Linear Power 1502IQ Programming manual

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F O R T H E L O V E O F M U S I C
MODEL 1502IQ©
(1995-MSRP $429.00)
OWNER'S MANUAL AND
INSTALLATION GUIDE
INTRODUCTION
Congratulations on your decision to purchase a LINEAR POWER™ audio
product. Our commitment to grow with the times and meet the demands of the
ever-changing auto-sound market has brought a new change to our existing line.
LINEAR POWER™ is proud to introduce the "IQ" series.
This series of amplifiers offers two new circuitries, which are a must to today's
auto-sound listener.
First is the incorporation of the "Inverted Channel"("I") allowing the amplifier to
be used in a one, two or three channel mode simply by choosing one of the many
external-wiring methods.
Second is the "Quieting Circuit"("Q"). With this circuit, there is no need to
spend additional time or money on expensive outboard "dethumping" modules.
Each amp is internally equipped with an improved circuit to assure total silence
each time the amplifier is turned on and off.
TECHNICAL DESCRIPTION
POWER SUPPLY 1502IQ©:
Self oscillating for reliability and efficiency. The transformer is epoxy dipped for
extreme vibration resistance.
OUTPUT STAGES 1502IQ©:
Transformerless, direct coupled and fully complementary. Output transistors are
high current and low distortion TO-218 Darlington Devices, operating at a
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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fraction of their limitations. Total power dissipation potential of the output
transistors is 500 watts.
PROTECTION:
Our stable amplifier design is made virtually indestructible by three separate
forms of protection. First is an all-new Thermal Protection Circuit, which is
designed to prevent damage from high frequency oscillations or excessive
ambient temperature. The second form of protection protects the amplifier from
short circuits in the installation. The third form of protection guards against
component damage from reversed power connections.
CONSTRUCTION FEATURES:
The infinitely variable input sensitivity controls permits optimal signal matching for
lowest noise and lowest distortion with virtually any source. All components used
are rated for at least 150% of their intended use, and are mounted on double-
sided fiberglass epoxy circuit boards.
QUALITY CONTROL:
In-house construction of critical components like transformers and chassis
pieces, as well as total assembly, allows LINEAR POWER™ to maintain uniform
quality. 100% of the finished units are tested, then burned in for four hours, and
tested again. Amplifiers, which pass these rigorous controls, have truly earned
the LINEAR POWER™ Logo.
INSTRUCTIONS
Read the following instructions through completely. If they appear too
complicated, we recommend that you have an authorized LINEAR POWER™
Dealer perform the installation.
MOUNTING
1. The amplifier will work best if it is kept as cool as possible. Mount in a position
that allows air to flow freely through the fins. Be sure there is ample space above
the amplifier to avoid trapping heated air rising from the amplifier. The amplifier
should not be mounted upside down. Avoid mounting any amplifier in the dash or
on the firewall to avoid noises being radiated directly into the case.
2. Mount your amplifier in a position that allows ample room for gain adjustments,
and the installation, removal and attachment of leads.
3. The case of your amplifier is designed to act as a noise shield. To maintain
this protection, be sure the metal case of the amp does not touch the metal of the
car. Do not remove or damage the rubber grommets, which provide electrical
insulation and vibration isolation.
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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1502IQ©WIRING DIAGRAM
WIRING INSTRUCTIONS
1. Disconnect the negative ground cable from your vehicle's battery before
making any power connections to your amplifier.
2. Connect the negative power wire from the amp to a solid frame member via
bolt or self-tapping screw. This connection must be a clean, unpainted surface.
Always attach the ground wire first when installing the amplifier, and disconnect
the ground last when removing the amp from the system.
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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3. A fuse of proper size must be installed in line with the main power in order to
prevent damage to your wiring. It should be connected to the battery's positive
terminal, or as close to the battery as possible. Use the fuse holder and fuse
provided, and replace only with the same size fuse. The Model 1502IQ©uses an
AGC 30-amp fuse.
WARNING: USE OF OVERSIZE FUSE WILL DAMAGE YOUR AMPLIFIER
4. The other end of the fuse holder should be connected to the positive power
wire from the amplifier. To extend the length of the power lead, use 12 gauge
wire or larger to reduce power loss.
5. The red and white wire acts as an electrical switch to turn the amplifier on and
off. It should be connected to the power antenna lead from the radio. Where no
power antenna lead exists, a source of 12 volts, connected through a toggle
switch, will do. Do not connect the red and white wire directly to a source that will
leave the amplifier permanently on as this will drain the battery.
6. The RCA (Phono) jacks will accommodate either high or low level signals,
ranging from 150 mV to 5 Volts. For low-level signals, always use shielded cable
and avoid routing signal cables in the vicinity of any power wires. The center pin
of the RCA plug is always the positive input connection. With the connector end
of the amplifier facing you, top side up, the connections are LEFT and RIGHT.
OPERATION/ADJUSTMENT
The output of most any car audio equipment will follow a common distortion
curve. This curve will show that the distortion is at its lowest level right before the
amp reaches full rated output. After that point, the distortion increases rapidly to
unusable levels. For any system to operate at minimum distortion with minimum
noise and still reach full power output, the equipment should be aligned to
operate at the same point on the curve at the same time.
In a basic system, using a single amplifier, set the amp gain to minimum, turn the
source unit up until it just starts to distort, then back down slightly. This is the
point where the output of the source is cleanest. Now, bring the gain of the amp
up until it just starts to distort and back down slightly. This will allow the source
and amp to reach maximum usable output at the same time.
BRIDGED MONO OPERATION
The Model 1502IQ©is built with the right channel inverted. This allows the
amplifier to be used in a bridged mono configuration.
These amplifiers are capable of driving 2-ohm mono loads (**4 ohm speaker
impedance**). To use these amplifiers in that configuration, the internal taps
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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must be changed. Removing the faceplate and changing the spade connectors
from the ‘4’ setting to the ‘2’ setting accomplish this.
The wiring for the bridged mono mode is as follows:
With the connector end of the amplifier facing you, top side up, the speaker
terminal block is arranged: LEFT (-); LEFT (+); RIGHT (-); RIGHT (+). The mono
mode uses the LEFT (+) and RIGHT (-) connections. An electronic crossover,
such as the XO3, should be used to limit the frequency range to the input of the
amplifier for best results.
TWO-OHM CAPABILITY
Unplug the two jumper wires near the four large filter capacitors from the lugs
marked 4 ohm and press them firmly back onto lugs marked 2 ohm. This will
allow the amplifier to operate into a 2-ohm load on each channel, or a 4-ohm load
when used in bridged mono mode (**see statement above**). The lugs are
marked 2 for 2-ohm stereo or 4 ohm bridged, and marked 4 for 4-ohm stereo and
8 ohm bridged.
GENERAL TROUBLESHOOTING
NO SOUND
Check all connections. Check main power fuse. Check accessory fuse of your
vehicle. Check to see that +12Vdc is present at the amplifier on the power wire,
and on the red/white remote turn-on wire. Check for a solid ground connection.
Check that the main music source is putting out signal.
BLOWS FUSES
check all connections to be sure no wires are touching each other or the chassis
of the vehicle or any other equipment in your install. Check that your speakers
are in proper working order.
SHUTS OFF
As this amplifier is equipped with thermal and short circuit shut-down electronics,
in the event of high ambient temperature or improper speaker impedances, the
amp will turn itself off. To avoid damage to speakers, turn down the volume while
waiting for the amp to turn itself back on. If this occurs repeatedly, use a fan to
cool the amplifier and check for proper speaker loads and connections.
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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SERVICE OR REPAIR
To obtain modification, service or repair, please contact our ONLY Authorized
LINEAR POWER™ Product Service Center:
T.I.P.S. INC.
3455 Lanell lane, Pearl, MS 39208
[phone]
E-mail: [email protected]
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© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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SPECIFICATIONS
1502IQ©
Power output @ 4 ohms RMS @ 12.5 volts 75X2
THD @ full output 20-20KHz .05%
Slew Rate volts/microsecond 8Vms
Damping factor @ 4 ohms >100
Channel separation >70dB
Maximum current
4 ohms 18A
2 ohms 23A
Idle .7A
Fuse rating 25A
Dimensions 2x7.7x9.6
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© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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