Eico 779a sentinel pro User manual

,

•

779A

Sen

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Pro

CB

Transceiver

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SECTION 1. GENERAL DESCRIPTION

The EICO 779A/Senti11el

Pro

is

a full

5-watt

input

(legal

limit)

CB

transceiver

incorporating

a

modern

highly efficient 23-channel frequency

synthesizer

circuit

capable

of

providing

crystal-control-

led

transmit

and

receive

on

all

authorized

CB

channels,

with no

further

crystals

ever

needed. A

single

control

selects

the

transmit

and

receive

channels

with channel

numbers

1

through

23

appearing

in

an

illuminated

window.

Provisions

are

made

for

the

addition

of

extra

channels

if

and

when

author-

ized

by the FCC.

The

receiver

is

a dual

conversion

superheterodyne

incorporating

full

electronic

switching

in

the

antenna

circuit

(eliminating

possible

noisy

and

arcing

relays),

a

27

MC

preselector,

a

crystal-con-

trolled

6

MC

converter,

one

stage

of

high-gain

6

MC

IF,

a

crystal-controlled

455

KC

converter,

followed by two

high-gain

455

KC

IF's.

Sensitivity

is

rated

at

O.

25uV

for

lOdb

signal-to-noise

ratio.

Excellent

adjacent

channel

rejection

is

achieved without

excessive

narrowing

of

the

desired

channel

bandpass

since

the 6db down points

of

the

selectivity

curve

are

only 3

KC

from

the

desired

carrier

frequency.

Primary

image

rejection

is

better

than 60db

(better

than

1 million

times).

A

front-panel

bandspread

control

permits

accurate

tuning of

stations

that

may

be

transmitting

slightly

off

frequency.

The wide dynamic

ran

ge

of

the

AGC

circuit

prevents

overloading

on

strong

local

signals

while

an

automatic

impulse

noise

limiter

and

an

adjustable

squelch

are

provided

for

operator

comfort.

An

illuminated

front-panel

dual-function

meter

serves

as

an

"S"

(signal

strength)

meter

when

receiving.

In addition to the

built-in

4-inch

loudspeaker,

headphones

or

an

external

remote

speaker

may

be

con-

nected

simply

by plugging into a

front-panel

phone

jack.

This

automatically

'

silences

the

built-in

speaker.

The

efficient

5-watt

transmitter,

of the

latest

frequency-synthesis

type,

provides

in

e~cess

of

3

watts output. An

exclusive

feature,

"Finger-Tip

Tuning",

is

provided

so

that

the

operator

can,

at

any

time,

without

tools,

tune the

transmitter

output to

match

almost

any

antenna

between

30

and

100

ohms impedance

so

as

to

get

maximum

transmitter

RF

output. An

adjustable

TVI

filter

permits

attenuation of any

harmonics

that

might

interfere

with

local

TV

reception

on the

lower

VHF

channels.

When the exclusive "Range

Plus"

feature

is

switched

in

(via

a

front-panel

switch), a

very

high

average

level

of

modulation

can

be

used

thus

increasing

the

effective

output

power

of

the

signal,

making

it

more

readable

at

a distance.

This

exclusive

feature

also

automatically

compensates

for

various

operator

voice

levels

so

that

whether

the

operator

speaks

in a

normal

voice

or

shouts,

or

if two

or

more

operators

having

vastly

different

voice

levels

use

a common 779A/Sentinel

Pro,

the

modulation

will

remain

high,

yet

will not

overmodulate.

A

PA

/CB panelswitch

permits

the

receiver's

audio

amplifier

to

serve

as

a 3.

5-wattpublic-address

(PA)

amplifier

when

an

external

speaker

(or

bullhorn)

is

pluggedinto the

rear

receptacle

thus

marked.

For

use

as

a PA

system,

simply

depress

the mike

push-to-talk

(ptt)

switch.

With

the

mike

button

untouched, incoming

signals

on the

selected

CB channel

can

be

heard

over

the

PA

system

if

desired.

In

certain

base

station

operation,

this

permits

incoming

messages

to

be

heard

atremote

points

in

the

base

station

area.

In mobile

operations,

it

permits

incoming

messages

to

be

heard

while the

opera-

tor

is

outside and

some

distance

away

from

his

vehicle.

The EICO 779A/Sentinel

Pro

uses

a high-efficiency

transistor

switching

power

supply

and

can

be

operated

either

from

a

source

of

117 VAC,

or

from

a

source

of

12

VDC

(such

as

in a

car

or

boat)

having a negative ground. Individual

power

cords

for

both

modes

of

power

input

are

provided.

For

positive-ground

vehicles,

or

where

it

is

desired

to keep the 779A/Sentinel

Pro

independent of ground

polarity,

the EICO DCS-5

conversion

kit

is

available.

See

your

local

EICO

dealer.

UNPACKING

This equipment has

been

thoroughly

tested

and

inspected

before

packing.

If

you find

visible

damage

upon

unpacking, notify the

dealer

at

once.

If

the

unit

was

shipped, you

must

file

a

claim

with the

carrier,

since

only you

can

recover

for

shipping

damages.

Your

dealer

and EICO

will

cooperate.

COPYRIGHT

©

1966

EICO

ELECTRONIC

INSTRUMENT

COMPANY,

Inc

.

1

•

'

WARRANTY

POLICY

Please

read

the

EICO WARRANTY

and

note

that

the

registration

card

accompanying

each

unit

should

be

filled

in

and

returned

to the

company

within

10

days

of the

date

of

purchase.

The

warranty

applies

only

if

we

have

your

registration

card

on file.

CITIZENS RADIO LICENSE

If

you do

not

have

a

Citizens

Radio

License,

fill

out

FCC

Application

Form

505 (supplied)

and

mail

it

immediately

to the.

Federal

Communications

Commission,

Gettysburg,

Pennsylvania

17325.

As

of

March

17, 1964,

payment

of a

fee

of $8. 00*

is

required

upon

filing

this

application,

anda

check

or

money

order

for

this

amount

must

accompany

the

application.

(As the

fee

situation

may change,

it

would

be

wise

to

check

with

your

dealer

at

the

time

of

filing

the

license

application)

o

You

may

expect

to

receive

your

license

within

10-14

days.

In

filling

out

Form

505,

note

that

this

equipment

is

intended

for

Class

D

service.

Note

also

that

you

must

certify

that

you

have

in

your

possession

(or

have

ordered

from

the

Guvernment

Printing

Office,

Washington, D.

C.)

a

current

copy

of

Part

95

concerning

the

rules

and

regulations

of the

Citizens

Radio

Service.

Attached

to

Form

505

is

an

Order

Blank

for

Part

95

which you

must

mail

to

the

Government

Printing

Office to

meet

this

requirement

if

you do

not

already

have a copy. When

you

receive

your

copy

of

Part

~5,

read

it

carefully

(and

be

sure

you

understand

it)

for

your own

pro-

tection.

*Government

entities

are

exempt.

WARNING

It

is

absolutely

forbidden

to

transmit

with

your

equipment

until

you have

received

your

license

and

call

sign

from

the

FCC.

There

are

severe

penalties

for

such

illegal

opera-

tion.

(Using

your

equipment

for

receiving

only,

however,

is

perfectly

legal)

o

Note

that

any

U.S.

Citizen

18

years

or

older

may

obtain

a

Citizens

Radio

license.

There

are

no

requirements

for

understanding

of

radio

theory

or

mastery

of

Morse

Code.

Corporations,

partner-

ships,

and

associations

as

well

as

government

entities

and

organizations

operated

by

their

authority,

may

also

be

licensed

in

the

Citizens

Radio

Service.

The

units

of

any

Class

D

station

licensed

in

the

Citizens

Radio

Service

are

authorized

primarily

to

communicate

with

other

units

of

the

same

station;

secondarily,

units

of

Class

D

stations

are

author-

ized

to

intercommunicate

with

units

of

other

stations

in

the

Citizens

Radio

Service

only when

necessary

for

exchange of

substantive

messages

business

or

personal

activities

of the individuals

concerned.

TRANSMITTER IDENTIFICATION CARD

When you have

received

your

license,

fill

out

the

Transmitter

Identification

Card

FCC

Form

452-C

(supplied)

and

attach

it

to

your

equipment

(required

by

law).

CALLING PROCEDURE

The

proper

calling

procedure,

including the

required

use

of

the

station

call

sign

and

the

permis-

sible

length

of a

transmission

exchange

and

other

matters

relating

to

correct

operation,

are

described

in

Part

95

referred

to

above.

USEFULNESS

OF

23-CHANNEL OPERATING CAPABILITY

Licensees

in

the

Citizens

Radio

Service

are

authorized

to

transmit

or

receive

on

all

of the

23

Citizens

Band

channel

frequencies.

The

EICO 779A

Sentinel

Pro

is

capable

of doing

so

JUSt

as

sup-

plied;

with

no

additional

crystals

needed.

As

there

are

no

channel

assignments

to

particular

stations,

the

twenty-three

channel

capability

is

entirely

useful.

It

provides

the

fullest

possible

assurance

that

conflict

may

be

avoided

with

existing

or

future

stations

in

the

area.

Furthermore,

certain

channels

have

been

established,

by

mutual

agreement

of

licensee

groups,

as

the

channel

that

would

be

monitored

by

all

of

a

particular

group

for

a

specific

purpose.

These

channels

and

their

specific

purposes

are

listed

below:

Channel 9:

National

calling

and

emergency

channel

for

all

stations.

Officially

adopted

by

REACT

(Radio

Emergency

Associated

Citizens

Teams)

which

has

about

600

teams,

and

700

to 800

other

individual

clubs

across

the

country.

The

members

of REACT

and

the

other

individual

clubs

are

committed

to

monitoring

Channel 9 to

provide

emergency

contact

for

travelers

and

others,

wherever

and

whenever

needed.

Channel 13: Unofficial

monitoring

channel

for

non-commercial

(pleasure)

vessels.

As of

this

writing,

there

are

proposed

FCC

rulings

which

it

is

believed

will

become

official

shortly,

concerning

the

permitted

use

of

each

of

the

23

Citizens

Radio

channels.

If

these

rulings

become

official, they

will

be

incorporated

in

the

current

Part

95.

The

substance

of

the

new

rulings

is

to

per

-

mit

only

seven

channels

(9, 10, 11, 12, 13, 14, 23) to

be

used

for

communications

between

units

of

different

stations

(inter-station

communication)

while

permitting

all

channels

(1

through

23) to

be

used

for

communication

between

units

of the

same

station

(intra-station

communication).

However,

any

channel

in

this

service

may

be

utilized

during

an

emergency

involving the

immediate

safety

of

life,

or

the

immediate

protection

of

property,

for

the

transmission

of

emergency

communications,

provided

notice

and

an

explanation

is

given

as

soon

as

possible

thereafter

to

the

FCC

in

Washington, D.

C.

and

the

Engineer

in

Charge

of the Radio

District

in

which the

station

is

located.

SECTION 2. INSTALLATION

VENTILATION

In

all

installations,

consideration

should

be

given

to

adequate

ventilation

in

placing

the unit. The

slotted

vents

in

the

top

and

rear

of

the

cabinet,

and

the

vent

holes

in

the

bottom

plate,

must

not

be

blocked

at

any

time

if

the

normal

heat

generated

by

the

tubes

is

to

be

removed

by

convective

air

movement.

If

heat

removal

is

prevented,

an

excessive

temperature

rise

will

occur

in

this

unit

which

can

damage

components.

In

any

installation,

avoid

placing

the

unit

in

or

near

a

hot

air

stream.

BASE & MOBILE POWER CONNECTIONS

The

779A/Sentinel

Pro

may

be

used

as

a

base

station

(fixed location)

in

which

case,

AC

power

(117 VAC, 60

cps)

is

normally

used;

or

it

may

be

used

as

a

mobile

station

on

a

land

vehicle

or

boat

of

any

type,

in

which

case

12 volt

battery

power

is

used.

Individual

AC

and

DC

(battery)

power

cables

are

supplied

and

the

appropriate

one

must

be

selected

for

the

type of

operation.

Both

AC

and

DC

power

cables

are

terminated

at

one

end

by

an

octal

socket

for

insertion

in

the

rear

octal

plug

on

the

transceiver.

They

may

easily

be

distinguished

by

the

line

outlet

plu

g

terminating

the

other

endof

the

AC

power

cable,

and

the

bare

wire

ends

terminating

the

other

end

of

the

DC

power

cable

(which

also

incorporates

an

in-line

fuse

for

DC

operation).

Please

note

that

the

779A/Sentinel

Pro

may

be

used

in

12

VDC

negative

ground

vehicles

only.

For

positive-ground

vehicles,

or

where

it

is

desired

to

keep

the ''779/

Sentinel

Pro"

independent

of

ground

polarity,

the EICO DCS-5

conversion

kit

is

made

available.

See

your

local

EICO

dealer.

In mobile

installations,

the

fused

(red)

lead

of the

DC

power

cable

may

be

connected

to

the

ACC

terminal

of the ignition

switch

or

fuse

panel

only

if

the full

battery

voltage

is

available

at

this

point

with no

losses

due to

ballast

resistors.

If

full

battery

voltage

is

not

available

at

the

ignition

switch,

connect

the

fused

(red)

lead

to

the

starter

relay

terminal,

which

has

a

direct

low-loss

connection

to

the

battery

positive

terminal.

In

all

cases,

connect

the

unfused

(black)

lead

of

the

DC

power

cable

to

the

nearest

good

chassis

ground

in

the

vehicle.

Note

that,

with

the

ignition

switch

connection,

there

is

no

danger

that

the

battery

will

be

run

-down

if

you

forget

to

turn

the

unit

off

before

leaving

the

vehicle,

nor

is

there

risk

of

unauthorized

operation

of

the

unit

while

you have the key.

However,

the

ignition

switch

connection

will

always

introduce

more

power

losses

than

the

"hot"

lead

(starter

relay)

connec-

tion

because

of

the

smaller

cable

and

the

extra

connections

between

unit

and

battery.

3 -

-~---

..

MOBILE

MOUNTING

BRACKETS (A8 B)

SOLID

LINE-

TURNED

INWARDS

DOTTED LINE-

TURNED

OUTWARDS

NOTE

THE

CORRECT

POSITION

OF

OPEN-ENDED SLOT

IN

THE

VERTICAL

LEG

OF

EACH

BRACKET

.

f

LOCKWASHER

f-20

THUMBSCREW

·

,,-

rd'

~

It

l

=11:6

HEX

HEAD / l - Ii -

MIC.

BRACKET

11i

152

8

FIGURE

1

'

,,

'

,,

'

t-20

NUT

(NOT SUPPLIED)

•

~

LOCKWASHER (NOT SUPPLIED)

t

,,,..

"',,,

...

.:~

.......

,,

.;

;.:,

,

~)

t

~~.......

41:*

.---

MOBILE

MOUNTING

BRACKE

'

MOUNTED

UNDER

DASH

...

*

**

--

-

l,

CABINET

MOUNTING

BRACKET

1•

--20

SCREW

4

(NOT

SUPPLIED)

~FRONT

OF

UN

IT

MICROPHONE

BRACKET

(C)

SOLID

LINE-HORIZONTAL

POSITION

(MOBILE/BASE)

DOTTED

LINE

-VERTICAL

POSITION

(BASE ONLY)

•

MICROPHONE BRACKET MOUNTING

The

microphone

bracket

and

the

required

mounting

hardware

are

supplied

separately

for

n:iounting

by the

installer.

The

mounting

is

shown

in

Fig.

1. Note

that

there

are

two

po

·

ssible

mounting

posi-

tions

for

this

bracket,

one

permitting

the

microphone

to

slip

in

and

out

vertically

and

the

other

permit-

ting

t1'e

microphone

to

slip

in

and

out

horizontally.

In

base

installations,

t,he

vertical

btack~.t

mounting

is

probably

more

convenient.

In

mobile

installations,

horizontal

mounti

·hg

of

the

bra«ket

1

is

usually

the only

one

practical.

MOBILE INSTALLATION MOUNTING

The

method

of

mobile

mounting

devised

for

the

779A/Sentinel

Pro,

as

shown

in

Fig.

1,

permits

the

unit

to

be

installed

and

locked

in

place,

or

released

and

lifted

out,

all

in

a few

moments

without

the

need

for

tools.

This

facilitates

servicing,

or,

if

desired,

double

use

of

the

779A/Sentinel

Pro

as

both

mobile

and

base

station.

It

also

makes

it

easy

to

transfer

the

trunk

of

the

vehicle

(or

remove

it

entirely)

to

safeguard

it

from

theft.

The

mobile

mounting

hardware

consists

of

two

different

L-

brackets

to

be

mounted

usually

on

the

underlip

of

the

dash

directly

over

the

center

hump.

The

brackets

may

be

mounted

either

both

turned

outwards

or

both

turned

inwards,

depending

on

the

positions

of

existing

holes,

or

space

limitations.

Having decided on

either

the

outward

or

inward

configuration,

it

may

be

determined

which

bracket

is

left

and which

is

right

by

noting the

angled

hooking

slots

in

the

vertical

legs

of the

brackets,

and

choosing which

bracket

is

to

be

left

and

which

is

to

be

right

by

the

criterion

that

the

closed

end

of

the

slot

must

be

lower

than

the

open end

so

that

the

unit

can

not

drop

out

if

the

locking

screws

ref

erred

to below should

loosen.

The

horizontal

leg

of

each

bracket

has

a

slot

rather

than

a

single

mounting

hole

in

order

to

permit

convenient positioning

adjustment

and

to

make

the

locations

of

the

drilled

holes

in

the

dash

less

critical.

In Fig. 1 the

distance

between

centers

of the

slots

in

the two mounting

brackets

is

given

for

both the

inward

and

outward

bracket

mounting

positions.

The

bracket-mating

attachments

to the

unit

and

the

required

mounting

hardware

are

also

supplied

separately

for

mounting

by

the

installer.

The

mounting

is

shown

in

Fig.

1. When the

locking

screws

are

loosened,

the

unit

may

be

hung on

the

mounting

brackets

and

the

locking

screws

tightened

to

secure

it.

In

determining

the

positions

of

the

mounting

brackets,

be

sure

they

are

placed

far

enough

forward

so

that

there

is

enough

room

behind the

unit

for

the

power

cable

plug

and

that

there

is

no

chance

of

the power supply

transistors,

mounted onthe

rear,

coming

into

contact

with

a

metal

part

of

the

vehicle

(firewall)

and

thereby

causing

a

short

circuit.

MOBILE INSTALLATION NOISE & INTERFERENCE SUPPRESSION

Surrounding

noise,

in

mobile

installations

is

usually

much

greater

than

in

base

installations.

For

this

reason,

the

units

location

should

be

chosen

so

that

it

is

possible

to

hear

all

messages

distinctly.

Furthermore,

engine

interference

may

be

encountered

in

mobile

operation.

This

type

\

of

interfer-

ence

varies

with differ.ent

vehicles.

It

is

generally

caused

by

either

the

ignition

system,

\

the

genera

-

tor

system,

or

the voltage

regulator.

Should

such

interference

be

encountered,

several

suggestions

for

noise

suppression

are

offered:

a) Ignition

noise

is

characterized

by

regular

popping

or

snapping

as

heard

in

the

speaker.

It

will

vary

with the

speed

of

the engine.

This

type of

interference

maybe

reduced

by

proper

vehicular

preventative

maintenance,

plus

the

addition of

proper

noise

suppression

component

items.

Check

the

ignition

system

connections

and

the

distributor

cap

and

points.

If

necessary,

replace

worn

ignition

components,

and

clean

and

adjust

the

spark

plugs.

Replacement

of

standard

equipment

ignition

wire

with

resistance

ignition

wire

may

prove

helpful.

Ignition

interference

may

also

be

reduced

by

the

5

MARINE ANTENNA SYSTEMS

For

marine

use,

it

is

possible

to

use

quarter-wave

mobile

antennas

with

a

ground

plate

of

tin-foil

or

copper

installed

on the

underside

below

the

water

line.

A

recent

type of

base

station

antenna

particularly

suitable

for

marine

use

is

the

fiberglass

half-wave

coaxial,

which

does

not

require

any

grounding

provisions,

since

the

antenna

effectively

contains

its

own ground.

One

maker

offers

both

a

full-length

type

(18-1/2

feet),

requiring

support

afewfeetup

from

its

base,

anda

shortened

coaxial

with

embedded

loading

coil

(

10-1/2

feet)

that

is

somewhat

less

efficient

but

requires

no

support

other

than

its

base

and

is

more

suitable

for

smaller

boats

that

have no

cabin.

GROUNDING

Scrupulous

attention

should

be

given to

the

grounding

instructions

given

with

your

antenna,

both

for

personal

safety

and

equipment

safety

in

electrical

storms,

as

well

as

optimized

performance.

The

shield

of

the

coax

cable

from

the

antenna

may

serve

as

both

operating

and

protective

ground,

but

this

coax

shield

must

be

connected

to a good

earth

ground,

which

may

be

a

nearby

cold

water

pipe,

rigid

conduit,

metal

building

frame,

or

a

metal

ground

rod

(at

least

8

feet

long)

driven

into the

ground

for

this

purpose.

The

ground

lead

should

be

at

least

No. 8

aluminum

or

No.

10

copper

wire

(which

need

not

be

insulated) and

run

it

as

short

and

direct

as

possible

from

a

chassis

ground

terminal*

at

the

rear

of the unit. Note

that

lightning

arrestors

are

not

necessary

when the

coax

cable

shield

serves

a

ground and the

unit

itself

is

grounded

as

described

above,

but

co-ax

type

arrestors

may

be

used

for

the

protection

they

offer

the

shield.

If a

co-ax

arrestor

is

used,

it

should

be

placed

near

where

the

coax

enters

the house (but away

from

combustible

material),

and

a

ground

wire

must

be

connected

to

it

so

that

it

will

serve

its

purpose.

In

addition,

the

antenna

mast

should

be

grounded,

also

with

No. 8

aluminum

or

No.

10

copper

wire.

In making

ground

wire

connections

to a

cold

water

pipe

or

ground

rod,

use

clamps

to

assure

positive

contact.

*ground

lug

on

rear

panel

mounting

screw.

ANTENNA CABLE

If the antenna

base

is

within 2

feet

of

the

unit,

as

may

frequently

occur

in

mobile

or

marine

installations,

connect

#16

standard

insulated

wire

from

the

center

terminal

in

the

antenna

base

to the

center

terminal

of the

coax

plug (PL259) going to the

unit.

Then

run

No. 8

aluminum

or

No.

10

copper

wire

from

a

chassis

ground

terminal

on

the

rear

of

the

unit

directly

to

the

nearest

good ground

point

in

the

vehicle.

If a

longer

run

is

required,

use

RG58/U

coax

cable.

It

is

possible

to

obtain

various

lengths

(20,

50,

or

100

feet

for

example)

with

a

PL-259

coax

connector

at

one

end.

To

insure

proper

transmitter

loading

and

the

best

results

for

various

types

of

antennas,

the

coax

cable

must

be

trimmed

to 11

feet

9 inches

(1

/ 2 wavelength)

or

any

multiple

thereof

(23

feet

6

inches,

35

feet

2

inches,

47

feet,

etc.).

Select

the

nearest

multiple

that

will

meet

the

required

run

distance,

with

allowance

for

routing,

and

trim

the

cable

to

this

length. On

the

antenna

·

end,

prepare

the

cable

and

connect

it

to

the

antenna

as

stipulated

by

the

antenna

manufacturer.

On the

set

end,

plug

the

PL-259

coax

connector

into the

antenna

connector

on

the

rear

of the unit.

Be

sure

to

observe

grounding

instructions.

SECTION 4. OPERATION

FUNCTIONS

OF

CONTROLS & TERMINALS

OFF

switch

/VOLUME

control

--

Combinedpower

on-off

switch

and

receiving

volume

control.

Volume

control

has

no

effect

in

transmit

or

PA

use.

MICROPHONE

receptacle

-

Mates

with

connector

of

ceramic

noise-cancelling

mike

provided.

Polar

-

ized to

prevent

wrong

insertion.

7

12.

For

PA

(Public

Address)

use,

an

external

speaker

must

be

connected

to the PA OUTPUT phono

jack

at

the

rear

and the PA/CB

switch

on

the

panel

set

to

PA.

The

panel

VOLUME

control

has

no

control of the

external

speaker

volume

in

PA

operation

and

should

be

turned

clockwise

from

OFF

to the minimum

volume

position.

If

control

of

the

external

speaker

volume

is

desired,

use

a 4-ohm

or

8-ohm

L-pad,

depending on

the

external

speaker

impedance.

PA

operation

is

obtained with the

mike

p-t-t

button

held

down;

incoming

signals

on

the

selected

channel

will

be

heard

over

the

external

speaker

with

the

mic

p-t-t

button

up.

The

internal

speaker

is

not

used

in

PA

operation.

NOTE: Use the

microphone

properly

to

avoid

distorted

transmissions.

Hold

it

about

4

inches

away

and angled

slightly

toward

the

mouth.

Speak

past

the

microphone

rather

than

at

it.

*Asterisk denotes

initial

set-up

or

adjustment

step

not

part

of

normal

operating

procedure.

13.

To

take

advantage

of

the

RANGE

PL

US

feature,

place

the

RANGE

PL

US

switch

in

the

ON

position.

NOTE:

For

maximum

efficiency,

an

output

power/field

strength/V.S.

W.R.

meter,

such

as

the EICO

715

Trans-Match

should

be

used

in

accordance

with

its

instructions.

SECTION 5. MAlliTENANCE

REMOVAL

FROM CABINET

To

remove

the

instrument

from

the

cabinet,

first

disconnect

it

from

the

power

line

and

remove

four

#6

sheet

metal

screws

from

the

bottom.

Unit

can

be

removed

from

front

or

rear

of cabinet.

SERVICE

WARNING

The

voltages

in

this

instrument

are

dangerous.

Take

caution

to avoid

personal

contact

with

these

voltages

when

the

instrument

is

being

operated

outside

of

its

cabinet.

Th~

unit

is

accurately

aligned

and

adjusted

at

the

factory

and

should

remain

so

in

normal

use.

Wax

or

glyptol has

been

placed

on the

alignment

and

adjustment

points

and

evidence

of

tampering

shall

void the

warranty.

People

without

electronic

knowledge

or

experience,

should

confine

their

own

servicing

to tube

or

fuse

replacement.

(Please

note

that

the

6BQ5 tube

V4

is

replaceable

only by

an

RCA

6BQ5

or

an

EICO-supplied

replacement.)

People

with

electronic

knowledge

and

experience

may,

Ln addition,

undertake

replacement

of the

relay

or

parts

in

the

power

supply, audio

section,

and

meter-

circuits,

as

well

as

any of

the

crystals,

providing

(and only providing)

that

these

are

EICO-supplied

replacement

crystals

for

this

unit. Only

qualified

technicians

with

proper

equipment

may

undertake

/

realignment

or

tuning

adjustments

of

either

the

receiver

or

transmitter

sections.

Note,

furthermore,

that FCC

regulations

require

that

any

transmitter

adjustments

(other

than

output/antenna

tuning) be

~

made by,

or

under

the

supervision

of

a

person

holding a

1st

or

2nd

class

commercial

radiotelephone

license.

The

chart

below

shows

the

crystal

pair

used

for

each

of

the

24

channels.

Each

row

and

column

s the group of channels

that

will

be

"out"

if

the

particular

crystal

heading that

row

or

column

is

aefective.

12\c

M

4.635

4.625

4.615

4.595

M)\C

4.635 4.625 4.615

4.595

37.60 1 2 3 4

37.75

13

14

15

16

37.65 5 6 7 8 37. 80

17

18

19

20

•

37.70 9

10 11 12

37.

85

21 22 22A 23

10

Y'-J.U

.l~U.l!i

v.l~.C\.

.l

#1

#2

#3

#4

#5

#6

#7

#8

#9

R T R T R T R T R T R T R T R T R T

Vl

75 75

-5.5

.

-5.

5 75 75 0 0

6.3

6.

3 90 90 0 0 0 0

-2

6GH8 AC AC

V2

-3

50

-2

.

-3 -3

50

6.

3

6.

3

12.6

12.

6

-3

225 0 0 0 0

-5

-13

6GH8 AC AC AC AC

V3

-.4 -.2

0

.7

6.

3

6.

3 0 0

--3.

2 240

-3.

2 200 0 0

6BH6

AC

V4

1. 6

1.6

-105

*-6

0 0 6. 3

6.

3

12.6

1.

6

1.6

280 240 1. 6

1.

6 280 230

6BQ5 AC

AC

AC AC

V5 110 0

-1

-50

85 0

6.

3

6.

3 0 0 250 0

.6

0 3. 2

.8

0 0

6GH8 AC AC

V6

*-12

0 0 0

12.

6

12.6

0 0 *80

-.45

*75 0

-.4

0 -

12BEG

AC AC -

V7

6BA6

-.

3

-50

0 0 0 0 6. 3

6.

3 130 0 70 0 •

65

0

AC

V8

-.

2

-50

0 0

12.6 12.6

6.3

6. 3 250

-.45

100

-.45

2.5

0

6BA6 AC AC

AC

V9

6. 3

6.

3 0 0 0 0 0 0

-.

3

-.

6 28 38 68 75

!6

to 0 0 0

6EU7 AC AC 27

VlO 0 0

12.5 12.5

6. 3

6.

3

12.6

280 260 250 255 0 0

6AQ5 AC AC AC AC i

NOTES:

1.

R =

Receive

T =

Transmit

t

Variable

on

Squelch

Contro

l

2.

All

readings

are

in

volts

DC

unless

AC

is

stated

3.

*Indicates

voltage

is

variable,

depending

upon

alignment

of

unit

4.

All

other

voltages

may

vary

±10%

with

117VAC

line

voltage

Eico 779A Sentinel Pro User manual

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