Amateur Extra: Using ASCII Code

Amateur Extra: Using ASCII Code

What is one advantage of using ASCII code for data communications?

A. It includes built in error correction features
B. It contains fewer information bits per character than any other code
C. It is possible to transmit both upper and lower case text
D. It uses one character as a shift code to send numeric and special characters

This is yet another one of those questions that I’m not sure why it’s on an amateur radio exam, really.  But, there it is.  Let’s examine the options and figure out which is the “one” advantage.

A. It includes built in error correction features? FALSE.  ASCII is just a numeric representation of letters/numbers/symbols and doesn’t have any such thing.

B. It contains fewer information bits per character than any other code.  FALSE again.  There are much more efficient methods for this.  ASCII has its roots in computers, not radio.  It’s designed for programming, not efficiency in transmission.

C.  It is possible to transmit both upper and lower case text.  TRUE.  Different case of letters have different ASCII codes.  i.e. “A” is 65 where “a” is 97.

D.  It uses one character as a shift code to send numeric and special characters.  FALSE.  Look up any ASCII table and its plain to see that every symbol, whether its punctuation, numbers, letters, etc. has its own distinct code.  There is no “shift” modifier.

The answer then, would be C.  It’s possible to transmit both upper and lower case text.

I know, I know.  Why is this really important to amateur radio?  I guess its important working digital modes and needing to know the details behind how a data stream is coded.  Beyond that, its superficial knowledge.

But its on the test, and you should know the answer!

[E8D11]

(Image: https://commons.wikimedia.org/wiki/File:ASCII_full.svg)

No Comments

Post a Reply

%d bloggers like this: