Yorkville Sound 3400 User Manual
3
Manual-Service-AP3400-00-1v6.pdf
HIGH EFFICIENCY STEREO POWER AMPLIFIER
400
WORLD HEADQUARTERS
CANADA
Yorkville Sound
550 Granite Court
Pickering, Ontario
L1W-3Y8 CANADA
Voice: (905) 837-8481
Fax: (905) 837-8746
Quality and Innovation Since 1963
U.S.A.
Yorkville Sound Inc.
4625 Witmer Industrial Estate
Niagara Falls, New York
14305 USA
Voice: (716) 297-2920
Fax: (716) 297-3689
SERVICE MANUAL
Printed in Canada
IMPORTANT SAFETY INSTRUCTIONS
This lightning flash with arrowhead symbol,
within an equilateral triangle, is intended to alert
the user to the presence of uninsulated
“dangerous voltage” within the product’s enclosure
that may be of sufficient magnitude to constitute a risk of
electric shock to persons.
Ce symbole d’éclair avec tête de flèche dans un triangle
équilatéral est prévu pour alerter l’utilisateur de la présence
d’un « voltage dangereux » non-isolé à proximité de l’enceinte
du produit qui pourrait être d’ampleur suffisante pour présenter
un risque de choque électrique.
S2125A
FOLLOW ALL INSTRUCTIONS SUIVEZ TOUTES LES INSTRUCTIONS
Instructions pertaining to a risk of fire,
electric shock, or injury to a person
CAUTION: TO REDUCE THE RISK OF ELECTRIC
SHOCK, DO NOT REMOVE COVER (OR BACK).
NO USER SERVICEABLE PARTS INSIDE.
REFER SERVICING TO QUALIFIED
SERVICE PERSONNEL.
Read Instructions: The Owner’s Manual should be read and
understood before operation of your unit. Please, save these instructions for future reference and heed all warnings.
Clean only with dry cloth.
Packaging: Keep the box and packaging materials, in case the unit
needs to be returned for service.
Warning: To reduce the risk or fire or electric shock, do not expose
this apparatus to rain or moisture. Do not use this apparatus near water!
Warning: When using electric products, basic precautions should
always be followed, including the following:
Power Sources
Your unit should be connected to a power source only of the voltage specified in the
owners manual or as marked on the unit. This unit has a polarized plug. Do not use
with an extension cord or receptacle unless the plug can be fully inserted. Precautions should be taken so that the grounding scheme on the unit is not defeated.
Hazards
Do not place this product on an unstable cart, stand, tripod, bracket or table. The
product may fall, causing serious personal injury and serious damage to the product.
Use only with cart, stand, tripod, bracket, or table recommended by the manufacturer
or sold with the product. Follow the manufacturer’s instructions when installing the
product and use mounting accessories recommended by the manufacturer.
The apparatus should not be exposed to dripping or splashing water; no objects
filled with liquids should be placed on the apparatus.
Terminals marked with the “lightning bolt” are hazardous live; the external wiring
connected to these terminals require installation by an instructed person or the use of
ready made leads or cords.
Ensure that proper ventilation is provided around the appliance. Do not install near
any heat sources such as radiators, heat registers, stoves, or other apparatus
(including amplifiers) that produce heat.
No naked flame sources, such as lighted candles, should be placed on the apparatus.
Power Cord
Do not defeat the safety purpose of the polarized or grounding-type plug. A polarized plug
has two blades with one wider than the other. A grounding type plug has two blades and a
third grounding prong. The wide blade or the third prong are provided for your safety. If the
provided plug does not fit into your outlet, consult an electrician for replacement of the
obsolete outlet. The AC supply cord should be routed so that it is unlikely that it will be
damaged. If the AC supply cord is damaged DO NOT OPERATE THE UNIT.
Unplug this apparatus during lightning storms or when unused for long periods of time.
Service
The unit should be serviced only by qualified service personnel.
safety-4v5.eps • April 3/2007
The exclamation point within an equilatereal
triangle is intended to alert the user to the
presence of important operating and
maintenance (servicing) instructions in the
literature accompanying the appliance.
Le point d’exclamation à l’intérieur d’un triangle équilatéral
est prévu pour alerter l’utilisateur de la présence
d’instructions importantes dans la littérature accompagnant l’appareil en ce qui concerne l’opération et la
maintenance de cet appareil.
Instructions relatives au risque de feu,
choc électrique, ou blessures aux personnes
AVIS: AFIN DE REDUIRE LES RISQUE DE CHOC
ELECTRIQUE, N’ENLEVEZ PAS LE COUVERT (OU LE
PANNEAU ARRIERE) NE CONTIENT AUCUNE PIECE
REPARABLE PAR L’UTILISATEUR.
CONSULTEZ UN TECHNICIEN QUALIFIE
POUR L’ENTRETIENT
Veuillez Lire le Manuel: Il contient des informations qui devraient
êtres comprises avant l’opération de votre appareil. Conservez.
Gardez S.V.P. ces instructions pour consultations ultérieures et
observez tous les avertissements.
Nettoyez seulement avec le tissu sec.
Emballage: Conservez la boite au cas ou l’appareil devait être
retourner pour réparation.
Avertissement: Pour réduire le risque de feu ou la décharge
électrique, n'exposez pas cet appareil à la pluie ou à l'humidité.
N’utilisez pas cet appareil près de l’eau!
Attention: Lors de l’utilisation de produits électrique, assurez-vous
d’adhérer à des précautions de bases incluant celle qui suivent:
Alimentation
L’appareil ne doit être branché qu’à une source d’alimentation correspondant au
voltage spécifié dans le manuel ou tel qu’indiqué sur l’appareil. Cet appareil est
équipé d’une prise d’alimentation polarisée. Ne pas utiliser cet appareil avec un
cordon de raccordement à moins qu’il soit possible d’insérer complètement les trois
lames. Des précautions doivent êtres prises afin d’eviter que le système de mise à la
terre de l’appareil ne soit désengagé.
Risque
Ne pas placer cet appareil sur un chariot, un support, un trépied ou une table instables.
L’appareil pourrait tomber et blesser quelqu’un ou subir des dommages importants.
Utiliser seulement un chariot, un support, un trépied ou une table recommandés par le
fabricant ou vendus avec le produit. Suivre les instructions du fabricant pour installer
l’appareil et utiliser les accessoires recommandés par le fabricant.
Il convient de ne pas placer sur l’appareil de sources de flammes nues, telles que
des bougies allumées.
L’appeil ne doit pas être exposé à des égouttements d’eau ou des éclaboussures
et qu’aucun objet rempli de liquide tel que des vases ne doit être placé sur l’appareil.
Assurez que lappareil est fourni de la propre ventilation. Ne procédez pas à
l’installation près de source de chaleur tels que radiateurs, registre de chaleur, fours
ou autres appareils (incluant les amplificateurs) qui produisent de la chaleur.
Les dispositifs marqués d’une symbole “d’éclair” sont des parties dangereuses
au toucher et que les câblages extérieurs connectés à ces dispositifs de
connection extérieure doivent être effectivés par un opérateur formé ou en utilisant
des cordons déjà préparés.
Cordon d’Alimentation
Ne pas enlever le dispositif de sécurité sur la prise polarisée ou la prise avec tige de
mise à la masse du cordon d’alimentation. Une prise polarisée dispose de deux
lames dont une plus large que l’autre. Une prise avec tige de mise à la masse
dispose de deux lames en plus d’une troisième tige qui connecte à la masse. La
lame plus large ou la tige de mise à la masse est prévu pour votre sécurité. La prise
murale est désuète si elle n’est pas conçue pour accepter ce type de prise avec
dispositif de sécurité. Dans ce cas, contactez un électricien pour faire remplacer la
prise murale. Évitez d’endommager le cordon d’alimentation. N’UTILISEZ PAS
L’APPAREIL si le cordon d’alimentation est endommagé.
Débranchez cet appareil durant les orages ou si inutilisé pendant de longues périodes.
Service
Consultez un technicien qualifié pour l’entretien de votre appareil.
AUDIOPRO AP-3400 SERVICE MANUAL
M1012A “THE INPUT BOARD”
The input board processes the audio signal from the input jacks to the voltage amplifier board, (M1011A).
Each channel consists of a balanced gain stage, defeatable bass boost filter, and a preemphasis filter network.
The balanced input, (XLR Jack) and unbalanced input (phone jack) are wired in parallel to the input of a balanced
operational amplifier, (U1). The gain of this stage is 1.6 (4dB) balanced and 1.6 (4dB) unbalanced. Resistors R1, R5
along with capacitors C1 and C2 form a radio interference elimination filter.
Switch S1 selects a flat or bass boosted frequency response. The bass boost filter provides a 20Hz high pass, high Q
filter response with a +4dB peak at 55Hz. The filter consists of a tee network on the input of U1A along with R9, R10,
R11, C5 and C6. The gain is 1 (0dB) in the passband, (above 100Hz).
Operational amplifier U3B is a high pass shelving filter with a +2dB shelf above 20KHz. This filter provides the preemphasis required to obtain a flat frequency response (to 20KHz) on the power amplifier output at full power.
M1011A "VOLTAGE AMPLIFIERS AND SYSTEM CONTROL"
This board contains:
• Voltage amplifiers to drive the current amplifiers on the M1002A boards.
• The front panel volume control circuitry.
• The EMS control system with its associated circuits: Pre clipping and line current sensing heater circuits.
• Clip and activity LED's. Driver circuitry for the amplifier disable relay (used during amplifier turn on, turn off,
thermal shutdown and current limiting).
Circuit Explanation:
Refer to the schematic of M1011A as the sections of the circuit are explained.
The audio signal enters the board from M1012A through connector MS4. The two channels are marked "L" and "R"
for left and right. The signals are to be considered as differential sources and therefore are marked as L+, L-,R+ and
R-. Since the left channel has the same topology as the right channel we will only look at the left channel.
The signal ("L+") at the terminal block (MS4) passes through the front panel level control (P1) and the desired level
enters the inverting input of U1.
Op amp U1 is an inverting amplifier with a set gain of 2.40 (7.6dB). Built around U1 is a dual purpose circuit controlled
by a voltage divider consisting of R15, R16, R17, R18, R19, R20 and R21. The voltage divider sets two reference
levels, (HDRM & CLP). Reference voltage levels vary with the voltage levels on the +/-144VDC supply rails. As the
amplifier?s output is loaded, the supply rails voltage decreases and so do the reference levels.
Transistors Q1, Q3 the surrounding resistors provide a pre-clipping function that tracks the supply rails through the
HDRM voltage reference and clips the audio signal at approximately 11.2V pk. The clip LED indicator circuit is
connected through D1 and D2 to the output of U1, The bases of Q2 and Q4 are connected to the “CLP” reference
voltage, and when the peak output voltage of U1 (+/-Vp) is enough to forward bias the transistor junctions, Q2 or Q4
will trigger the clip led circuit (Q5), and illuminate the clip LED.
The audio signal on the output of U1 enters U3 through R43 and RV1. Under normal operating conditions the gain of
U3 is 1(0dB). The signal then passes through U2 to the voltage amplifier.
1
VOLTAGE AMPLIFIER:
The voltage amplifier amplifies the audio signal?s voltage from 4.8 volts peak (at the output of U2) to approximently
97v peak which is required to drive the current amplifier board M1002A. M1002A provides the current required for the
97v peak signal to drive 1200 watts into 4 ohms out of the binding posts.
Before the circuit is described in detail here is a quick rundown on the signal?s path through the voltage amplifier
stage. Refer to the schematic of M1011A. Let's consider that a positive going AC signal is present @ test point 3. The
positive going signal will turn on the positive side of the voltage amplifier. The signal at test point 3 turns on Q12
(through R40, D14 and D13). The collector of Q12 pulls down on the base of Q14, turns this transistor on further and
allows a greater current to flow out of Q14?s collector. This increase in current passes through Q15 and it?s collector to
emitter voltage drop decreases. The collector of Q15 now being more positive in voltage turns the base of Q18 on
causing an increase in Q18?s collector current resulting in test point 5 going positive.
As the positive side of the amplifier was turning on the negative side would have been turning off. This is how test
point 5 was able to move positive following the input signal. The reverse would hold true if a negative going signal was
present on the input of the voltage amplifier.
CIRCUIT DESCRIPTION:
The voltage amplifier is a mirrored image with circuitry connected to the positive power supply rail being identical (but
opposite polarity) to the circuitry connected to the negative power supply rail.
SHUTDOWN CIRCUIT:
The last circuit on board M1011A is the shutdown relay and its associated drive circuitry. The relay circuit has two
possible operating states.
1. Amplifier on under normal operating conditions.
2. Amplifier power switch has just been turned OFF/ON or the amplfier is in current limit protecting the amplifier?s
output or the amplifier has overheated.
CIRCUIT DESCRIPTION
Here is how the circuit accomplishes these functions. The relay?s normally closed contacts short the output of the
voltage amplifiers to ground when the power switch is off. When the power switch is turned on, the relay remains off
(normally closed) for about 6 seconds. C52 charges to 35V and results in Q37 turning off allowing Q36 to turn on. As
Q36 turns on, it connects the negative terminal of the relay?s coil (Pin 16) to ground energizing the relay and opening
the normally closed contacts.
If prolonged current limiting occurs on the amplifier?s output transistors then D50 or D51 (depending on which channel
is current limiting) will be forward biased turning on Q38 (from its off state). Now +144VDC appears on the collector of
Q38 and through R130 and R128 turn on Q37 therefore turning off Q36 by shorting its base emitter junction. Q36
turning off will turn the relay off and the normally closed contacts (off state) will short the outputs of the voltage
amplifiers to ground so as not to continuously stress the amplifier?s output transistors. A cycle now occurs. With the
voltage amplifiers now disabled there is no signal driving the output transistors (Q14 to Q28) on board M1002A.
For this reason we will look in detail at the positive side of the amplifier.
The audio signal enters the voltage amplifier at test point 3. The signal passes through R40, D14 and D13 to the base
of Q12. Diodes D13 and D14 set up the DC bias on Q12 to approximately 0.6 mA.
The first voltage gain stage consists of Q12 along with the resistor chain on its collector and the emitter resistor (R44).
Transistor Q12 drives the base of Q14 through the resistor chain. A DC current of approximately 6 mA should flow
through the collector of Q14. The voltage drop across Q14 remains constant and is derived from the voltage drop
across the voltage reference Q20, resistor R58, and the base/emitter junction of Q15. This total voltage should equal
approximately 3 VDC. Transistor Q14 is the second gain stage and its output current flows through Q15. Transistor
Q15 is a common base stage with the collector driving the base of output buffer Q18.
Diode D17 is a clamping diode that prevents the maximum peak of the audio signal from coming within 4V of the 144
VDC rail. This is to prevent the output current amplifier (board M1002A) from going into saturation during clipping and
therefore having storage delay problems.
Transistor Q18 buffers the high impedance present on the collector of Q15. The output of the buffer provides a low
output impedance at test point 5 and is current limited to 25mA through the clamping action of D19, D20 and D23.
The signal at TP-5 drives the current amp board M1002A.
DC offset on the amplifier?s output is corrected by operational amplifier U2. The DC offset forms a current through
R54, R14 and is blocked by C5 giving a DC offset correction gain of -1.
The activity L.E.D. function is a simple charge pump circuit with a transistor that redirects a constant current path
through the activity L.E.D.
The current limit circuit on M1002A turns off and D50 and/or D51 are not forward biased and Q38 turns off. Through
Q37 and Q36 the relay is turned back on and the voltage amplifiers are now active again, driving the output
transistors. If current limiting still occurs, then the same cycle will occur. If the cause of current limiting (low impedance
or short on the speaker output terminals) has been removed, then the amplifier will continue to operate normally.
The third operation that the relay provides is "overheat shutdown". If for some reason the fan cannot keep the
heatsinks in a safe operating temperature area then the fan control circuit (on board M1013A) will deliver through the
"kill" signal line a positive current to turn Q37 on and turn Q36 off to turn off the relay and disable the voltage
amplifiers. When the temperature of the amplifier has been cooled down by the fan, then the kill signal will disappear
and the relay circuit will turn on the relay to resume normal operation. Anytime the relay is in the "protect" mode (due
to the abnormal states) then contact pin 8 of the relay will illuminate LD5 (the protect LED on the front panel).
M1002A “CURRENT AMPLIFIER BOARD”
The current amplifier board (M1002A) receives a high voltage audio signal from voltage amplifier board (M1011A) and
provides the current drive necessary to drive speaker cabinets.
The current amplifier is a two tier complimentary output driver design controlled by a complimentary mos-fet stage.
CIRCUIT DESCRIPTION - REFER TO THE SIMPLIFIED SCHEMATIC #1 ON THE FOLLOWING PAGE
2
3
QUIESCENT CONDITION:
This design is class A/B and therefore the output driver transistors must be forward biased to provide low crossover
distortion. In most class A/B designs, a diode chain or VBE multiplier is used to control the bias voltage and provide a
means of adjusting the bias. This design is different as there isn't a diode chain or VBE multiplier. For simplicity lets
consider only the positive side of the current amplifier, that is all parts between the positive power supply rails and the
audio signal output/input terminals. The negative side is the same as the positive, except for polarity changes.
To bias Q14, greater than 0.5V is needed from base to emitter, (or for simplicity from base to amplifier output). Points
A and B are at the same potential, so consider them to be connected. If this is true then 0.5V from test point 2 to the
amplifier output must appear across R12. There must be some way of developing this voltage across R12, and there
is using the mos-fet (Q5) driver along with local feedback.
Simplified schematic Fig. #1 shows the biasing circuit. The current needed to develop 0.5V across R12 comes from
the source of Q5. When the amplifier is first turned on the current source (Q3) turns on Q5 and current flows through
R12 developing a voltage. When this voltage approaches 0.5V Q1 turns on and robs current from the gate of Q5.
This causes Q5 to turn off until the reduced current flowing through Q5 maintains 0.5V across R12. Q1 will turn off
slightly causing Q5 to increase its source current. The circuit reaches a point of equilibrium with approximately 0.5V
across R12.
Because all output devices are not identical and base emitter voltages vary, some adjustment must be available to
slightly adjust the 0.5V across R12. This is accomplished with RT1. RT1 causes Q1 to turn on slightly more or less
resulting in Q5 turning on slightly more or less and therefore R12? s voltage will be slightly more or less than 0.5v. The
proper quiescent current adjustment is 4mV ( to be measured between test points 8 and 9).
THE SECOND TIER:
Refer to the simplified schematic Fig. #1 while reading the following text. One way of making an amplifier more
efficient is to vary the Power Supply Voltage on the collectors of the output transistors (Q14 & Q22). The lower the
voltage from collector to emitter, the lower the device dissipation. During quiescent conditions, there is 78VDC on the
collectors of output transistors Q14 and Q22. The peak AC voltage that can appear on the amplifier's output is
approximately 132V peak. How can an output transistor deliver a 132V peak when its collector is only at 78VDC? It
can if its collector is pulled up to 144VDC as the output signal's peak rises above 78VDC. (refer to Fig. #2). The
second tier voltage must remain above the amplifier's output voltage by amount Vm. Therefore the circuitry controlling
the second tier voltage must increase the tier voltage before the amplifier's output voltage reaches 78VDC. This
leading voltage is necessary to compensate for time lag of the second tier circuit during fast rising amplifier output
signals.
4 5
The voltage between the
amplifier?s output and test point
4 is approximately 14.7VDC
derived from the voltage drop
across ZD3 @ ZD4. We call this
voltage the “floating battery”
because it floats on top of the
output audio signal w ith point 4
always being 14.7VDC greater
than the peak of the output
signal. Point 4 drives the gate of
mos-fet Q11. Q11 controls the
transistors of the upper tier. As
Q11 turns on it's source foward
biases the base of Q13 and Q13
pulls the collector of Q14
towards the 144 volt rail. The
gate to source voltage needed to
turn on Q11 is approximately 3.5
volts. When the peak output
signal is about 67vp (55v-(14.7v-
3.5v)) then Q11 will start to turn on the second tier. The second tier voltage will remain about 11 volts (Vm) above the
peak of the output signal to the point of clipping where this voltage is reduced to about 4 volts. Zener ZD8 protects the
gate source junction of Q11 and also provides a current path through R29 for the “floating battery”.
Current Limit Protection Circuitry
DC Protection
If a DC voltage greater than 8 volts appears on the output of the amplifier for more than 200 milliseconds then triac
Q30 will turn on holding the output at ground potential. MBS4992 is a device that turns on at either + or - 8 volts DC.
To have an amplifier drive 3000 watts into practically any combination of speaker cabinets and know what is a safe
load and what is not is a very difficult task. An extensive amount of time was spent on the current limit circuitry so that
it may simulate the safe operating area of the output transistors (SOAR curve). No matter how reactive the load may
be the phase shift that it presents, along with it's resistive component is used to set the output current limit of the
output transistor stage.
Refer to the schematic of board M1002A while reading the following text. The current limit circuitry is a mirrored image
with circuitry connected to the positive power supply rail being identical (but opposite polarity) to the circuitry
connected to the negative power supply rail. For this reason we will look at the positive side of the circuitry.
Transistor Q9 measures the peak current flowing through resistor R53. The voltage across R53 (as a result of the
current flowing through it) is scaled down by R55, R35, R36, R37, D7 and D11- these parts make up the safe
operating area along with the time constants of C26, R34, C12 and R26. Fig. #3 shows a waveform of the current that
passes through R52 and R53 when the output of the amplifier is shorted to ground. This can only be seen by using an
oscilloscope to measure differentially across R52 and R53. The conditions of the measurement are contained on the
diagram. During current limit when Q9 turns on it reduces the voltage across R42. R42 is in series with a 16 volt zener
(ZD7) and is also in parallel with the junction of Q8. Q8 is normally saturated by the current that flows through R20,
ZD7, R42, and R22. When Q9 reduces the voltage across ZD9 and R42 to below 16.6 volts then Q8 turns off allowing
a charge to build up on C8 through resistors R24 and R25. If current limiting occurs for a long enough duration to
allow C8 to charge to 1.2 volts then Q7 will turn on tripping the relay circuit on board M1011A. As soon as the relay is
turned off the audio signal will be turned off at the voltage amplifiers and will remain off for about 5 seconds before the
relay turns on and allows the audio signal to pass through the amplifier. If a current limit condition is still present then
the whole cycle will occur again and repeat until the load conditions on the amplifier's output are safe for the amplifier.
When a safe load reappears the amplifier will automatically reset and drive that load (the speaker cabinet).
Subwoofers present large inductive loads to the amplifier and are driven at low frequencies where the large current
peaks must be tolerated for short periods of time. To accomodate this type of loading C26 and R34 are used to retard
the firing of Q9 at low frequencies.
NOTE:
Conditions of test:
A. Pass a 100Hz 25v peak signal through the M1002A board under test with no load connected to the amplifier
output.
B. Connect points 1 and 2 as shown in the diagram. The amplifier should go into protect mode as the triac ( if
working) shorted the output of the amplifier to ground, and the amplifier goes into current limit.
C. Disconnect the triac test circuit and allow the amplifier to complete it?s protect cycle.
D. Reverse connections 1 to 2 and 2 to 1 and test again. The same results as in B) should be observed if the triac is
working.
Only test the triac for one protect cycle as prolon ged testing will heat the triac to a h igh temperature.
Everytime you replace blown output transistors on a M1002A board
test the DC protection triac with the following circuit.
6
7
EMS Circuit
The Energy Management System circuit only applies to North American line voltage products. A North American AC
receptacle can provide 1850 watts before the wall breaker would trip, but how can a amplifier provide 2 x 1200 watts
out when only 1850 watts is avaliable out of the AC receptacle? A sinewave source connected to the amplifier driving
the amplfier to full power output will cause the circuit breaker on the amplifier to trip. Music driving the amplfier to
clipping can be equal an average power output between 12 and 30 percent of the amplifier?s maximum capable power
output. Under this condition less than 12 ampheres of current is drawn from the AC line. Some synthesized music
may go beyond the 12 to 30 percent level and make the amplfier draw more than 12 amperes from the AC line. If this
occurs the coil on board M1013A heats up to the point where through the heating of thermistor RV5, Q32 sinks
current through R109. On board M1011A Q11 starts conducting through the connection to R109. Q11 heats
thermistors RV2 and RV4 attenuating the audio signal going to each amplfier channel, thus decreasing the current
drawn from the AC line to the point where less than 12 ampheres is being drawn.
Fan Circuit
Looking at the schematic to
board M1013A, here is a quick
explaination of the fan control
circuit. There is a thermistor on
each M1002A board. When the
amplifier is first turned on, Q33
is saturated sinking the current
source through ZD10. As either
negative temperature coefficient
thermistor begins to heat up,
more current flows through D38
or D39 decreasing the conductor
of Q33 until the increasing VCE
of Q33 is enough to turn on Q34
and Q35. Further heating of the
thermistor causes an increasing
of Q33?s collector to emitter
voltage. Q34 and Q35 are a
common emitter stage with Q35
providing the drive current for the fan. To lower the dissipation of Q35, D42, D43, ZD12, ZD13 and R118 turn off Q35
when the full wave rectified voltage present of the collector of Q35 reaches approximently 50V by robbing current from
the base of Q34. The maximum fan voltage is 20.5 VDC. ZD14 and R120, R121 and R122 provide a current limiting
function. Figure #4 shows the current throught these resistors when there is 12VDC across the fan.
Identifying Defective Boards in the AP-3400
STEP 1: VISUAL INSPECTION OF FRONT PANEL AND FAN
A. Check to see whether the green power LED is lit. If not, the amplifier has a power supply (M1013A board),
transformer, A.C. switch or line cord problem.
B. If the red protect LED stays on or samples off and on, this usually indicates a problem with one or both of the
M1002A current amplifier modules and possibly damage to the M1011A voltage amplifier board. Check for
misaligned pin connections or see if the ribbon cables have been cut or pinched through their insulation.
C. The fan running at full speed on power up usually indicates a problem with the fan circuitry on the M1013A board,
but it can also be caused by M1011A circuit problems. Erractic fan behaviour can be caused by damaged
thermistors located under the M1002A heatsinks.
D. No output on either or both channels can be caused by intermittent push switches at the input.
STEP 2: VISUAL INSPECTION OF INTERNAL CHASSIS
A. a) After removing the lid, look for any signs of smoke, charring or burnt components. If the M1002A boards have
such damage there may be some damage to the M1011A voltage amp board in the form of blown ICs, or possibly
open or shorted diodes, LED?s, resistors, transistors or capacitors. Exploded electrolytic capacitors indicate you
have major repairs to the M1002A, M1011A and M1013A boards.
Thermal Shutdown Circuit
Test point 7 in the fan circuit is the measuring point for the shutdown voltage. As the temperature sensing thermistors that
control the fan circuit heat up the vol tage on test poin t 7 rise s until at 85 degree s celciu s on the M1002A heat sinks the
voltage on test poi nt 7 rea che s 34.5 V DC an d the am pli fie r must b e shut do wn to pro te ct the outp ut po we r t ran si sto rs . ZD15
and D47 become forwa rd biased and th rough the ki ll conne ction to boa rd M1011A , Q37 on M1011A tu rns on turni ng the
relay off and muting the audio sign al. Afte r the amplifi er cool s down th e kill volta ge will decrease FI GURE #4 AP340 0 Fan
Current Waveform until Q37 turn s off turning the rela y back on enabling the amplifie r.
8
9
STEP 3: POWER UP PROCEDURE WITHOUT M1002A BOARDS
SPECIFICATIONS
It is extremely important that you never power up an AP3400 with the interconnecting cablesbetween the circuit
boards not connected.
Time and possible further damage will be reduced if you test M1011A and M1002A boards separately. To do this you
must use the M1011A and M1002A test connecters. These are shown in figures #5 and #6. These can be made if the
Molex connector parts are available or order them from the Yorkville Service Parts Dept. With the test connectors
connected to every board, slowly variac up the line AC voltage.
NOTE:
It may be simplier to remove the power supply connections to M1002A boards not being troubleshooted to
reduce the possibility of further damage. With the M1011A test connector connected, a sinewave can be passed
through the board and be seen on test points 5 and 6. With the M1002 Atest connector installed, static DC
measurements can be made. A slight DC offset may be present on the board?s output as there will not be any DC
correcting feedback.
STEP 4: DISMANTLING AND REASSEMBLY PRECAUTIONS
A. When removing power supply wires or resoldering wires to eyelets on the M1011A board, double check that there
are no solder bridges or icicles bridging traces or other eyelets. Failure to do so will result in the destruction of
newly installed boards as well as other boards in the unit. Also make sure wire color codes are correctly oriented
in their proper eyelets, and be careful that ribbon cables don?t get pinched or cut under the M1011A board.
B. When reinstalling M1002A boards, make sure the output wires, i.e. the red and yellow signal and black ground
wires, are not reversed. If either or both channels are reversed, the amp will stay in protect mode with the red
protect LED staying on or sampling on and off.
POWER
•
All values are in WATTS at 1KHz, except FTC 20Hz-20KHz.
•
Measurements made with regulated 120 VAC sine wave at line cord.
•
All values are rounded down to the nearest 25 watts
BURST AVERAGE
Measured as a 2 cycle burst at 1KHz, 8:1 duty. (Continuous measurements may require line currents >15 Amps).
ONE CHANNEL DRIVEN (WATTS).
LOAD CONT. AVG. BURST AVG. PEAK INSTANT FTC 20-20KHz
8 ohms 900 1250 3000 800
4 ohms 1500 2250 6000 1200
BOTH CHANNELS DRIVEN (WATTS).
LOAD CONT. AVG. BURST AVG. PEAK INSTANT FTC 20-20KHz
8 ohms 750 1200 3000 650
4 ohms 1200 2175 6000 950
BRIDGED (WATTS)
LOAD CONT. AVG. BURST AVG. PEAK INSTANT FTC 20-20KHz
16 ohms 1500 2400 6000 1300
8 ohms 2400 4350 12000 1900
THD DISTORTION
LOAD AT 1KHz 20Hz - 20KHz
8 ohms <0.003 % <0.04 %
4 ohms <0.004% <0.05 %
CROSSTALK:
INPUT IMPEDANCE:
INPUT SENSITIVITY:
FREQUENCY RESPONSE:
HUM AND NOISE
DC OFFSET:
PROTECTION:
COOLING:
SLEW RATE:
DAMPING FACTOR:
MAX OUTPUT CURRENT:
TURN ON/OFF:
EFFICIENCY:
WEIGHT:
SIZE:
POWER SUPPLY:
POWER COMSUMPTION:
-75 dB below full power at 1KHz
-60 dB below full power, 20Hz - 20KHz
20K ohms balanced, 10 Kohms unbalanced
1.4 VRMS sine wave = full power (36 dB gain).
Within 1dB, 20Hz to 20KHz (50Hz boost sw out)
: -105 dB below max output RMS voltage, unweighted
less than 25 millivolts
fully protected, DC, LOAD and THERMAL
interleaved heatsink with DC servo controlled fan
Power amp: 30 V/usec, 60 V/usec in bridged mode
(rise time limited to 18 V/usec by input filter).
>500, 20Hz - 400Hz, into 8 ohms
100 amperes for 10 milliseconds, 50 amperes continuous
< 15 milliwatts / seconds, 0.5 Wpk (1s on delay).
Better than 75% at full power into 4 ohms
42 pounds 17.75 Kilograms
3.5" x 19" x 15.75" (front panel to binding posts)
Toroidal transformer and combination
power switch/circuit breaker
Will not exceed 13.5 Amps under actual conditions
10
11
Identifying Defective Boards in the AP-3000 & AP-3400
Please note:
STEP 1: VISUAL INSPECTION OF FRONT PANEL AND FAN
a) Check to see whether the green power LED is lit. If not, the amplifier has a power supply (
board), transformer, A.C. switch or line cord problem.
b) If the red protect LED stays on or samples off and on, this usually indicates a problem with one or both
of the
M1002
Note:
M1002
Any of the Molex cables from the
current amplifiers can cause the protect LED to stay on or sample on and off. Check for
misaligned pin connections or see if the ribbon cables have been cut or pinched through their insulation.
c) The fan running at full speed on power up usually indicates a problem with the fan circuitry on the
M1013
board, but it can also be caused by
by damaged thermistors located under the
d) No output on either or both channels can be caused by intermittent push switches at the input.
STEP 2: VISUAL INSPECTION OF INTERNAL CHASSIS
a) After removing the lid, look for any signs of smoke, charring or burnt components. If the
boards have such damage, the
no similar charring on their com ponents. At the least, there will be some dam age to the
amp board in the form of blown ICs, or possibly open or shorted diodes, LEDs, resistor s, transistors or
capacitors. Exploded electrolytic capacitors indicate you have
M1013
boards.
STEP 3: POWER UP PROCEDURE WITHOUT M1002 BOARDS
It is
extremely important
procedure located on the
so will possibly result in damaging a good board. This procedure should only be done on a no load
scoped output to insure the rest of the cir cuit boards are work ing before installing new or repaired
modules. The output of a fully operational
wave form when a patch plug is attached at Pin #1. If the wave form is distorted or non- existent, or there
is DC offset, do not attempt to connect any
the new or repaired
Note: M1002?s
input Molex ribbon to the
STEP 4: DISMANTLING AND REASSEMBLY PRECAUTIONS
a) When removing power supply wires or resoldering wires to eyelets on the
that there are no solder bridges or icicles bridging traces or other eyelets. Failure to do so will res ult in the
destruction of newly installed boards as well as other boards in the unit. Also m ak e s ure wire color codes
are correctly oriented in their proper eyelets, and be careful that ribbon cables don?t get pinched or cut
under the
boards.
b) When reinstalling
ground wires, are not reversed. If either channels or both are reversed, the am p will stay in protect mode
with the red LED staying on or sampling on and off.
All boards used in the AP-3400 are designated with an `A' suffix (e.g. M1002A) and
use bright red solder mask
current amplifier modules and possibly damage to the
M1011
M1002
M1011, M1012
circuit board to the
M1011
circuit problems. Er ratic fan behaviour can be caused
heat sinks.
and
M1013
boards may also be damaged even if there is
M1012
voltage amplifier board.
M1012
input board as well as the
M1011
major
repairs to the
M1002, M1011
that you never power up an AP-3000 or AP-3400 without following the
M1011
M1002
schematic highlighted within the box drawn in dashed lines. Failure to do
M1011
will give a 70V peak to peak sinusoidal (undistor ted)
M1002
module to the
M1011
or you will immediately destroy
and will also cause more damage to the rest of the amplifier.
power supply wires (red, yellow, white, blue and black) must be rem oved as well as the
M1011
when attempting to power up an
M1002
M1011
boards as this will result in shut down into the protect m ode or even destruc tion of m or e
M1002
boards, make sur e the output wires, i.e. the red and yellow signal and black
.
M1011
board, double check
M1013
M1002
voltage
and
M1011
AP3400 Parts List 10/28/98
YS # Description Qty. YS # Description Qty. YS # Description Qty.
6410 GREEN 3MM LED 1V7 5MA BULK BRT CLR 3 5621 470U 63V 20%CAP RADIAL ELECT BULK 1 4854 1/4W 1K2 5% T&R RES 2
6411 RED 3MM LED 1V9 5MA BULK BRIGHT 3 5892 6800U 80V 10%CAP RADIAL ELECT BULK 8 4624 1/2W 1K5 5% T&R RES 1
6419 BRIDGE 35A 400V WIRE LEAD GI3504 2 4522 4K7 TRIM POT 2 4824 1/4W 1K5 5% T&R RES 12
6425 BAV21 200V 0A25 DIODE T&R 6 4400 _10K 25A-AUD/DETENT STYLE"P15"16MM 2 4847 1/4W 2K2 5% T&R RES 2
6438 1N4004 400V 1A0 DIODE T&R 10 3590 12.0 AMP SWITCH BREAKER WHITE 1 4804 1/4W 3K 5% T&R RES 8
6825 1N4148 75V 0A45 DIODE T&R 71 3822 500NH COIL 18AWG 0R000 AIR CORE 1 6124 1/4W 3K 5%MINI T&R RES 2
6934 MR854 400V 3A0 DIODE FAST RECOV 24 3820 4UH COIL 14AWG ZOBEL HORIZONTAL 2 4744 5.0W 3K6 5% BLK RES 8
6439 1N5225B 3V0 0W5 ZENER 5% T&R 4 3464 WIRE TO BOARD CRIMP 18-24 AWGT/LEAD 2 4827 1/4W 4K7 5% T&R RES 7
6440 1N750ARL 4V7 0W5 ZENER 5% T&R 5 3465 WIRE TO BOARD CRIMP 16-18 AWG TIN 4 4982 1/4W 4K7 5%MINI T&R RES 4
6459 1N4732A 4V7 1W0 ZENER 5% T&R 2 3486 CLIP 250X032 22-18AWG DISCO-LOK 14 4778 1/4W 5K36 1% T&R RES 2
6461 1N5240BRL 10V0 0W5 ZENER 5% T&R 1 3489 CLIP 250X032 18-22AWG DISCO/INSL 2 4862 1/4W 5K6 5% T&R RES 2
6450 1N5242B 12V0 0W5 ZENER 5% T&R 4 3490 CLIP 250X032 14-16AWG DISCO/INSL 1 4887 1/4W 7K5 5% T&R RES 11
6822 1N4745A 16V0 1W0 ZENER 5% T&R 4 3682 250 MALE PCB TAB BULK ON CATRIGE 14 4990 1/4W 8K2 5%MINI T&R RES 2
6824 1N5246B 16V0 0W5 ZENER 5% T&R 4 3447 DUAL BINDING POST TPP3 2 4800 1/4W 10K0 1% T&R RES 20
6432 1N5248B 18V0 0W5 ZENER 5% T&R 2 3498 M203-02 PLAIN PC MNT JK SKT 2 4829 1/4W 10K 5% T&R RES 2
6465 1N5250B 20V0 0W5 ZENER 5% T&R 4 3660 FEMALE PC MOUNT XLR NTRX.NC3FPR-H-O 2 4775 1/4W 14K0 1% T&R RES 5
6433 1N5257B 33V0 0W5 ZENER 5% T&R 3 3451 0.089 OD SMALL EYELET ELECTROPLATED 18 4630 1/2W 15K 5% T&R RES 10
5101 BC550C TO92 NPN TRANS. T&R 19 3542 SE44 LARGE EYELET TIN-PLATED BRASS 23 4830 1/4W 15K 5% T&R RES 5
5102 BC560C TO92 PNP TRANS. T&R 10 3630 FAN GUARD METAL 80MM CHROME 1 4771 1/4W 17K8 1% T&R RES 11
5103 MPSA06 TO92 NPN TRANS. T&R 1 3860 FAN 80MM X 80MM 40CFM 12VDC 1 6125 1/4W 18K 5%MINI T&R RES 2
5107 2N5551 TO92 NPN TRANS. T&R 5 3692 HEATSINK THERMALOY 6079-PB 5 4885 1/4W 20K 5% T&R RES 4
5113 MPSA42 TO92 NPN TRANS T&R 4 3893 AAVID HEATSINK 5811B 2 4777 1/4W 21K5 1% T&R RES 2
5114 MPSA92 TO92 PNP TRANS T&R 5 3894 AAVID 5972-B H/S W/TAB B.O. 4 4832 1/4W 22K 5% T&R RES 1
6854 2N6517 TO92 NPN TRANS. 2 3501 B52200F006 COMP WASH #4 SMALL 13 4833 1/4W 27K 5% T&R RES 6
5105 MPSA13 TO92 NPN DARLINGTONT&R 1 3750 VINYL CAP SC 0.500 BLACK 1/2" 1 4840 1/4W 33K 5% T&R RES 6
5106 MPSA63 TO92 PNP DARLINGTONT&R 3 3789 TERMINAL STRIP (BEAU INTERCONNECT) 1 4868 1/4W 36K 5% T&R RES 2
5123 NJM431L TO92 SHUNT REG T&R2V 4 3806 RECTANGULAR WASHER FOR TRANS SUPPRT1 4908 1/4W 45K3 1% T&R RES 1
6456 BF872 TO202 PNP TRANS. 1 8682 #4 TEFLON WASHER .125ID .281OD .031 1 4834 1/4W 47K 5% T&R RES 8
6873 MJE340 TO126 NPN TRANS 2 8498 6-32 X 3/8 STEEL PEM STUD 4 4836 1/4W 68K 5% T&R RES 6
6874 MJE350 TO126 PNP TRANS. 2 8499 6-32X1 STEEL PEM STUD 7 4772 1/4W 82K5 1% T&R RES 6
6891 TIP50 TO220 NPN TRANS 2 3795 #8 GROUND LUG ZIERICK 505-169 3 4898 1/4W 91K 5% T&R RES 4
6893 MJE5730 TO220 PNP TRANS 2 3468 8? 3/16 SJT AC LINE CORD STRIP 17" 1 4838 1/4W 100K 5% T&R RES 4
6779 MJH11018 TO218 NPN DARLINGTON 1 3821 HEYCO #1200 STRAIN RELIEF 1 4776 1/4W 113K 1% T&R RES 2
6911 BDX54C TO220 PNP DARLINGTON 1 3521 SIDE ENTRY PCB CONN .156 8POS 1 4839 1/4W 150K 5% T&R RES 4
6912 BDX53C TO220 NPN DARLINGTON 1 3541 24 PIN BREAKAWAY 90 .156 0.333 4668 2.0W 220K 5%10MM BODY T&R RES 2
6752 MTP10N15L TO220 N CHAN MOSFET 2 3543 20 PIN BRKAWAY 90 LOCK .156 0.75 4841 1/4W 220K 5% T&R RES 3
6923 MTP2P50E TO220 P CHAN MOSFET 4 3593 PCB CONN 90 5 CIR .156 3 6126 1/4W 220K 5%MINI T&R RES 4
6924 MTW10N40E TO247 N CHAN MOSFET 2 8701 4-40 KEPS NUT ZINC 17 4843 1/4W 470K 5% T&R RES 4
6925
MTP8P20 O220 P CHAN MOSFET 2 8793 4-40 HEX NUT ZINC 6 6127 1/4W 470K 5%MINI T&R RES 2
6900 YS6900 (22) TO3 NPN TRANS. 16 8760 6-32 KEPS NUT TIN PLATED 64 4844 1/4W 1M 5% T&R RES 1
6927 YS6927 (23) TO3 PNP TRANS. 16 8800 6-32 KEPS NUT ZINC 28 4797 1/4W 1M2 5% T&R RES 1
6840 MC33078P IC DUAL OP AMP 5 8854 6-32 X 1/4 HEX NUT ZINC 6 4888 1/4W 4M7 5% T&R RES 2
6884 NE5532N IC DUAL OP AMP 1 8787 8-32 KEPS NUT ZINC 3 3699 RELAY 2C 01AMP DC48 ???MA PC-S 1
5190 MBS4992 TO92 8V5 DIAC T&R 2 8797 5/16-18 KEPS NUT SJ500 1 3594 9.5" 5C-24AWG RIBBON HEAVY DUT.100" 3
6444 MAC224-4 TO220 40A TRIAC 200V 2 3797 TO-247 THERMO CONDUCTIVE PAD 3 3595 17" 8C-24AWG RIBBON HEAVY DUT.100" 1
6477 100K 5% 1/4W THERMISTOR T&R 0.2 8 3815 TO3 PREGREASED MICA 56-03-2AP 32 8865 4-40 X 5/16 PAN PH MS SJ500 4
5401 _10P 500V 5%CAP T&R RAD CER.2"NPO 4 3846 TO220 MICA THERMAL CONDUCTOR 56359B 8 8742 4-40 X 3/8 PAN PH TAPTITE JS500 4
5404 _27P 100V 10%CAP T&R TUBULAR NPO 2 4597 22AWG STRAN TC WIR 19 8861 4-40 X 3/8 PAN PH MS SJ500 1
5408 _47P 100V 10%CAP T&R BEAD NPO 4 4599 22AWG SOLID SC WIR T&R 79 8741 4-40 X 1/2 PAN PH MS JS500 13
5410 100P 100V 10%CAP T&R BEAD NPO 4 5299 24AWG SOLID SC WIR RAD 43 8871 4-40 X 5/8 PAN PH MS SJ500 2
5412 220P 100V 10%CAP T&R BEAD NPO 2 4745 5.0W 0R1 5% BLK RES 12 8799 #6 X 1/4 PAN PH TYPE B JS500 2
5201 470P 100V 5%CAP T&R RAD CER.2"NPO 2 4749 5.0W 0R15 5% BLK RES 4 8801 6-32 X 3/8 PAN PH TAPTITE SJ500 1
5416 470P 50V 10%CAP T&R BEAD NPO 6 4974 1.0W 0R47 5%FLAME PROOF T&R RES 4 8829 6-32 X 3/8 FLAT PH TAPTITE BO#4 HEA 15
5816 680P 100V 5%CAP T&R RAD CER.2"NPO 2 4677 1/2W 1R 5% T&R RES 4 8747 6-32 X 1/2 HEX ND MS ZINC 16
5422 __1N 50V 10%CAP T&R BEAD NPO 2 4877 1/4W 1R 5% T&R RES 2 8761 6-32 X 1/2 PAN PHIL MS ZINC CLEAR 64
5273 __1N5 200V 5%CAP T&R RAD CER.2"NPO 2 4973 1.0W 1R 5%FLAME PROOF T&R RES 4 8806 6-32 X 1/2 PAN PH TAPTITE SJ500 2
5427 __2N2 500V 10%CAP T&R RAD CER.2" YB 4 4688 1/2W 2R2 5% T&R RES 7 8802 8-32 X 3/8 PAN QUAD TPTTE SJ500 #6H 7
6451 __4N7 250V 20%CAP AC Y ONLY RAD10MM 1 4911 1/4W 2R2 5% T&R RES 8 8749 10-32 X 1/2 QDX PH TAPTITE JS500 6
5272 __6N8 100V 5%CAP T&R RADIAL.2"FILM 2 4748 2.0W 3R9 5% BLK RES 2 8762 10-32 X1/2 TRUSS QUAD TAPTITE JS500 4
5204 _10N 100V 10%CAP T&R RADIAL.2"FILM 2 4733 5.0W 5R6 5% BLK RES 2 8833 10-32 X 7/8 HEX CAP GRD 5 SJ500 4
5834 _10N 250V 20%CAP RAD POLYFILM BULK 2 4610 1/4W 10R 2%FLAME PROOF T&R RES 8 8783 10-32 X 1 PAN QUAD TT JS500 BLACK 10
5210 _22N 100V 10%CAP T&R RADIAL.2"FILM 11 4875 1/4W 10R 5% T&R RES 2 8736 5/16-18X2-3/4 GRD 5 HEX BOLT JS500 1
6435 _22N 275V 20%CAP AC X2 RAD BLK15MM 2 4592 1/8W 15R 2%FLAME PROOF T&R RES 1 3433 0.080 SPACER OD.700 ID.330 PLASTIC 2
5224 _47N 100V 10%CAP T&R RADIAL.2"FILM 2 4591 1/8W 22R1 1%FLAME PROOF T&R RES 2 8663 11/64 NYLON SPACER (MICRO PLASTIC) 66
5226 _68N 100V 5%CAP T&R RADIAL.2"FILM 2 4607 1/8W 39R 2%FLAME PROOF T&R RES 8 8629 10-32 X 1/4 SPACER PHENOLIC 16
5228 100N 100V 5%CAP T&R RADIAL.2"FILM 4 4899 1/4W 39R 5% T&R RES 8 3741 .5 SPACER ID-.171 OD-.25 #912-500 2
5314 100N 50V 10%CAP T&R BEAD X7R 9 4817 1/4W 47R 5% T&R RES 6 3743 SNAP ON 0.5" SPACER RICHCO 3
5229 150N 63V 10%CAP T&R RADIAL.2"FILM 2 6134 1/4W 47R 5%MINI T&R RES 4 8679 6-32 X 1/4 X 1.75 NYLON SPACER(HEX) 1
5882 220N 250V 10%CAP RAD POLYFILM BULK 6 4811 1/4W 68R 5% T&R RES 2 8667 SHOULDER WASHER SWS-229 LENGTH 1/8 9
5234 470N 63V 10%CAP T&R RADIAL.2"FILM 2 4593 1/8W 150R 2%FLAME PROOF T&R RES 4 8818 3/4 OD X 5/16 ID X .08 THICK WASHER 1
5255 __1U 63V 20%CAP T&R RADIAL ELE.2" 2 4859 1/4W 150R 5% T&R RES 4 3511 #6 FLAT WASHER NYLON 2
5257 __2U2 63V 20%CAP T&R RADIAL ELE.2" 4 4645 1/8W 220R0 1%FLAME PROOF T&R RES 4 8485 #6 SPLIT WASHER ZINC 6
5259 __4U7 63V 20%CAP T&R RADIAL ELE.2" 5 4857 1/4W 220R 5% T&R RES 3 8491 #10 SPLIT LOCK WASHER BO 10
5281 _10U 16V 20%CAP NONPOLAR T&R .2" 6 4770 1/4W 249R 1% T&R RES 12 8817 #10 FLAT WASHER BLACK OXIDE 8
5629 _10U 160V 20%CAP RADIAL ELECT BULK 4 4867 1/4W 270R 5% T&R RES 7 8850 #10 INT TOOTH LOCKWASHER BO 4
5260 _22U 50V 20%CAP T&R RADIAL ELE.2" 12 4855 1/4W 330R 5% T&R RES 3 8873 1.250ODX5/16ID FENDER WASHER BARE 1
5627 _47U 10V 20%CAP NONPOLAR RAD BULK 2 4821 1/4W 470R 5% T&R RES 10 3436 DPDT PUSH SW PCMT H BREAK B4 MAKE 2
5267 100U 25V 20%CAP T&R RADIAL ELE.2" 2 4822 1/4W 820R 5% T&R RES 2 3422 THERMO/BRKR:N/CLOSED OPEN@60C 1
5619 330U 100V 20%CAP RADIAL ELECT BULK 4 4609 1/8W 1K 2%FLAME PROOF T&R RES 4 1288 AP-3400 T?RD 1
5630 330U 25V 20%CAP RADIAL ELECT BULK 6 4823 1/4W 1K 5% T&R RES 17
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