Memorex CP8 TURBO UNIVERSAL REMOTE CONTROL Manual de usuario descargar pdf (Pagina 38)

42

Fig.

9- In 1940, Philco

and Zenith

supplied Ford with

car

radios

that had the

antenna rod coming

straight through the

roof

and plugged into the

top of the receiver.

bumper.

known as the "straight protector;" in

front

of

the

grille; even on the hinge pin of a car door.

Some rod -type antennas defy description, such as

the

Insuline "Vidi- Tenna"

which

looked -and was

advertised -

as a miniature television

antenna. Or the 1937 "Clipper" by

the Galvin Manufacturing

Corporation,

which was

a com-

bination of roof

and

rod

antenna, and

which was,

according to

the December

1937 issue of Radio News, "styled in the

modern

manner to match the stream -lined automobile" It's

shown

in Fig. 10.

Fig.

10

-This is the

"Clipper" antenna which

was a

combination

of

roof

and rod antenna,

and was

styled to

match

the

steam -lined

automobiles

of

the time.

In

1950, Insuline

came up with

the "Tenna-

Beam,"

a 24

",

two -section,

rod aerial with

a pilot

light built

into the

base to

offer

"additional

antenna protection," with

a "special light

-

transmitting

jacket"

that carried

the light

completely

up the

antenna

shaft (Figure

II). In

addition,

the aerial

had two red

discs

on the

top that glowed

brightly

in the

day -time.

Windshield

Antenna

The

rod antenna

met the

requirements

of in -car

reception

quite successfully,

but

then,

with

the introduction

of the

windshield

antenna in

the 1969 Pontiac

Grand

Prix, the

car -

radio

industry

completed

one of its

many full

circles.

Joseph M.

Callahan, former

engineering

editor of Auto-

motive

News,

reported in

1968 that "auto

engineers

have been

trying

to get rid of

the outside radio

antennas

in cars for 40

years, but

it remained

for the innovation

-minded

engineers

at

Pontiac

to successfully

accomplish

this on

the 1969

Grand

Prix.

On this car,

the antenna

will

consist of

two pieces of

wire

thousandths

of

an inch in diameter

that will

be sand-

wiched

between two

layers of laminated

glass in

the

wind-

shield.

The slightly

-visible

copper

wire

will run

up the center

of

the

windshield

and

across the top

toward the A- pillars,

forming

a half -wave

dipole."

Fig. 11 -In

1950, out

came the

"Tenna- Beam,"

a

24

two -section,

rod

aerial with

a pilot light built into

the

base. The

jacket

carried light

up the antenna

shaft.

Besides

its

better reliability,

the windshield

antenna had

two

major advantages

over

the telescopic

rod: it reduced

the

clutter outside

the car

and

was

always "extended"

full

-length

for optimum

radio reception.

Its

major disadvantage,

as

compared

to a fully-

extended

56" or 32"

whip,

was

a 16 dB

loss

in AM sensitivity.

Making it

Better

Ken

Jensen, an electrical

development

engineer

at General

Motors, was

credited with

the idea of

bringing the thin wires

up the middle

of the windshield

which,

by reducing

stray

capacitance, improved

AM reception

to some

degree over the

original proposal

of running

the wires

up near the

pillars.

While

at

first there

was

some

concern

that

wires

in the

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