Avionics News February 2021 - 52

THEORY & PRACTICE
Continued from page 51

transmitting information. Thus,
adapting FSK to Morse seemed a
logical thing to do. The " musical "
system of transmission didn't return
until the digital age, when one tone

52

avionics news

*

february

2021

would be used for a logic " 0, " and
the other tone would be used for a
logic " 1. " Bell Telephone brought
FSK back for its voice band digital
modem in 1962. The Bell system
worked at 300 baud and was full
duplex, meaning simultaneous
transmitting and receiving.

Today, there are almost
countless ways to send
information by radio, and we can
do so without huge antennas.
In our program at Pennsylvania
College of Technology, we
teach AM and FM, of course.
The students also learn about
FSK and phase shift keying. In
addition, students learn about
spread spectrum and multiplexing
techniques. Since VHF navigation
systems use a subcarrier to
transmit a reference signal,
students end up learning about
subcarriers, too. Since we have
students for only a limited time,
we don't have time to teach all
the details of various different
types of PSK and FSK. A quick
count of the modes available
within two popular software
systems for amateur radio digital
transmissions yields 154 possible
digital modes. Some, like radio
teletype, aren't so much different
from the Murgaš technique.
Measuring using today's
system, the baud rate for Murgaš'
transmission was approximately
37.35, and of course, Marconi's
system was even slower. The
original dial-up modems from the
1970s were 110 baud. Current
Wi-Fi sensors can reach speeds as
high as 921,600 baud. So Murgaš'
system was not very fast, but still,
the musical wireless telegraph
system was a breakthrough. I was
in contact with K3M using FT8,
a frequency shifting system using
eight closely spaced frequencies,
which take up a bandwidth of
50 Hz. Like Murgaš' system
and the Marconi radio telegraph
system, FT8 doesn't send a lot of
information in a short time. Instead,
it sends just enough information to
establish contact, and in my case,
earn a certificate. q


http://www.sandia.aero

Avionics News February 2021

Table of Contents for the Digital Edition of Avionics News February 2021

No label
Avionics News February 2021 - Intro
Avionics News February 2021 - No label
Avionics News February 2021 - Cover2
Avionics News February 2021 - 1
Avionics News February 2021 - 2
Avionics News February 2021 - 3
Avionics News February 2021 - 4
Avionics News February 2021 - 5
Avionics News February 2021 - 6
Avionics News February 2021 - 7
Avionics News February 2021 - 8
Avionics News February 2021 - 9
Avionics News February 2021 - 10
Avionics News February 2021 - 11
Avionics News February 2021 - 12
Avionics News February 2021 - 13
Avionics News February 2021 - 14
Avionics News February 2021 - 15
Avionics News February 2021 - 16
Avionics News February 2021 - 17
Avionics News February 2021 - 18
Avionics News February 2021 - 19
Avionics News February 2021 - 20
Avionics News February 2021 - 21
Avionics News February 2021 - 22
Avionics News February 2021 - 23
Avionics News February 2021 - 24
Avionics News February 2021 - 25
Avionics News February 2021 - 26
Avionics News February 2021 - 27
Avionics News February 2021 - 28
Avionics News February 2021 - 29
Avionics News February 2021 - 30
Avionics News February 2021 - 31
Avionics News February 2021 - 32
Avionics News February 2021 - 33
Avionics News February 2021 - 34
Avionics News February 2021 - 35
Avionics News February 2021 - 36
Avionics News February 2021 - 37
Avionics News February 2021 - 38
Avionics News February 2021 - 39
Avionics News February 2021 - 40
Avionics News February 2021 - 41
Avionics News February 2021 - 42
Avionics News February 2021 - 43
Avionics News February 2021 - 44
Avionics News February 2021 - 45
Avionics News February 2021 - 46
Avionics News February 2021 - 47
Avionics News February 2021 - 48
Avionics News February 2021 - 49
Avionics News February 2021 - 50
Avionics News February 2021 - 51
Avionics News February 2021 - 52
Avionics News February 2021 - 53
Avionics News February 2021 - 54
Avionics News February 2021 - 55
Avionics News February 2021 - 56
Avionics News February 2021 - 57
Avionics News February 2021 - 58
Avionics News February 2021 - 59
Avionics News February 2021 - 60
Avionics News February 2021 - 61
Avionics News February 2021 - 62
Avionics News February 2021 - 63
Avionics News February 2021 - 64
Avionics News February 2021 - 65
Avionics News February 2021 - 66
Avionics News February 2021 - 67
Avionics News February 2021 - 68
Avionics News February 2021 - 69
Avionics News February 2021 - 70
Avionics News February 2021 - 71
Avionics News February 2021 - 72
Avionics News February 2021 - Cover3
Avionics News February 2021 - Cover4
http://www.brightcopy.net/allen/avne/58-2
http://www.brightcopy.net/allen/avne/58-1
http://www.brightcopy.net/allen/avne/57-12
http://www.brightcopy.net/allen/avne/57-11
http://www.brightcopy.net/allen/avne/57-10
http://www.brightcopy.net/allen/avne/57-9
http://www.brightcopy.net/allen/avne/57-8
http://www.brightcopy.net/allen/avne/57-7
http://www.brightcopy.net/allen/avne/57-6
http://www.brightcopy.net/allen/avne/57-5
http://www.brightcopy.net/allen/avne/57-4
http://www.brightcopy.net/allen/avne/57-3
http://www.brightcopy.net/allen/avne/57-2
http://www.brightcopy.net/allen/avne/57-1
http://www.brightcopy.net/allen/avne/56-12
http://www.brightcopy.net/allen/avne/56-11
http://www.brightcopy.net/allen/avne/56-10
http://www.brightcopy.net/allen/avne/56-9
http://www.brightcopy.net/allen/avne/56-8
http://www.brightcopy.net/allen/avne/56-7
http://www.brightcopy.net/allen/avne/56-6
http://www.brightcopy.net/allen/avne/56-5
http://www.brightcopy.net/allen/avne/56-4
http://www.brightcopy.net/allen/avne/56-3
http://www.brightcopy.net/allen/avne/56-2
http://www.brightcopy.net/allen/avne/56-1
http://www.brightcopy.net/allen/avne/55-12
http://www.brightcopy.net/allen/avne/55-11
http://www.brightcopy.net/allen/avne/55-10
http://www.brightcopy.net/allen/avne/55-9
http://www.brightcopy.net/allen/avne/55-8
http://www.brightcopy.net/allen/avne/55-7
http://www.brightcopy.net/allen/avne/55-6
http://www.brightcopy.net/allen/avne/55-5
http://www.brightcopy.net/allen/avne/55-4
http://www.brightcopy.net/allen/avne/55-3
http://www.brightcopy.net/allen/avne/55-02
http://www.brightcopy.net/allen/avne/55-01
http://www.brightcopy.net/allen/avne/54-12
http://www.brightcopy.net/allen/avne/54-11
http://www.brightcopy.net/allen/avne/54-10
http://www.brightcopy.net/allen/avne/54-9
http://www.brightcopy.net/allen/avne/54-8
http://www.brightcopy.net/allen/avne/54-7
http://www.brightcopy.net/allen/avne/54-6
http://www.brightcopy.net/allen/avne/54-5
http://www.brightcopy.net/allen/avne/54-4
http://www.brightcopy.net/allen/avne/54-3
http://www.brightcopy.net/allen/avne/54-2
http://www.brightcopy.net/allen/avne/54-1
http://www.brightcopy.net/allen/avne/53-12
http://www.brightcopy.net/allen/avne/53-11
http://www.brightcopy.net/allen/avne/53-10
http://www.brightcopy.net/allen/avne/53-9
http://www.brightcopy.net/allen/avne/53-8
http://www.brightcopy.net/allen/avne/53-7
http://www.brightcopy.net/allen/avne/53-6
http://www.brightcopy.net/allen/avne/53-5
http://www.brightcopy.net/allen/avne/53-4
http://www.brightcopy.net/allen/avne/53-3
http://www.brightcopy.net/allen/avne/53-2
http://www.brightcopy.net/allen/avne/53-1
http://www.brightcopy.net/allen/avne/52-12
http://www.brightcopy.net/allen/avne/52-11
http://www.brightcopy.net/allen/avne/52-10
http://www.brightcopy.net/allen/avne/52-9
http://www.brightcopy.net/allen/avne/52-8
https://www.nxtbook.com/allen/avne/52-7
https://www.nxtbook.com/allen/avne/52-6
https://www.nxtbook.com/allen/avne/52-5
https://www.nxtbook.com/allen/avne/52-4
https://www.nxtbook.com/allen/avne/52-3
https://www.nxtbook.com/allen/avne/52-2
https://www.nxtbook.com/allen/avne/52-1
https://www.nxtbook.com/allen/avne/51-12
https://www.nxtbook.com/allen/avne/51-11
https://www.nxtbook.com/allen/avne/51-10
https://www.nxtbook.com/allen/avne/51-9
https://www.nxtbook.com/allen/avne/51-8
https://www.nxtbook.com/allen/avne/51-7
https://www.nxtbook.com/allen/avne/51-6
https://www.nxtbook.com/allen/avne/51-5
https://www.nxtbook.com/allen/avne/51-4
https://www.nxtbook.com/allen/avne/51-3
https://www.nxtbook.com/allen/avne/51-2
https://www.nxtbook.com/allen/avne/51-1
https://www.nxtbook.com/allen/avne/50-12
https://www.nxtbook.com/allen/avne/50-11
https://www.nxtbook.com/allen/avne/50-10
https://www.nxtbook.com/allen/avne/50-9
https://www.nxtbook.com/allen/avne/50-8
https://www.nxtbook.com/allen/avne/50-7
https://www.nxtbook.com/allen/avne/50-6
https://www.nxtbook.com/allen/avne/50-5
https://www.nxtbook.com/allen/avne/50-4
https://www.nxtbook.com/allen/avne/50-3
https://www.nxtbook.com/allen/avne/50-2
https://www.nxtbook.com/allen/avne/50-1
https://www.nxtbook.com/allen/avne/49-12
https://www.nxtbook.com/allen/avne/49-11
https://www.nxtbook.com/allen/avne/49-10
https://www.nxtbook.com/allen/avne/49-9
https://www.nxtbook.com/allen/avne/49-8
https://www.nxtbook.com/allen/avne/49-7
https://www.nxtbook.com/allen/avne/49-6
https://www.nxtbook.com/allen/avne/49-5
https://www.nxtbook.com/allen/avne/49-4
https://www.nxtbook.com/allen/avne/49-3
https://www.nxtbook.com/allen/avne/49-2
https://www.nxtbook.com/allen/avne/49-1
https://www.nxtbook.com/allen/avne/48-12
https://www.nxtbook.com/allen/avne/48-11
https://www.nxtbookmedia.com