5 by 5!!!

STS-41B

Well-Known Member
#1
What is it with this 5x5 everyone is uses lately? I realize it’s been around since WW2, the big one..
But.. until a few years ago, if someone wanted to know how they were coming across on the radio, it was “loud and clear.” Now it’s always 5x5 or 3x5 or whatever.
 

jynxyjoe

The Kickin' Chicken!
#7
What is it with this 5x5 everyone is uses lately? I realize it’s been around since WW2, the big one..
But.. until a few years ago, if someone wanted to know how they were coming across on the radio, it was “loud and clear.” Now it’s always 5x5 or 3x5 or whatever.
In case anyone didn't get that deep cut meta reference, you're loud but not quite clear.
 

GypsyPilot

Well-Known Member
#8
What is it with this 5x5 everyone is uses lately? I realize it’s been around since WW2, the big one..
But.. until a few years ago, if someone wanted to know how they were coming across on the radio, it was “loud and clear.” Now it’s always 5x5 or 3x5 or whatever.
I’ve been hearing it since I learned to fly 15 years ago.
 

LostComm

Well-Known Member
#11
I was a comm guy in the military for a while - a lot of the older equipment had a signal meter with 5 lights (horizontally) and 5 lights for volume (or squelch or something archaic). So 5 x 5 would theoretically be the best - except it wasn't. You generally wanted 4 x 5 because you never knew when your input was going to fry the receiver if your input signal was at 5 lights, so you'd turn the antenna away or otherwise attenuate the signal until you got a 4, maybe flickering to a 5 so you had a chance to catch a high powered amplifier that might fry your gear. (yes, occasionally some guy would do something that would put out waay too much power, like wire in the vehicle battery directly, or bring a linear amplifier to the field. Typically it would work for a short time, then burn out the transmitter or if we were lucky just the fuses.)
-LC
 
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Flyinthrew

Well-Known Member
#13
It is standard ICAO radio check readability scale.
1 – unreadable – bad
2 – now & then – poor
3 – with difficulty – fair
4 – readable – good
5 – perfect – excellent

Refer to ICAO Doc 9432, table 12.
https://skybrary.aero/bookshelf/books/249.pdf
I started using it when I first heard it over the Arabian Gulf. It is brief and intuitive. The antithesis of 75% of what we are forced to listen to on VHF radios in America.
 

erice

Well-Known Member
#15
Signal strength and readability. So 5x5 would be “loud and clear.” 1x5 would be very weak but clear. 5x1 would be a strong signal but distorted to the point of unreadable.
Technically, I think the order is readability, followed by signal strength. From my ham radio days, we used to give signal reports for Morse code at RST: Readability, Signal Strength, and Tone. For voice, it was only the first two (readability and signal strength).
 

jynxyjoe

The Kickin' Chicken!
#17
How would you put into words something like 3x5, or 5x2. "Well you're coming in strong but I can barely make out what you're saying."
I mean, radio full of static and Boston Center clearly going on about something behind the static? "Loud but unreadable Boston, havr you got another transmitter, all ive got is static and something about traffic below me." 5x2

Or" Boston understand you want descent now to F250, do you have another transmitter that's coming in barely above a whisper." 3x5
 

msmspilot

Well-Known Member
#18
Technically, I think the order is readability, followed by signal strength. From my ham radio days, we used to give signal reports for Morse code at RST: Readability, Signal Strength, and Tone. For voice, it was only the first two (readability and signal strength).
My bad. I looked online to verify I remembered correctly, and apparently got a bad source. Although I wish we could get pilots to quit using it altogether.

"Delta* 1*23, How do you hear this transmitter?" (With constant static the whole time, and volume low) "5x5"

yeah. whatever.

*Not picking on Delta. I've heard almost everyone do this. Just the first one that popped into my head.
 
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