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| CD-1000
COIL & DRAIN Instruction
Manual |
| PART
#CD-1000 |
| Click
here to view this item in our Products section. |
| DO
YOU HAVE THSE COMMON TELEPHONE PROBLEMS? |
| Descriptions
and Use: |
| A.
COIN TELEPHONES |
| 1. |
That
are noisy on out-going |
| |
local
calls, but quiet on |
| |
incoming
calls and long |
| |
distance
calls. |
| 2. |
Erratic
and noisy circuits |
| |
due to 60 hertz induced |
| |
AC
voltage. |
|
| B.
KEY TELEPHONE SYSTEMS |
| 1. |
That
have a heavy hum on |
| |
trunk
calls. |
| 2. |
Off-premise
intercom that |
| |
is
noisy while the |
| |
on-premise
station is quiet. |
|
| C.
PABX OR PBX |
| 1. |
Miss
dialing due to more |
| |
than
10 volts, 60 hertz AC |
| |
to
GND. |
| 2. |
Off-premise
extensions, |
| |
noisy,
AC problems. |
| 3. |
Noisy trunks. |
|
|
 |
|
| D.
CENTRAL OFFICES |
| 1. |
That
have unbalanced connectors (many step by
step offices do}...the noise only shows
up |
| |
on
long lines subject to power influence. |
| 2. |
Link
circuits that have a condenser in the tip
and ring (they should be balanced, but often
|
| |
are
not due to replacing one capacitor). |
| 3. |
Unbalanced
loop extenders. |
| 4. |
DX
signaling trunks. |
| 5. |
CX
signaling trunks. |
| 6. |
Simplex
signaling trunks. |
|
| E.
PRIVATE ONE CIRCUITS |
| 1. |
That
will not work properly due to 60 hertz AC. |
| 2. |
Noise. |
|
| F.
FOREIGN EXCHANGE CIRCUITS |
| 1. |
Noisy. |
| 2. |
60
hertz AC problems. |
|
 |
| If
you do have these problems and your trouble is
not caused by bad cable or other facility problems,
Aines Manufacturing Corp. has a new product (a
combined coil and drain) that is effective on
most of these problems. It reduces the 60 hertz
AC and power influence (540 and 900 hertz) before
it can get into the "built in" unbalance
and cause noise or dialing problems. |
|
| This
unit is considerably more effective than conventional
noise chokes and will only add 60 ohms loop resistance.
The transmission loss is less than 0.5 DBM and
in addition, it does not require an expensive
extra pair for its operation. Just cut it in series
with the tip and ring ahead of the unbalance and
provide a good low resistance ground to the unit. |
|
| Most
telephone companies are not aware that much of
their equipment as outlined above have built-in
unbalance. Why? Because of three reasons: |
| 1. |
The
manufacturers did not recognize the problem. |
| 2. |
Equipment
such as PABX, PBX, key equipment, etc. was
most of the time designed to work |
| |
close
to the central office where there is little
if any 60 hertz AC or power influence |
| |
(540
and 900 hertz). |
| |
However,
today we are building our shopping centers,
motels, and business centers in the suburbs
where there is extreme induced 60 hertz
AC and power influence which causes trouble
reports and excessive station visits. It
is a well-known fact a telephone circuit
that is noisy will generate more trouble
reports than one that is quiet. |
| 3. |
It
is many times very difficult to always maintain
good balance. |
|
|
| Listed
below are some of the typical results that can
be obtained from the use of Aines Manufacturing
Corp.'s COIL & DRAIN MODEL CD-lOOO. |
| PI:
|
Power
Influence DBRNC (540 and 900 hertz) CN -
Circuit Noise DBRNC. |
| BAL:
|
Balance
PI - CN = BAL (8ectrical similarity between
tip and ring) 60 DB is the |
| |
beginning
of good balance. Balance below 50 DB is
poor. |
|
| Power
Influence |
Circuit
Normal |
With
Coil & Drain |
| 80
DBRNC |
60
Hertz Circuit Noise |
60
Hertz Circuit Noise |
| 90
DBRNC |
10V
RMS 47.2 DBRNC |
IV
RMS 8.5 DBRNC |
| |
20V
RMS 57.0 DBRNC |
2V
RMS 18.0 DBRNC |
|
| THIS
UNIT IS NOT RECOMMENDED FOR USE ON LINES WITH |
| RINGING
FREQUENCIES OTHER THAN 20 HERTZ. |
| See
attached notes and figures for connections of
the Aines Coil & Drain |
| CD-
1000 and the testing procedures. |
| IMPORTANT
NOTE |
| ANY
TIME THE COIL & DRAIN IS USED IN THE OUTSIDE
PLANT THAT IS BETWEEN. THE CENTRAL OFFICE AND
FIELD EQUIPMENT, STANDARD LIGHTNING PROTECTION
MUST BE PROVIDED ON EACH SIDE OF THE UNIT. |
| WHEN
MOUNTED IN THE CENTRAL OFFICE OR BEHIND STANDARD
OUTSIDE PLANT PROTECTION (STATION PROTECTORS),
NO OTHER PROTECTION IS REQUIRED. |
| COIL
& DRAIN Installation
Instructions |
| All
noise chokes or coil and drains are for use on
lines that have induced longitudinal voltages;
that is, a voltage flowing in both the tip and
ring conductors with the same polarity at anyone
given instant in time. They are not effective
for metallic voltages. |
| Simple
test to determine if Aines Coil & Drain CD-I000
will help your problem: |
| STEP
I |
| A. |
Dial
up quiet termination at central office.
|
| B. |
At
far end, measure noise to ground + 40 DBRN
= PI. |
| C. |
Measure
noise metallic or circuit noise. |
| D. |
Calculate
balance = PI - CN. |
|
| The
balance must be 60 DB or higher. |
| STEP
II |
| E. |
Remove
field equipment (coin/tel., PBX, key equipment,
etc.). |
| F. |
Place
a termination test set, or a 120 G or H
repeating coil connected as in FIG. 1 |
| |
in place of the field equipment. |
| G. |
Remake
all measurements A, B, C and D in STEP I.
If D is now higher than the first |
| |
measurement,
the Aines Coil & Drain will give you
greater improvement. |
|
|
If
the circuit did not improve or did not improve
enough, leave the coil placed in FIG. 1 in place,
and place a second coil 120 G or H or termination
set on the cable pair in the central office. You
must
disconnect the central office from the field and
measure A, B, C and D. See FIG. 2. |
| 1. |
If
D has now improved (higher) you need a coil
and drain at the central office. |
| 2. |
If
some improvement was obtained with the first
coil and additional improvement with the
|
| |
second
coil, then it would be helpful to use a
coil and drain at both the field and central
office. |
| 3. |
If
no improvement is obtained with FIG. 2 (balance
less than 60) then you have trouble |
| |
in your facilities. |
| |
Some
times noise is caused by the connection
of open wire and cable. |
| |
Where
this occurs it is often caused by induced
voltage 60AC power influence working on
|
| |
the
unbalance either in the cable or the unshielded
wire. Where this trouble is experienced,
|
| |
the
coil and drain must be tried. Place it in
series with the line with the facility leads
toward |
| |
the
shielded cable and the equipment leads towards
the unshielded wire. Measurements are |
| |
then
made as per STEP I at the far end of the
circuit. The coil and drain leads are then
|
| |
reversed
and measurements remade. Use the condition
that gives the best results. |
|
| Connections
of Tern1ination Test Set or 120 H or 120 K Repeat
Coil: |
 |
| All
measurements should be made from field end. |
| AC
measurements are made one side to ground through
1 uf capacitor. |
| Coil
and Drain Connections: |
 |
| Typical
connection of coil and drain for PBX, PABX, Coin
Telephone, or other field mounted equipment effected
by longitudinal 60 hertz, AC voltages, and/or
noise (540 hertz-900 hertz) due to unbalance in
the equipment or equipment sensitive to 60 hertz
AC induction. |
 |
| Typical
connection for central office, tandem trunks or
similar equipment. |
 |
| Typical
connection when unbalance is encountered in equipment
at both ends of the circuit, c.o. interoffice
or C.D.O. trunks, DX, or CX signaling, coin telephone,
PBX, PABX, key equipment, etc. |
| At
the station and junction and C.O. |
| Typical
locations single line drawing. |
 |
| At
no time should any part of the circuit be removed
except the c.o. or field equipment unless it is
replaced by a termination as in FIG. 1 or FIG.
2. |
| All
side legs or bridge taps must remain connected
if a true picture of the noise is to be seen.
|
| Coil
and Drain at the junction of Cable and Open Wire. |
 |
| The
coil and drain is often helpful placed at the
junction of cable and open wire or cable and buried
service wire, cable and R.D. W., cable and Birdwire,
or any unshielded wire. |
|
| As
a general rule the problem is power influence
feeding off of the open wire into an unbalance.
Usually, the facility side of the coil and drain
will connect to the open wire, and the equipment
side will connect to the buried service wire or
the unbalance. |
|
| The
surest way is to try it both ways; all measurements
made at the far end using the position with the
best results. Two coil and drain units may be
required. |
