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NEW
www.sandman.com
Mike Sandman... Chicago's Telecom Expert
390 E. Irving Park Rd. Roselle, IL 60172 630-980-7710
Page 47
LOOP CURRENT TECH BULLETIN
Also:
INSTRUCTIONS FOR DETERMINING LOOP LOSS IN db
Loop Current is the amount of electrical energy flowing through
the telephone and line, as opposed to the voltage which is the
force behind the energy. There is a definite correlation between
the Loop Current and Line Voltage (Ohms Law), but the current
is often the part that shows the problem... not the voltage reading.
The carbon transmitter in the phone has been the controlling
factor for years, since it needs over 20ma to sound good.
Be Sure to Check Out Our Longitudinal Imbalance Bulletin! Doc.# 504
WHY THERE ARE HIGH LOOP CURRENT PROBLEMS TODAY, AS
OPPOSED TO LOW LOOP CURRENT PROBLEMS IN THE PAST.
WHY THE PHONE COMPANY WON'T DO A THING FOR YOU.
ALL BETS ARE OFF IN VERY RURAL AREAS
FIXING THE HIGH LOOP CURRENT WITH RESISTORS, WHILE SCREWING
UP THE LEVEL ON THE LINE SO THE CUSTOMER CAN'T HEAR.
UNFIXABLE DATA PROBLEMS
MODEM CONNECTION & SPEED PROBLEMS
UNFIXABLE KSU PROBLEMS - EVEN AFTER YOU'VE CHANGED OUT
THE KSU
CROSSTALK AND SQUEALS ON THE LINES
PROBLEMS ON SINGLE LINE STATIONS OFF OF PBXs
HIGH LOOP CURRENT FROM T1 CHANNEL BANKS
HOW TO MEASURE LOOP CURRENT
WHAT YOU SHOULD READ ON THE METER
WHAT YOU CAN DO ABOUT HIGH OR LOW CURRENT
USING LOOP CURRENT ATTENUATORS
THE EFFECTS OF USING 100 OHM RESISTORS ON BOTH LOOP
CURRENT AND CIRCUIT LOSS
A PRIMER ON CIRCUIT LOSS (CAN'T HEAR PROBLEMS)
HOW TO MEASURE CIRCUIT LOSS
WHAT SHOULD YOU READ ON THE METER
WHAT TO DO IF THE LOSS IS TOO GREAT
USING MILLIWATT (1 THOUSAND CYCLE TONE) LINES
You need to read
the whole bulletin!
503
Fix the Unfixable!
Burned Out Key, PBX & Data Equipment

Garbled Data & Modem Won't Connect
Cut-offs & Squealing on Lines
Crosstalk, Echo & Hollow Sounding
Numerous Intermittent Circuit Failures
Off Premise Equipment Problems
Problems on Voice Mail Ports
High Loop Current Problems
are Causing You Service Calls...
and You Don't Even Know It!
>35ma Symptoms Include:
No DIP Switches... No Meter!
Just plug it in, and the loop
current is automatically
reduced to 25ma!
MODULAR LOOP CURRENT
REGULATOR
1 Line
#WAL5S
: $38.95

3 @ $37.95
2 Line
#WAL5T
: $49.95
3 @ $47.95
$34.50
6 @ $32.50
20 @ $31.50
NEW
66 Block Regulator!
Some Symptoms of High Loop Current Include:
Burned Out Key, PBX or Data Equipment
Garbled Data and Modem Failures
Cut-offs & Squealing on Lines
Crosstalk, Echo & Hollow Sounding Lines
Numerous Intermittent Circuit Failures
Off Premise Equipment Problems
Some Symptoms of Low Loop Current Problems:
Poor Voice Transmission Quality & Low Volume
Ghost Rings
Wrong Numbers
Lost Calls During Transfer
Data Loss
Don't Like Using a Meter?
Don't Like Using a Meter?
NEW!
NEW!
LEDs indicate Low, Good, Fair, High
and Extreme Loop Current at the
push of a Button!
Loop Current Tester
Just Bridge it Anywhere
Across the Line!
Only
$35.95
-8.5
-8.5
-8.5
-8.5
-8.5
Circuit Loss Tester
Phone
Line
Butt-Set
Call the 1000 Cycle Tone at the CO
you're working on, Push the Button
and Read the db Circuit Loss on
the Bright Red ½" Tall LED Display!
Tiny, but
Verrry Accurate!
Reads from +10 to -40db.
+10 to -20db is in ½db increments.
-20 to -40db is in 1 db incremements.
$99.95
Circuit Loss Tester
1KC Tone Generator
When you can't get the number for the 1000
Cycle Tone, this is how you find the Circuit Loss!
Do a "Loop Around Test", where you send tone
out one line, and measure it on another.
Just dial the phone number it's connected to.
Answers on the first ring! Hangs up when you do!

Verrry Precise 1004hz tone at 0db, "stutters"
every 10 seconds just like the telco's tone!
1KC Tone Generator
One Button!
$49.95
#TOH7N
$45.95
The CPC Tester will
tell you whether
you're getting the
CPC signal, telling
your system to hang
up.
NO Button!
Line Powered!
Incredibly easy to use! Plug it into the line. Make a
call and have the other end hang up. The top red LED
will flash for the duration of the CPC signal, and one
of the LEDs will light up indicating the length of the
CPC signal.
Line Powered!
NO Button!
Line Powered!
One Button!
Line Powered!
Line In-Use
Indicator
Test Shoe:
$29.95
Deluxe Unit: $69.95
Has In-Use LED,
and a Switch to
open the line
(same as opening
bridging clips).