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Terminology: "Five by Five" etc.

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brett

An office with a view
Joined
Dec 3, 2001
Posts
84
When rating a reception on the, "five by five" scale what do the numbers correspond to? I've never heard but assumed it is related to, "loud and clear" so the first number is how loud and second number how clear -- is this correct?
 
Goes back to WWI when voice Comm was first being used. It was to establish the ability to communicate clarity and strength. 5, being pronounced "fiveee", being the best. Words back then had to be two syllables with hard vowels, words like "Bingo", and "Popeye"; they were easy to ear and had specific meanings
 
Everyone should be using language advising "Readability X" where 'X' is a number 1-5 taken from the below table:

Readability Meaning
1 Unreadable
2 Readable now and then
3 Readable but with difficulty
4 Readable
5 Perfectly Readable

The 5x5 5x1, etc. is outdated, but is still used.
 
The readability x strength is still used in HF comm. and not really "outdated".
 
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I had learned that back when radios had to be fine tuned and the frequency strength was displayed on an oscilloscope. When the strength was good the frequency wave went full scale top and full scale bottom. Those values were 5. So 5 by 5 meant good reception.
 
Goes back to WWI when voice Comm was first being used. It was to establish the ability to communicate clarity and strength. 5, being pronounced "fiveee", being the best. Words back then had to be two syllables with hard vowels, words like "Bingo", and "Popeye"; they were easy to ear and had specific meanings

Actually, its even older than that. Its called the RST code, and is still in use today by amateur radio operators, shortwave listeners, and apparently Aircraft HF radio operators.

Stands for Readability, Strength, and Tone. Tone is only used for morse code transmissions, and is the tone of the "note" used for producing "dits" and "dahs" in morse code (i.e. if you hold the key down, does it waver or stay on the same pitch?)

Reability is how clear or garbled is your transmission, on a scale of 1-5.

Strenth is how strong your signal is comming through, on a scale of 1-9.

So If you're "5 by 9" you're Clear & Loud. "5 by 5," means they can hear you clearly, but you're transmission is a little on the weak/soft side (or the controller, while trying to soud cool, doesn't know that the strength scale goes to nine.)

Here is a link to a wikipedia article that seems pretty accurate:

http://en.wikipedia.org/wiki/RST_code
 
Didn't they use three numbers at one time too? I believe they were for readability, signal strength and tone. i.e.: 5 by 5 by 5.
 
Are those numbers ("5 by 5") pulished anywhere for official ATC and pilot use with definitions? I prefer to use loud and clear...or not so clear....just describe what I hear.

While we're at it...can you pilots drop the "with you" when contacting an ATC facility. ATC knows you are "with them" by the mere fact they hear you transmitting. "With you" is totally redundant and waste of air time.
 
with you

Try not so clear out of the country, won't mean a thing, as long as you stay in the states you will be fine.
 
Are those numbers ("5 by 5") pulished anywhere for official ATC and pilot use with definitions? I prefer to use loud and clear...or not so clear....just describe what I hear.

I don't believe so. I think it originally started with Amateur (Ham) radio operators and CB'ers too and though pilots and ATC use that terminology, I don't believe it's official aviation lingo.
 
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Goes back to the earliest days of radio! Back then you had two gauges. You could see your carrier wave on one and your modulation on the other! If you were 5 by 5 you had good signal strength and modulation. The terms stuck when radio was introduced to airplanes, but is NOT proper phraseology for pilots OR ATC under FAA (AIM) recommended usage. I agree that you will hear ALL kinds of stuff outside the US especially South of the equator. ICAO is "cracking down" on improper phraseology by requiring controllers to pass a multi part test on aviation English that includes pronunciation. If you fail, you have to get retrained and pass or lose your job. Part of being a professional in this business is eliminating "slang" such as "with you" and "fish finder" from your radio usage. IMHO This would make a good thread if folks posted their pet peeves on amateurish radio use they have experienced! Affirmative?
 
Yeah, we need to crack down on this "with you" and "fish finder" slang. These terms waste incalculable amounts of precious air time. We can and should all be little automatrons and speak nothing but AIM recommended phraseology. In fact, that's ALL I use at work and at home. It was a little weird at first tucking my kids in and saying goodnight to my wife but they understand the importance of keeping communication short and professional.

Here’s the new song I sing to our children to put them to bed:

"Silence little infant, maintain silence. You're biological Father will purchase an nesomimus (Mockingbird). In the event the Nesomimus negative squawk, biological Father will purchase a finger ornament with diamond attachment..."

Seriously, when the airwaves are congested is one thing. But half the time away from the North East it's light and not a big problem.


...Flame away.
 
Yeah, we need to crack down on this "with you" and "fish finder" slang. These terms waste incalculable amounts of precious air time. We can and should all be little automatrons and speak nothing but AIM recommended phraseology. In fact, that's ALL I use at work and at home. It was a little weird at first tucking my kids in and saying goodnight to my wife but they understand the importance of keeping communication short and professional.

Here’s the new song I sing to our children to put them to bed:

"Silence little infant, maintain silence. You're biological Father will purchase an nesomimus (Mockingbird). In the event the Nesomimus negative squawk, biological Father will purchase a finger ornament with diamond attachment..."

Seriously, when the airwaves are congested is one thing. But half the time away from the North East it's light and not a big problem.


...Flame away.


AMEN!

We are who we are. It's the color that we add that makes this jub still fun. take that away and we are one step closer to being replaced by robots.
 

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