Hi All,
I was at work last night at my radio station job, was a little bored, and was watching mockup fake EAS videos on Youtube, and ran across this on Wikipedia:
Hi All,
I was at work last night at my radio station job, was a little bored, and was watching mockup fake EAS videos on Youtube, and ran across this on Wikipedia:
http://en.wikipedia.org/wiki/CONELRAD
CONELRAD, the now fossilized predecessor of the modern Emergency Alert System.
I like how they marked the old time radios back then to help listeners find the stations that would rely alerts.
From Wikipedia:
CONELRAD had a simple system for alerting the public and other "downstream" stations, consisting of a sequence of shutting the station off for five seconds, returning to the air for five seconds, again shutting down for five seconds, and then transmitting a tone for 15 seconds. Key stations would be alerted directly. All other broadcast stations would monitor a designated station in their area.
In the event of an emergency, all United States television and FM radio stations were required to stop broadcasting. Upon alert, most AM medium wave stations shut down. The stations that stayed on the air would transmit on either 640 or 1240 kHz. They would transmit for several minutes, and then go off the air and another station would take over on the same frequency in a "round robin" chain. This was to confuse enemy aircraft who might be navigating using Radio Direction Finding. By law, radio sets manufactured between 1953 and 1963 had these frequencies marked by the triangle-in-circle ("CD Mark") symbol of Civil Defense.[3]
Even amateur HAM radio had to abide by CONELRAD's overlord like jurisdiction.
If you are interested in more of this stuff, read the next article on The emergency broadcast system which was succeeded by The Emergency Alert System at the present era.
I know that on my station at least you can program a PAL script in SAM broadcaster to relay amber alerts over the internet.
As they say here in Baltimore,
Have a good one!
Geoff
If you guessed this one you get the $1,000,000 prize:
CONELRAD stands for
CONtrol of ELectronic RADiation
http://www.oldradio.com/current/bc_conel.htm
Even amateur HAM radio had to abide by CONELRAD's overlord like jurisdiction.
I recall articles in Popular Electronics and/or Radio Electronics with plans to build a CONELRAD monitor for use at ham stations. The device silently monitored the carrier of a local station and operated a relay if the carrier went off which could be wired to signal the amateur operator of an alert. I also recall the tests of this system.
Our school had "duck and cover" drills from about '53 to '55 but discontinued them for some reason (probably realized the futility of this). I believe WLW at 700 AM 50 kW and WHIO 1290 5 kW were primary stations nearby, perhaps because they operated near the frequencies and could be "pulled" on frequency if needed.
Our community was near Wright Field (name at the time) which was a primary target for enemy bombing and things were pretty tense during the Cold War.
Neil
Changing the frequency of a radio station sounds like a tall order, even today. Did these stations need a second set of transmitters and towers, or did they switch crystals and re-tune everything?
They indeed actually have to physically change the transmitters frequency, that's why they had 2 frequencies. one was for stations closer to 640 the other was for stations closer to 1240.
(this was an attempt to stop the transmitter failures)
Now, Big transmitters, Do NOT like to have their frequencies changed, and upon CONELRAD tests, many transmitters failed, and died.
Mostly due to the constant Cycling of on and off, which they were not designed to do.
I recall reading about an engineer talking about conelrad, and how when he would have to change the frequency on his transmitter for conelrad, the transmitters tubes would glow bright deep red, indicating that the TX did not like it.
What was the emergency system used by broadcasters between Conelrad (1951) and EAS/CAP (1997)? You can tell me that one, you get a pat on the back? (So far, no one has mentioned it.) Previous posts describe the process for broadcasters, but incorrectly name it. It used tones instead of carrier drops or the current quacking sound. It replaced Conelrad in 1963 and continued until 1997.
of the Emergency Broadcast System. This is only a test.....(Dual tone alert.......)
That would be the EBS. Emergency Broadcast System.
very close to EAS. Emergency Alert System.
During the EBS period I worked at several AM and FM stations, doing announcing and transmitter duties, but was only very vaguely aware of what a full-out EBS emergency would require.
I knew how to run a test and ran one if it was logged on my shift.
I knew there was a secret envelope pasted on the wall that should be opened in an emergency. There were codes in there that meant something important.
I'm not sure how I'd know there was an emergency or what to do after ripping open the envelope.
The managers either didn't take it seriously, or assumed that a radio professional had previously been trained. I guess I didn't take it seriously either, because I never asked.
Our school had "duck and cover" drills from about '53 to '55 but discontinued them for some reason (probably realized the futility of this).
I recall us having the "duck and cover" drills in grade school, but with me it had to be somewhere around '67 to '69. About once a month a certain sounding siren would go off and all the students would immediately have to stop what we were doing and get under our desk and cover our heads with our arms. - That way we knew we would be safe in the event of a nuclear bomb falling on our school.
Anybody remember the "Cuban Missile Crisis"; when Castro was importing Soviet nuclear missiles and building launch sites within range of major American cities? Our parents were building fallout shelters and getting civil defense training at the local high school or wherever. To put an edge on the situation, Nikita Khrushchev was pounding his shoe on the desk at the U.N. to get attention.
I recall printed articles about fallout shelters and the advice to have a shotgun available to "protect your food supply" after an attack. I know of no one in our community who built a shelter but perhaps they followed the advice "don't tell anyone about your shelter".
We didn't have air raid sirens and the school personnel did not monitor broadcasts for Conelrad alerts. I suppose a flash was considered the alert.
I was in my first year of college when the Cuban Missile crisis happened and was so busy with studies that I failed to realize how serious this was. I don't know what I would have done differently had I known the threat so not having to deal with the anxiety was an advantage.
Neil
What you don't know can't hurt you till it does.
What you don't know can't hurt you
til it does. That's good.
In 1962 they started having drills in
our elementary school. They put us
all in the basement. We had no idea
what was going on. I have heard that
Hartford, CT (3 miles away) was
a major target - the U.S.S.R. had two
nuclear devices ready to hit there 24
hours a day. Connecticut was a big
target because of all the aerospace
companies around there. Also, the
submarine base in New London was
targeted. And in those days, Hartford
was known as the Insurance City, or
the Insurance Capital Or The World.
(For whatever that's worth.)
In the James Bond movie Goldfinger,
Aurick Goldfinger (the bad guy)
mentions to James
Bond that the submarine pens in
New London, Connecticut would be
a worthy nuclear target. Goldfinger
came out in 1963? It was the first
time I ever saw a Ford Mustang.
Also, the Goldfinger opening theme
was said to be the first movie music
ever composed specifically about the
villain. This had apparently never been
done before.
My 1962 Heathkit CR-1 crystal radio (which
was marketed as a bomb shelter radio)
has the Conelrad markings on it for
640 and 1240. I remember my dad
showing me the symbols for Conelrad
on the radio when I was 7 years old.
I had no idea what he was talking about.
In our town of West Hartford, there are
some bomb shelters in the wealthier
areas.
I remember reading in a blog somewhere
about an RF engineer who was in charge
of a daytimer on 1550 kHz. This guy said
it was VERY difficult putting his transmitter
onto 1240 to test it for Conelrad. He said
it took hours to get it right.
Interesting Stuff.
Best Wishes,
Bruce, MICRO1690/1700