Radio Shack Realistic Duofone 43-278 User manual

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CUSTOM MANUFACTURED FOR RADIO SHACK , A DIVISION OF TANDY C ORPORATION
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The ~EALIShC. DUoFONE Electronic Telephone Amplifier
System offers you many custom-designed features. Its purpose is to
provide "hands-free" telephone conversations at home or office.
Typical applications are -
• Long distance calls where
your whole family can listen and talk
together.
• Conference calls in
your office.
• Lets
you talk on the phone while taking care of the baby, fixing a
meal, etc.
• Taking
dictation on the phone, using the typewriter, check files,
make notes, checking
inventory ...
All while on the phone -leaving your hands free to handle those
important details.
This Telephone Amplifying Device has been approved and registered
for direct connection to the phone lines. The registration number and
ringer equivalence number
are noted on the DUoFONE label.
It's simple to use and will soon become an invaluable addition to your
office or household. Spend a few minutes learning about your
DUoFONE from this booklet and you'll be sure to enjoy many years of
convenience and dependability.
This telephone product is warranted against manufacturing defects in material and
workmanship for one
(1) year from the date of purchase from Radio Shack company owned
stores and authorized Radio Shack franchisees and d
ea lers. Within thi s period Radio Shack
will repair the telephone product without charge for parts and lab
or. Simply bring your
Radio Shack sales slip as proof-of-purchase date
to any Radio Shack store.
This warranty does not cover damage or failure caused by or attributable to Acts
of God,
abuse, misuse, improper or abnormal usage, faulty installation, improper maintenance,
lightning or other incidence
of excessive voltage or any repairs other than those provided by
a Radio Shack Authorized Service Facility, or transportation costs.
Radio Shack is not responsible or liable for indirect, special, or consequential
damages arising out of
or in connection with the use or performance of the product
or other damages with respect to any economic loss, loss of property, loss of
revenues
or profit, or costs of removal, installation or reinstallation.
Except as provided herein, Radio Shack makes no express warranties, and any
Implied warranty of merchantability or fitness for a particular purpose
Is limited in its
duration to the duration of the written limited warranties set forth herein. Some states
do not allow the limitation or exclusion
of incidental or consequential damages and some
states do not allow limitation
or exclusion of implied warranties; therefore, the aforesaid
limitation(s) or exclusion(s) may not apply
to the purchaser.
There will be charges rendered for repairs to the product made after the expiration
of the
aforesaid one
(1) year warranty period.
This warranty gives you specific legal rights and you may have other rights whi ch vary fr om state to state.
We Service What We Sell
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IMPORTANT NOTE: Before you make connection, you must notify
your local Telephone Company of the registration number and ringer
equivalence number of your DUoFONE. You'll find these numbers on
the label on the bottom of the unit.
The DUoFONE comes with a new mini-modular plug installed on the
end of its cable and a mini-modular jack on the rear cabinet.
Disconnect the mini-mod plug of your phone from the wall outlet and
connect in to the mini-mod jack on the rear of the DUoFONE. Connect
the DUoFONE's mini-mod plug to the wall outlet.
With this connection arrangement you can use either the DUoFONE or
the phone in the normal manner.
If your telephone uses the older type 4-prong receptacles, Radio Shack
sells
the modular-to-4-prong adapter that is necessary to make the con-
version. If your telephone unit is wired directly to the wall, you will
need to update the unit for modular plug and jack connections. The
telephone company will update your wiring .
Note: Your local phone company is authorized to charge you for the
installation of any such jacks. They may ask for the U.S.O.C.
number for the plug connection; this number is RJ-11C (ask for
RJ-11W if you want the wall-type jack).
The DUoFONE must not be connected to:
• Coin-operated phones
• Party-line phones
Now your DUoFONE is ready to use.
To Phone Line
From Telephone - 3 -
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CONTROLS
AMPLIFIER Push Button --- --~
SENSITIVITY Pu,h Button ' ·
PRIVACY Push Button
7
.. I
Speaker ------
(behind grille)
GETTING TO KNOW YOUR DUoFONE
Microphone
(behind grille)
There are just four controls -PRIVACY, AMPLIFIER, VOLUME and
SENSITIVITY.
AMPLIFIER Push Button -press down till it locks in place; this turns
the DUoFONE "on" and connects it to the phone line. This is similar to
picking up the phone to talk. To "disconnect" the DUoFONE and turn
it "off" press this button once again.
VOLUME Control -rotate toward the right (clockwise) to increase
sound
output from the speaker. You should use only enough volume to
hear comfortably; too much may cause distortion. The volume level
will depend on room acoustics and phone line conditions. Hard bare
walls and
tile floors and a fairly empty room will require less volume
than one
with carpeting and drapes.
NOTE:
The VOLUME control has no effect on the signal going into the
phone line.
The level of that signal is controlled electronically.
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SENSITIVITY Push Button - controls the pick-up sensitivity of the
built-in mic. To reduce sensitivity, press down so it locks; to return to
normal sensitivity, press again.
The
MINimum position (down) is the most useful when operating in an
area where there is a high background noise (which has the effect of
locking your DUoFONE "on" and so you could not hear the other
party's voice). See further explanation and uses later on.
PRIVACY Push Button -press down till it locks in place; this turns
the built-in mic "OFF" and the person on the other end of the line
cannot hear
you, but you can still hear him. To return to normal
operation, press again.
The Microphone and Speaker are mounted next to each other behind
the
front panel. When you talk, direct your voice toward the
DUoFONE, so the microphone will pick up your voice.
You hear the incoming portion of the phone call from the Speaker.
SELECTING A LOCATION
In selecting a location for your DUoFONE, you need to know that
room acoustics (with respect to the unit) has a great effect on proper
operation.
You may have to experiment a little with the placement of the unit till
you achieve a location that provides good mic pickup and yet gives
good sound
projection from the speaker.
Also, any
vibration or noise in or near the surface on which you have
placed the
unit may be picked up by the mic and cause unusual sound
effects and
amplifier action. Avoid locations with high background
noise levels.
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OPERATION
RECEIVING A PHONE CALL
When the phone rings, no need to pick up the phone, just press the
AMPLIFIER push button and release.
Adjust VOLUME as desired.
If there is a high background noise level (loud fan, appliance, loud
music or other conversations), the DUoFONE may not switch to
receive - you won't hear the other party's responses - if th is happens,
press SENSITIVITY down or temporarily press PRIVACY down (this
removes the built -in Mic from the circuit, but the DUoFONE stays in
the Receive mode). For most surroundings and applications, you will
be able to l ea ve the SENSITIVITY push button up (for maximum Mic
sensitivity).
NOTE: Just to make sure you understand this point - your DUoFONE
is one way at a time. Both ends of a phone conversation can not talk at
the same time.
You each have to take turns - just like with a CB
Transceiver.
TO PLACE A CALL
Leave AMPLIFIER push button in the OFF position (up) and dial the
phone number as usual. With the phone still off the hook or cradle,
press AMPLIFIER down (ON) and then hang up the phone. Now,
you'r e ready for hands-free convers ation .
TO END A CALL
When you finish your conversation, press and release the AMPLI Fl ER
push button. This breaks the circuit just as when you hand up the
phone -and turns the DUoFONE off.
NOTES ON OPERATION
Always speak in a clear voice and a little slower than with normal tele-
phone use. People at a distance from the DUoFONE should speak a
little louder.
When and how to use the SENSITIVITY switch:
If you operate the DUoFONE in areas with high background noise
levels, it may not function as you would expect. The problem is that
the high volume of the background noise will not allow the other party
to activate the DUoFONE. Remember this basic fact -the party that
speaks first has priority. The electronics circuitry "locks-in" to amplify
that party's voice; for the 2nd party to take over, the 2nd party must
wait for a break in the 1st party's speech. Let's be specific. You are the
1st party; you want to talk to the 2nd party - but if there is a high
noise level
around you, even when you stop talking, the noise is picked
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up by the Mic and keeps the DUoFONE active for "transmit" from
your end. The 2nd party can not be heard (he or she may be talking,
but you won't hear anything).
To solve this problem, we've added the SENSITIVITY switch. When
you press it down (MIN), the Mic sensitivity is reduced, so the circuitry
can "un-lock" and allow the 2nd party to talk. When you use the MIN
position, the background noise will not affect the circuit as much as
before, so when you stop talking, the circuitry can receive the 2nd
party's voice.
When
you use MIN position, a higher sound level is needed to "lock-
in" your voice; so you should speak louder and move closer to the
DUoFONE when using MIN. Also, you should move the DUoFONE
so it won't be subjected to high background noise (or close a door, etc.,
to cut out the noise).
If you get into a situation where the background noise is just too loud
and the DUoFONE gets Jocked into the transmit mode, the best thing
you can do is just pick up the phone and then disconnect the
DUoFONE by pressing the AMPLIFIER push-button. Then use the
phone as normal. (Conditions just are not suitable for a telephone
amplifier system.)
In a conference
situation, remember that the other party can only Iisten
to one voice at a time - so let each speak in turn (one at a time). Also,
keep in
mind that with SENSITIVITY in MIN position, sound pick-up
will not be as sensitive - so either keep noise down to a minimum (in-
cluding side conversations)
or each one should speak up a little more.
How to use PRIVACY switch:
When talking on an ordinary phone, you would cover the mouthpiece
with your hand when you don't want your caller to hear you. With the
DUoFONE, you can do the same thing just by pressing the PRIVACY
switch. This disconnects the built-in Microphone circuit; the DUoFONE
stays in the Receive mode, but no sound is transmitted over the phone
lines.
To be return to normal function, press PRIVACY once more to
release it.
Another practical use of this switch is when background noise around
you gets so loud that it interferes with the DUoFONE's operation, press
the PRIVACY switch. This will prevent background noises from causing
the DUoFONE to go into transmit mode. (This would be similar to a
situation where
you cover your phone's mouthpiece to avoid all the
noise interfering with your caller.) Of course this is only a temporary
solution, but it can be helpful to remember it.
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MORE ON INSTALLATION
Since your DUoFONE has been approved and registered for direct con-
nection
to the phone lines, you can make the connections yourself -
but you must notify the phone company of the registration number
and ringer equivalence number, noted on the label of your DUoFONE,
prior to use.
NOTE: Your DUoFONE must not be connected to party lines or coin
operated telephone lines.
The simplest installation is with the connector supplied. It can be
plugged directly into the new style mini-modular connectors the phone
company now uses. If you need other style plugs or jacks for easy con-
nection,
your Radio Shack store has a complete selection of such jacks
and plugs.
FCC wants you to know .....
It is almost unlikely, but ... if your DUoFONE should cause problems
on
the phone line, the phone company has the right to temporarily dis-
continue your service.
If this ever happens, the phone company will notify you and give you
the opportunity to correct such problem.
Also,
you need to know that the phone company does have the right
to make changes to their lines and/or equipment. If these changes might
affect your DUoFONE (or require changes in the DUoFONE or its con-
nection),
the phone company will notify you in writing so you have a
chance
to take whatever action is necessary to insure uninterrupted
phone service.
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CARE AND MAINTENANCE
Install your DUoFONE near the telephone. Be sure it won't be knocked
off the table, desk, etc. Position the wire free of normal telephone
activities.
The wires should never be routed in a way to interfere with
foot-paths. A foot entangled in the cord could pull out the connection
or knock the DUoFONE to the floor (and maybe damage circuitry).
PROBLEMS?
If the DUoFONE does not work at all (or weakly), check wire connec-
tions
to the phone lines.
Telephone calls are
automatically switched and routed through a
complex group
of equipment. You will occasionally encounter a
"weak" or "noisy" line. In some cases you may have to ask the other
party to speak- up or do so yourself . The connection may be so poor
that you will actually have to re-dial the call. REMEMBER, your tele-
phone amp can
only amplify the signal it receives from the phone line.
Key
or business telephone systems are not an intended use for the
DUoFONE TELEPHONE AMPLIFIER SYSTEM. However, the
DUoFONE can be conected to provide proper operation on many
such systems. Generally,
the TELEPHONE AMP will not provide
adequate switching
capability to cause the telephone company "hold"
circuit to stay disengaged when the telephone handset is "on-hook"
during use of your DUoFONE. We recommend that qualified personnel
make these installations.
We recommend that you avoid placing your DUoFONE under an over-
hang
or any other area with a concave effect. This will help eliminate
"hollow" sounds generated by such a location.
If you do have difficulty with theDUoFONE,or the phones don't work
properly after you have connected it, disconnect the DUoFONE im-
mediately.
Then check to see if the phones work normally ; if they do,
chances are
you've made an error in connection; re-check plugs, jacks
and wires.
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STILL HAVE PROBLEMS - and you've checked all the above ...
1. "When all else fails, read the Instructions." so goes a semi-humorous
bit of advice!
2. Do not use a higher VOLUME setting than is needed for normal
listening. Excessive volume levels may cause distortion.
3. Avoid areas of high background noise (or at least control them).
4. It is normal to have to adjust VOLUME for different calls; phone line
conditions can vary with calls.
5. With any Telephone Amplifying system it is normal to have to talk a
little slower and more clearly than usual - just get used to it.
6. When used in a high noise area, use the Ml N SENSITIVITY position
and speak from a position closer to the DUoFONE (with in about
3'(1m]).
If none of our suggestions help, just bring your DUoFONE to your
local Radio Shack store; we have the personnel, equipment and parts to
properly service your unit.
A Note Of Explanation:
Can't quite figur e out what's going on? How and why the DUoFONE
works as it does? Maybe this will help.
The DUoFONE utilizes a signal-sensing circuit which detects the first
signal applied to the circuitry - either the Mic signal (outgoing) or
phone line signal(incoming)-and turns on the proper internal amplifier
for that signal. That internal amplifier circuit remains on till the signal
ceases. Then the signal-sensing circuit returns to normal and waits for
the next signal. In other words, the party that speaks first has priority
and the second party can not be heard until the first party stops
talking. Then the second party can talk.
A good comparison would be a CB Transceiver -except here we've got
an automatic "send-receive" or Talk switch. But the control is at the
DUoFONE end of the conversation. So, if there is a constant noise in
the room where the DUoFONE is, it will maintain priority and will not
allow the signal-sensing circuit to return to normal. This is why we have
the SENSITIVITY switch - to help overcome this problem.
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4A4
RADIO SHACK, A DIVISION OF TANDY CORPORATION
U.S.A.: FORT WORTH, TEXAS 76102
CANADA: BARRIE, ONTARIO
L4M 4W5
AUSTRALIA
91 KURRAJONG AVENUE
MOUNT DRUITT . N.S.W. 2770
TANDY CORPORATION
U.K.
BILSTON ROAD WEDNESBUR Y
WEST MIDLANDS WS10 7JN
BELGIUM
PARC INDUSTRIEL DE NANINNE
5140 NANINNE
Printed in Korea
811003321B
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