly known as" numbers" or "spy" stations.
For some, the eerie, mechanical female voice that speaks strings of seemingly meaningless numbers, has become a nightly companion. Like the smile of an attractive woman across the barroom floor, the transmission beckons seductively but when approached, demurs. It is maddening.
These broadcasts can be found all over the shortwave bands. Like the smiling woman in the bar; they make no effort to hide themselves. Numbers stations have powerful transmitters. Turn your back for a minute, however, and they are gone, faded into the low lights and smoky atmosphere.
"I would say" says well-known numbers' authority
Havana Moon in his book, Uno, Dos, Cuatro "that for one not to hear this 'semi-bionic' femme is just about impossible. And she has been at it for at least a quarter of a century You'll have to admit that a quarter of a century is a long time in the life of a mystery..."
Slowly, ever so slowly, however, the Spanish speaking lady with the mechanical voice has been giving up her secrets. Back in 1984
Monitoring Times revealed for the first time that at least one of these stations was based in the United States. That transmitter, broadcasting four digit numbers in Spanish, was discovered in Warrenton, Virginia; (See also Monitoring Times May, 1988, "Utility World )
Now Monitoring Times reveals the location of yet another four digit Spanish language numbers station the state of Florida
The exact location of this 2100 UTC 4670 kHz number station is 26 degrees 56 minutes north and 80 degrees 5 minutes west just to the south of Jupiter Inlet An aerial examination of the site revealed three circular HF antennas forming a triangle.
Due to the methods used specific information on how this new numbers station was dis covered cannot be disclosed. However, rest assured that the disclosure comes from a very reliable highly placed source The information has been cross-checked and proven accurate and conclusive
A Federal Connection
A microwave receiving antenna was also noted transmissions in the 2 GHz range aimed at this antenna were monitored coming from a passive repeater to the south of Jupiter
Inlet. These transmissions were eventually traced further south to their source atop the Federal Building in Miami, Florida.
Transmissions on this microwave link appeared to be data that our MT source says is then decoded at the numbers station site and synthesised into the voice transmissions for broadcast.
This number station site reportedly is owned and leased to the federal government by RCA communications. RCA also owns and leases to the federal government the HF transmitter communication complex at Malabar, Florida, long believed to be another site for numbers transmissions.
The Spy Connection
In a related development, another anonymous source has forwarded to
MT an Italian-to-English translation of a very revealing interview concerning four-digit number transmissions.
In the interview which appeared in the October 10, 1987, issue of the respected Italian weekly. publication
Europeo, Mario Casagrande claimed to have spent twelve years working as a double agent loyal to Cuba and the United States.
Here is that portion of the interview concerning American numbers broadcast. MT readers will find this interview very enlightening as to the nature of four-digit spy number transmissions.

Q. How did the CIA remedy these difficulties with the microdot?
A- Raphael decided that I would receive radio messages. So, in the middle of August, 1979,1 returned to Mexico City for another training class on the use of the radio.
Q What were the transmissions like?
A. We agreed on two daily transmissions at 7 PM and 8 PM. This schedule coincided with my practice of spending a couple of hours working in my study just before dinner. The CIA was very concerned that I did nothing to alter my daily routine to encourage curiosity and suspicion. The message was transmitted in code on two different shortwave frequencies. The radio that I used was a Sony bought in an electronic appliance store in Panama, which the CIA suggested to me.
Q What kind of code system was used?
A. Every message was sent with the simulated female voice known to us as Cynthia from Langley. It began with ten minutes of identification, during which a series of three digit numbers was transmitted. If the middle
digit was even, it meant that a message would follow. When they didn't have anything to tell me, that digit would be odd. In this case, the message that followed was unintelligible. In any case the transmission took place every day.
Q. How did you decipher. it?
A. The message itself consisted of a series of four digit numbers, Normally there were no more than 250 numbers, the equivalent of three pages of a big pad of graph paper Once the numbers were transcribed I took a tiny pad full of numbers, that had been given to me by the CIA, to decipher the radio messages This also consisted of a seines of four digit numbers. There were about 3000 numbers, so that it could last for months and months of transmissions.
To decipher the message, I had to subtract the numbers received by the radio from those written on the tiny pad. The results were numbers between I and 26, equivalent to the number of letters of the English alphabet The number 1 corresponded to the letter A 2 to "B" and so on. This system is absolutely unbreakable by anyone without the tiny pad and every message is decipherable only by the pad of the agent to whom it is sent. In the case that the pad should fall into the hand of the enemy, it is possible to decipher messages for a limited period of time only
Q. What were the messages about?
A. They were requests for information, or operational messages, with which meetings in Havana were set up, or plans for trips abroad
Q. With what frequency were the messages sent?
A. Considering that I was often abroad, I think that in Cuba I was receiving about 35 messages each year,
Q. When you travelled, what happened.
A. Transmissions were sent on normal frequencies and therefore the CIA knew they were intercepted by the Cuban counterespionage To avoid any connection to my presence in Cuba during my trips they would interrupt the transmissions a few weeks earlier, or they would continue even when I wasn't there
There is no shortage of speculation as to the purpose of the numbers transmissions:
instructions for spies in the field (both theirs and ours), disinformation by the CIA, a HF back-up for the Washington-Moscow hot line (both: started at about the same time), international banking information, a beacon for extraterrestrials Or nothing.

Monitoring Times June 1988