Lectrosonics PP25 User Manual

Voice Projector

Plus Power 25

®

OPERATING INSTRUCTIONS

and trouble-shooting guide

LECTROSONICS, INC.

Rio Rancho, NM

INTRODUCTION

The Plus Power 25 Extension Speaker is designed to
provide virtually unlimited additional sound coverage
when operated in conjunction with any of the Voice
Projector® family of portable sound systems and micro­phone mixers. In addition, it is intended to offer an easy
method of providing additional audience coverage when
used to amplify the high level remote speaker output
from tape cassette players, sound motion picture projec­tors, video tape players, etc. The Plus Power 25 is
completely portable and each unit contains its own
amplifier and power pack as well as the speaker and
enclosure. It weighs less than 6 pounds and is intended
for situations requiring moderate sound reinforcement,
primarily in indoor applications.

The Plus Power 25 may be connected to any Voice
Projector unit by means of an audio extension cable.
Each Plus Power unit has both an input and output
connector, permitting units to be connected in series.
While both the total number of Plus Power extension
speakers and the total length of audio extension cables
which may be driven by a Voice Projector unit are
virtually unlimited, some deterioration of the higher
frequency components may be noticed in installations
exceeding fifteen Plus Power speakers or driving cables
whose total length is in excess of 2500 feet.

AUDIO EXTENSION CABLES

Audio extension cables used with the Plus Power family
of extension speakers must be made from a high quality,
shielded, 2-conductor cable, such as Belden 8412. One
end of the cable must be terminated with a 3-pin female
audio connector (Switchcraft A3F or equivalent) and the
other with a 3-pin mal audio connector (Switchcraft A3M
or equivalent). The cable shield must be connected to
Pin 1 on each connector with the two signal wires
connected to Pins 2 and 3 respectively.

Audio extension cables specifically designed for use with
Plus Power extension speakers are available in standard
lengths of 25’, 50’, and 100’ (CP-25, CP-50 and CP-100
cables, respectfully) from your local dealer or from
Lectrosonics, Inc. In addition a special “Y” adapter cable
is available for use in applications where two or more
Plus Power speakers are to be located in opposite
directions from the driving unit.

OPERATING CONTROLS

The Plus Power 25 extension speaker has only a single
operating control, a four position Volume Range Selector
switch. This control is located on the same panel as the
Plus Power input (female) and output (male) connectors.
All other control functions are provided by the Voice
Projector unit driving the Plus Power 25.

The Volume Range Selector provides four separate
settings for adjusting the sound output level relative to
the volume of the driving unit. To select the appropriate
position, the user should first set the Volume Range
Selector to the minimum (counter clockwise) position
and check the sound level while operating the driving
unit with its volume control at mid-range. If additional
sound coverage is required, the Volume Range Selector
should be advanced (moved clockwise) step-by-step until
the desired sound coverage is achieved. The Volume
Range Selector should always be set at the minimum
level providing adequate sound coverage since higher
volume settings than necessary often tend to decrease,
rather than increase, intelligibility of the speaker. The
Volume Control on the driving unit provides the master
gain adjustment for both the driving unit and all Plus
Power extension speakers connected to that unit.

When the Plus Power 25 is driven by a Voice Projector
unit a relay located within the Plus Power 25 is remotely
activated by a special signal which is supplied by the
driving unit via the audio extension cable. In this mode
of operation the Plus Power 25 will be turned ON when,

and only when

, the driving unit is turned on. This feature
provides the user with a single master On/Off control for
a multiunit sound system composed of the driving unit
and one or more Plus Power extension speakers.

When the Plus Power 25 is used as an auxiliary amplifier
for the output from a tape cassette player, sound motion
picture projector, etc. the high level remote speaker input
must be connected to the Plus Power 25 via the HI
LEVEL IN jack located on the control panel of the unit.
In this mode of operation the Plus Power 25 will be
turned on whenever a phone plug is inserted into the HI
LEVEL IN jack.

2

POWER PACK REPLACEMENT

As the J-7 Power Pack in the Plus Power 25 nears the
end of its useful life, its output voltage will begin to drop,
causing the Plus Power 25 sound to become increas­ingly distorted. Whenever this distortion becomes
noticeable the power pack should be replaced. If there is
no sound output, check all power pack connections
before returning the unit for repair.

Voice Projector Extension Speaker

Regardless of frequency of use the J-7 Power Pack
should be replaced every 12 months to insure satisfac­tory performance. If the Plus Power 25 is to be stored in
excess of 12 months, the power pack should be removed
before storing.

Access to the power pack in the Plus Power 25 unit is
obtained by removing two screws which retain the back
cover. Once this cover is off, the power pack may be
readily removed and replaced. Before reinstalling the
cover, make sure that the power cord plug is properly
seated. Replacement power packs may be obtained
from your local dealer or from Lectrosonics, Inc.

ACCESSORIES

A J-27 heavy duty power pack can readily be installed in
place of the usual power pack. This power pack offers
both additional operating life and an extended storage
life of 3-4 years, as compared to 12-18 months for the J­7 power pack.

An AC power converter which operates on conventional
115VAC current is available for the Plus Power 25
extension speaker. The J-47 Power Converter may be
readily installed in place of the J-7 power pack provided
with the Plus Power 25.

Audio extension cables, which are described elsewhere
in these instructions, are available for interconnecting the
Plus Power 25 with the driving unit and with other Plus
Power units.

Rio Rancho, NM – USA

3

Voice Projector Model PP25

REPLACEMENT PARTS LIST

Part Number Schematic Reference Description

A3012 None PP-25 Amplifier Assembly

15002 C1 Capacitor, 0.15uf/25v

15006 C4 Capacitor, 150pf, disc

15007 C5, C6 Capacitor, 50uf/25v

15001 C7 Capacitor, 100uf/25v

48003 CR1, CR2 Diode, D1300A or 1N3754

48002 CR3 Diode, 1N914

48102 Q3, Q4 Transistor, 2N5356

48105M Q5, Q7 Transistor, 2N3613 or KT1231 w/Hardware

48107 Q6 Transistor, 2N697

51002 K1 Relay, DPDT

A5001 T1 Audio Transformer

Various R7, R8, R10-R16 Resistor, 1/2W, Various Values +/-10%

21004 J1 Octal Socket

21121 J2 Female Audio Connector, 3-pin

21241M J3 Phone Jack & Switch w/Hardware

21235 J4 Phone Jack w/Hardware

21122 P1 Octal Plug

21223 P2 Power Pack Connector Cord

21115 P3 Male Audio Connector, 3-pin

51003M S1 Switch, 4-position w/hardware

Various R4-R6 Resistor, 1/2W, Various Values +/-10%

13001 LS1 Coaxial 6” Speaker

14030 None Black Rubber Foot

14195 None Handle, Black Plastic, Fixed

14010 None Handle, Black Plastic (Old Style)

14012 None Handle Bracket (Old Style)

14013 None Clip-on Cover for Handle Bracket (Old Style)

J-27 None 22.5v Power Pack, (Heavy Duty) Alkaline

4

Voice Projector Extension Speaker

Rio Rancho, NM – USA

5

SERVICE AND REPAIR

If your system malfunctions, you should attempt to correct or isolate the trouble before concluding that the equipment
needs repair. Make sure you have followed the setup procedure and operating instructions. Check out the intercon­necting cords and then go through the TROUBLE SHOOTING section in the manual

We strongly recommend that you do not try to repair the equipment yourself and do not have the local repair shop
attempt anything other than the simplest repair. If the repair is more complicated than a broken wire or loose con­nection, send the unit to the factory for repair and service. Don’t attempt to adjust any controls inside the units.
Once set at the factory, the various controls and trimmers do not drift with age or vibration and never require read­justment. There are no adjustments inside that will make a malfunctioning unit start working.

LECTROSONICS’ service department is equipped and staffed to quickly repair your equipment. In warranty repairs
are made at no charge in accordance with the terms of the warranty. Out of warranty repairs are charged at a
modest flat rate plus parts and shipping. Since it takes almost as much time and effort to determine what is wrong
as it does to make the repair, there is a charge for an exact quotation. We will be happy to quote approximate
charges by phone for out of warranty repairs.

RETURNING UNITS FOR REPAIR

You will save yourself time and trouble if you will follow the steps below:

A. DO NOT return equipment to the factory for repair without first contacting us by letter or by phone. We need to
know the nature of the problem, the model number and the serial number of the equipment. We also need a phone
number where you can be reached 8 am to 4 pm (Mountain Standard Time).

B. After receiving your request, we will issue you a return authorization number (R.A.). This number will help speed
your repair through our receiving and repair departments. The return authorization number must be clearly shown
on the outside of the shipping container.

C. Pack the equipment carefully and ship to us, shipping costs prepaid. If necessary, we can provide you with the
proper packing materials. UPS is usually the best way to ship the units. Heavy units should be “double-boxed” for
safe transport.

D. We also strongly recommend that you insure the equipment, since we cannot be responsible for loss of or damage
to equipment that you ship. Of course, we insure the equipment when we ship it back to you.

Mailing address: Shipping address: Telephones:

Lectrosonics, Inc. Lectrosonics, Inc. Regular: [phone]
PO Box 15900 581 Laser Rd. Toll Free [phone]
Rio Rancho, NM 87174 Rio Rancho, NM 87124 FAX: [phone]
USA USA

We b : http://www.lectrosonics.com Email: [e-mail]

May 2, 2001