Title: TV tips
CITATION THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00084468/00001
 Material Information
Title: TV tips
Series Title: TV tips
Physical Description: Book
Creator: Pettis, A. M.
Publisher: Agricultural Extension Service
 Record Information
Bibliographic ID: UF00084468
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 221941411

Full Text






A. Pettis
A. M. Pettis


I/


-~---I I
































Fig. 1.-Rectangular living room plan showing possible locations for
TV sets. A, good; B, good if living room is wide enough for viewers to
be proper distance from set; C, poor because of light from windows; D,
poor because too close to heat of fireplace.


Fig. 2.-An L-shaped living room plan showing possible locations for
TV sets. A, good; B and C, poor (in front of windows); D, poor because
viewers cannot get far enough from set.







TV TIPS

A. M. PETTIS
Farm Electrification Specialist, Florida Agricultural Extension Service

CONTENTS
Page Page
How TV W orks ............................ 3 How to View TV ........................ 8
Florida Stations .......................... 4 Installation and Adjustment ...- 9
VHF and UHF ............................ 5 Controls ....................................... 10
Size ............................ ............. 5 Interference ........................... ... 10
K ind ................ ...................... .. 5 A ntennas ........................................ 11
Location .............- ..- ...-..... ........... 5 Repairs .......................................... 12
Lighting ....----- ...-...----.......--- 7 Safety First ............. ........... ..... 12

Rural families receiving television are privileged to have the
best entertainment and educational benefits ever made available
in the home. The wealthiest king a few years ago could not
buy that which many families enjoy today for a reasonable cost.
It has been said that television is the greatest influence toward
restoring family life as a group since the invention of the auto-
mobile helped to scatter the family.
This information has been prepared to help those Florida
rural families planning to obtain television sets or already en-
joying them. Television in the home is quite different from
radio in the home, and there are many new problems for the
owner to solve if he wants to get best results.
Some of these problems concern the installation and location
of the set and others concern proper lighting of the room for
television. Since TV is a new development and improvements
are constantly being made, it is difficult to prepare information
that will not be obsolete in a short time. However, these basic
suggestions should prove helpful for some time to come.

HOW TV WORKS
To understand how TV works it is necessary to know that the
human eye "remembers" what has been seen, even though the
picture is no longer there. Because of this effect, in movies the
eye "sees" a continuous moving scene, even though the scene
is really made up of many separate still scenes flashed by the
projector on the screen. Something similar to this occurs in TV.
The TV camera pointed toward a scene would divide this scene
into many small parts, and "look" at one small part at a time.
It sends a signal in proportion to the brightness of that part
of the scene. This procedure is continued at a speed so fast that
3







the small light and dark parts of 30 complete pictures are trans-
mitted every second.
For example, it is similar to reading a book. The human eye
does not see every word on a page at a glance. Instead it goes
from left to right, line by line, until each individual word on
the page has been read. The TV camera observes a scene in
much the same way and "looks" at each small part of the pic-
ture from left to right and from top to bottom.
The TV receiver picks up the signal just as it is sent from the
station. Every small part of a scene is put on the screen, one
at a time. This is done so fast the human eye seems to see a
complete scene that is constantly moving.

FLORIDA STATIONS
At present there are relatively few TV stations operating in
the state. Plans are underway for the construction of several
more stations that should be "on the air" in the near future.
The FCC (Federal Communications Commission) issues permits
and assigns channels to TV stations. This organization has
set aside, subject to possible revision, the following channels
for Florida cities:
City Channel
Belle Glade ........... ... -.....- ------ --------. 25
Bradenton -...... ..... ..- ..-...-...... .... .. 28


Clearw ater ...... ....... -. ..... .....
Daytona Beach ......-.... ................. .....--
D eLand ....... .......-- .. ..- ............ ....-
Ft. Lauderdale ........ -...... .................. ...
Fort M years ........ ............. ..- ...... ------ ... .
F ort P ierce ........... .-. ..--- ... ........... ... .....
Gainesville .......- ..- ... --------.....---------
Jacksonville ..... ... ..... ............ .. ..-
K ey W est .- ........... .... -. ------ ...
Lake City .......... -.. ............- .. ........ ......
Lakeland .- .. .-- ...................- ..
Lake W ales -......- ...-...-. ....-- ..... ......
Leesburg ........- ................
M arianna --....... ..... -... ----... ....-
M iam i ...... ..- ....-- ..- . .. - --. ------.. ....
O cala .........- ........ ...... .... -- ---- ... ....
Orlando ........-......... .......... -......... ..
P a la tk a --.-.-.---- ..- ...-- .- .......- ... .... ..-..-- - .-- ....-- ..-.. ...
Palatk a City ...... .. .. ...................................... ...
Panama City
Pensacola ....... -..... -- ......... ....
Q uincy .... .......- ... ...- ..-- .. .............. --
St. A ugustine ............................. ...............
St. Petersburg (See Tampa)
Sanford ............... ..................................
Sarasota ................ ....................... ... ........ ...
T allahassee ........... ......................... .........
Tampa-St. Petersburg .----.............. ..............
W est Palm Beach ......................... ..............
* Denotes stations originally planned as non-commercial,

4


44
17, 23
11
19
5*, 20
4, 7*, 12, 30, 36
14, 20
33
16, 22
14
26
17
2*, 4, 7, 10, 27, 33
15
6, 9, 18, 24*
17
7, 30*, 36
3, 15, 21*, 46
54
25

35
34
11*, 24, 51
3* 8, 13, 38
5, 12, 15*, 21
educational stations.






VHF AND UHF
VHF stands for very high frequency and refers to channels
2 through 13. UHF stands for ultra high frequency and refers
to channels 14 through 83. Practically all sets are designed to
receive all VHF channels. To receive UHF some manufacturers
make it possible to substitute UHF tuning strips for one or
more VHF channels.
On most sets it is possible to use a converter, either inside
or outside the cabinet, to convert the UHF signal to a VHF
signal. It will be necessary to tune both the converter and
the set.
Some sets have all-channel tuning built in. With all-channel
TV, you receive every new VHF or UHF station within range
as soon as it comes on the air. This type set usually costs more
than other types.
SIZE
A TV picture is 3/4 as high as it is wide. A screen size is
commonly referred to by its width. For example, a 17-inch
screen refers to one 17 inches wide. The larger the screen
the farther back a person should be to watch it. For the average
living room, a 16-inch to 21-inch screen should be satisfactory.

KIND OF SET
You would do well to buy your TV set from a local dealer who
has a repair department. The set should be a well-known make
that is guaranteed and that is approved by the UL (Under-
writers Laboratories).
Console and Table Models.-Whether to buy a console model
or a table model will depend on the individual family. Many
console TV models also feature radio and a record-player. In
general, console models are more expensive but usually have
better tone in the sound system. If a console model is obtained,
it is best to get a type that does not use any of the television
set parts in the operation of other features, such as a radio or
record-player. This is because television set repairs usually
cost much more than radio or record-player repairs. So it
probably would be poor economy to use parts of the TV receiver
to operate a radio, a record-player, or other device in the con-
sole model.
LOCATION
The location of the set in the room is a very important con-
sideration (see Figures 1 and 2). Unlike radio sets which may
5






usually be placed anywhere along the wall, a TV set will prob-
ably have only one or two desirable locations in a room. De-
sirable and less desirable locations are diagrammed in Figs. 1
and 2. Once you decide on a location, do not move the set about
the room the way some furniture is moved.
In general, do not locate a set so that a bright light, such as a
window, is behind it or on either side close to it. If you locate
a set close to such a light, the eye will adjust itself to this light
and the picture on the screen will seem dark. You should not
locate a set so that direct rays of light fall upon the face of
the picture tube. This would cause the brilliance of the tube
to be reduced, and it would probably result in glare.
The best location would be one where any light entering the
room will be at right angles to the line of vision of a person
watching the set. Do not locate a set close to a stove or other
source of heat, because the parts inside the set may be damaged
from too much heat. Never block any ventilation holes in the
receiver cabinet for this same reason. A set should be located
several inches out from the wall to allow heat to escape through
the back.

Fig. 3.-A special television lamp will furnish satisfactory
indirect light.





V 1! i '. '
-44







LIGHTING
To prevent eyestrain, the room in which the set is located
should be well lighted from some indirect source. This does not
mean that you should depend on a light in an adjoining room.
To do this would cause eyestrain. You can use an indirect light-
ing fixture on a wall or on a piece of furniture on either side of
the set to furnish a fairly weak light up to the ceiling. Never
let bare bulbs be visible. Or you can use a floor lamp with a
small bulb on one side of the set if no bright bulb can be seen.
Do not place lamps so close to the TV set that light from un-
der the shade falls directly on the screen. Also, avoid placing
lamps so that light is reflected from the screen back into a
viewer's eyes.
Never, under any circumstances, operate a TV set in a totally
dark room. To do so will probably cause severe eyestrain. A
TV set is not like a movie, for its screen is about 10 times

Fig. 4.-A floor lamp properly used will give good light for television.


__ _







brighter than a movie screen. Also, it is many times smaller,
and for these reasons you must provide indirect lighting. Usually
you will obtain best results when you use electric indirect light-
ing, and you reduce light from windows and doors by using
venetian or other blinds.
HOW TO VIEW TV
Do not sit too close to a TV screen to view it. Children are
usually more inclined to do this than adults. Parents should
never allow children to sit closer than six or eight feet from the
screen. Most people will find the best viewing distance is nine
to 15 feet from the screen.
An occasional glance away from the set around the room will
help to keep the eyes from tiring. If the picture is poor because
of interference or poor reception, do not watch it very long at
a time or the eyes will become tired.
Many authorities on eyes believe that television viewed under
proper lighting conditions will not strain the eyes more than
sewing, reading or watching movies.

Fig. 5.-Light from this door may be objectionable.






1 11





|







C._ .







If your TV picture has flicker, snow or poor reception because
of defects in the set, by all means have the set repaired or
replaced.
INSTALLATION AND ADJUSTMENT
You must properly install and adjust your TV set if you
are to obtain best results. In general, you'll find it better
and cheaper in the long run to hire an experienced service-
man to install the set and erect the antenna. If flat unshielded
lead-in wire is installed by the serviceman it should be twisted
once about every foot of length to lessen noise pick-up. Sets
are tested and adjusted at the factory but often minor adjust-
ments will be needed after shipment. Test patterns are broad-
cast at certain times on a station to make it easier for the service-
man to adjust the set properly and to locate trouble.

Fig. 6.-Venetian blinds can exclude light and improve viewing
conditions. Indirect electric light is needed.






CONTROLS
Sets have "major" controls for the serviceman to use for a
major adjustment in the picture and "minor" controls for the
set user to operate in making adjustments. The major controls
are often located on the back or inside of the set because they
will seldom need adjusting, while the minor controls are usually
located on the front or on the side near the front where they
are easy to reach. Only an expert should attempt to adjust the
major controls.
The most common minor controls for the set owner to become
familiar with are the following:
1. Switch and Volume Control-Turns set off and on and con-
trols loudness.
2. Channel Selector-Selects desired channel.
3. Contrast Control-Assists in getting a normal picture that
is not too black or too white.
4. Brightness Control (not present on some sets)-When
used along with the contrast control it helps get a picture that
is pleasing to the eyes.
5. Vertical Hold Control-Stops picture from "rolling over."
6. Horizontal Hold Control (a major control on some sets)-
Stops picture from moving sideways.
7. Tone Control (not present on some sets)-Varies the tone.
8. Other Controls-There may be certain other controls with
a special purpose.
INTERFERENCE
Just as a radio picks up static or noise from electrical equip-
ment or other sources, so will a TV set pick up undesired signals
which show on the screen as interference.
If the interference is serious, better secure an experienced
repairman to hunt the trouble and correct it. Some of the causes
of interference are the following:
1. Other TV stations.
2. Other TV sets (earlier models or defective sets could cause
interference in nearby sets).
3. Short wave and FM stations.
4. Electrical equipment (particularly motors, diathermy
equipment, faulty fluorescent lighting, arc welders, etc. The
interference pattern from most appliances will usually produce
a horizontal bar on the screen).
5. Ignition on vehicles or other engines.
6. Aircraft (when passing overhead may cause picture to
flutter).







7. Power line to set (voltage change and "noise" on the line
sometimes cause trouble. Most sets are not affected by a 5%
change in voltage, either higher or lower than normal. Noise
produced by equipment or by defects along the power line may
follow the electric line to the set).
The serviceman may reduce or eliminate interference by using
a different antenna, a wave trap, or a set booster. Sometimes
shielding or a filter on the equipment causing the trouble will
eliminate interference.
ANTENNAS
For VHF Use.-Many different kinds and makes of antennas
are in use today. In general, they are two types-those made
for a certain channel and all-wave types made to receive chan-
nels 2 to 13. In some locations only one station can be received.
An antenna made for that channel might give better reception.
However, since new stations will be built in the future, it is
recommended that an all-wave antenna be installed.
For UHF Use.-In some cases a regular VHF antenna will
receive UHF satisfactorily. In other cases you will need a small
additional antenna. Whether an additional antenna is needed
will depend on several things, such as the distance from the sta-
tion and the direction of the UHF station compared to the di-
rection of other stations. A special antenna has just been
designed to receive all channels from 2 through 83.
Height of Antenna.-The height necessary for good reception
will vary in different locations. In general, the higher the an-
tenna the better the reception.
Rotating Device.-In locations where stations from more than
one direction can be received, it would be desirable to have a
motor device that will turn the antenna to face the direction of
the station being tuned at the time.
Grounding.-To lessen the danger of lightning, ground the
metal tower or other support for the antenna by using a No. 6
bare copper wire to an 8' ground rod. This ground wire could
also be bonded to a cold water pipe but to do so may result in
interference from telephones or other equipment normally
grounded to a water pipe. Be certain that a lightning arrestor
is installed with the lead-in wire. A small connector could be
fastened in the lead-in wire near the set so the lead-in could be
easily disconnected from the set during severe lightning storms.





REPAIRS
Many of the same parts, such as tubes, resistors and con-
densers, are used in radio and TV sets. The tubes will probably
be the same quality, but one difference exists, however, in the
other parts. Most TV manufacturers put higher quality, more
durable, more expensive parts in TV sets. Though first cost is
mcre than it would be otherwise, in the long run this is a saving
for TV owners. It means fewer breakdowns and lower repair
bills. When a TV set needs repairs the bill may be $10.00 for
labor and 500 or $1.00 for parts. Very likely this bill is a fair
one, for the labor and time required to locate a trouble and repair
it often exceed the cost of parts many times. In addition, the
serviceman must maintain much more expensive equipment
to repair TV sets than is needed for radio sets.
For the first year or so many TV owners have found no repairs
to be needed except the occasional replacement of a small tube.
There are many makes and models of TV sets and sometimes
there are changes during the year a model is made. For these
reasons you can normally expect better servicing from the
repair department of the dealer where you obtained the set.

SAFETY FIRST
Most TV sets have high voltages measured in the thousands
of volts. For this reason an unskilled person who "tinkers" with
a set may be badly injured or killed. Never, under any circum-
stances, work on a set with it turned on unless you are an expe-
rienced repairman. Many sets have more than 1,600 parts, and
it is the job of a skilled person to locate and repair trouble.
Nearly all sets have a safety glass or other protective shield
in front of the picture tube to lessen the chances of its being
broken. If a picture tube is broken the flying glass may cause
serious injury to anyone nearby.
In summary, those desiring the maximum enjoyment and
value from television should obtain a good set and have it
properly installed in the best location in the room. Then with
proper lighting conditions the set should give satisfactory and
pleasing results.

COOPERATIVE EXTENSION WORK IN
AGRICULTURE AND HOME ECONOMICS
(Acts of May 8 and June 30, 1914)
AGRICULTURAL EXTENSION SERVICE, UNIVERSITY OF FLORIDA
FLORIDA STATE UNIVERSITY
AND UNITED STATES DEPARTMENT OF AGRICULTURE
COOPERATING
H. G. CLAYTON, DIRECTOR




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs