Terminology: "Five by Five" etc.

[brett]

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?

 

[RemoveB4Flght]

correct, the first number is signal strength and the second number is clarity

 

[pilotyip]

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

 

[brett]

Thanks for the quick response.

correct, the first number is signal strength and the second number is clarity

 

[Oakum_Boy]

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 is outdated, but is still used.

 

[Oakum_Boy]

The readability x strength is still used in HF comm. and not really "outdated".

 

[CoolSidePillow]

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.

 

[Razorback Flyer]

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

 

[Say Again Over]

Wow, lot's of smart pilots on this forum! :beer:

 

[Erlanger]

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.