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(Continued from page 1)Desktop vs. Laptop the inventors had to establish the bandwidth for a
broadcast television channel. Based on the video
Currently, only traditional 3.5” drives have very and audio information needed to be packed into the
large capacities available (4TB+), but as time goes signal, the decision was made to allocate 6 MHz to a
by, SSDs will become cheaper and a much better broadcast channel. So every television broadcast
alternative. Check out my journal article earlier this channel signal was designed to take up 6 MHz of
year where I compared the two for full details. Dis- bandwidth. Remember, that was in the prehistoric
play – This is an area where desktops can be a bet- days of Analog television signals. We are now in the
ter value for the flexibility to connect to whatever digital television age, as evidenced by the many nice
size display you have. Whether it is a 4K UHD 75” slim, large screen TVs around us. If you’ll remember,
panel or a 24” desk LCD panel, either will work on a this transition took place way back in 2009, June 12,
desktop. Now, many laptops offer HDMI or other 2009, to be exact. That was the day our old Televi-
ports to connect to displays, but if the reason for the sion sets could no longer bring us entertainment and
laptop is portability, then the size of the laptop information unless we acquired an analog to digital
screen is what you’ll be using most of the time, typi- converter box.
cally 13” to 17”. The larger the screen, the weight
will also increase proportionally on a laptop. The government even gave us the opportunity to
Graphics – Without a doubt, desktops are better purchase two of these devices for $35 each, in ad-
suited for gaming due to the flexibility to replace vance of the transition, so we could make the transi-
and upgrade the video card. Some laptops, such as tion and not miss a single television show. (I only
those from Alienware, do offer several video card had one TV at the time, so I only purchased one of
options to compete with the best desktop offerings, these devices, and believe it or not, I still have it. I
but these are limited and more costly. For non- used it for a while until I stepped into the digital tele-
gamers, the basic video in either laptops or desk- vision age. Anybody still need a converter box?)
tops is sufficient 95% of the time. Now we have digital television, but we still have the 6
MHz television channel bandwidth. The bandwidth of
In the December 2019 issue of Consumer Reports, a signal is related to the modulation scheme used to
there just happens to be an article about this very create the modulated signal. The modulated signal
topic. They report that in a survey taken in 2009, must fit within the bandwidth allocated, otherwise,
about 72% of the households have a desktop ver- the Federal Communications Commission (FCC) will
sus the 52% reporting having a laptop. Jump for- be very unhappy. (First, just a quick technical expla-
ward to 2019 and the number is now reversed with nation. Modulation is the process of putting a signal
more households reporting laptops than desktops in (video or audio) on a carrier frequency signal. The
almost the same ratio – about 74% laptops and carrier frequency signal (think WCTQ is on 96.3
52% desktops now. Check it out for their recom- MHz) is the frequency used to carry the signal from
mended models and other factors you may want to the transmitting antenna to the receiving antenna.
consider. Then at the receiving television set, the modulated
If you have suggestions for topics that you would signal is demodulated to recover the original signal.
like to see explained, please let me know! End of explanation.)

So when the transition to digital was being explored,
Cable or Air? – in the latter days of the last millennium and the early
days of this millennium, the broadcast industry and
What’s your choice? the cable TV industry had to decide what type of
modulation scheme to use with the new digital televi-
sion signals. (By the way, here’s a nearly useless
piece of trivia, the analog television modulation
By Phil Sorrentino, Contributing Writer, The Computer scheme was called Vestigial Sideband modulation.)
Club December 2019 When TV was invented there was only one industry,
www.scccomputerclub.org Philsorr (at) yahoo.com that was the broadcast industry, but now there two
ways of getting television signals to customers, over
Most TVs default to Cable, so if you get your TV the air, and over the cable. Due to the differences in
programming via a cable company like Spectrum or transmitting signals over the air and transmitting sig-
Frontier, you don’t have to answer this question. nals over a cable, the two industries decided on two
But if you want to get “broadcast TV,” you will have different modulation schemes. Here are two other
to select “air” when given the choice. (Your specific pieces of trivia. The Over the air signal is modulated
television may use the term “broadcast” or over the using an Eight Level Vestigial Sideband (8VSB)
air (OTA) instead of “air”.) Way back in the modulation technique and the cable signal is modu-
30’s/40’s when Television was being developed, (Continued on page 10)

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