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Total solder points: 500Difficulty level:beginner1o 2o 3o 4o 5advanced
K8020
HIGH-END VALVE CONTROL AMPLIFIER
ILLUSTRATED ASSEMBLY MANUAL H8020IP-1
Val ve Contr ol Ampl ifier8020
Monitor
+6dB Aux CD Tuner AV
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VELLEMAN KIT NVLegen Heirweg 33
9890 GavereBelgium
http://www.velleman.be
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Assembly hints
1. Assembly (Skipping this can lead to troubles ! )Ok, so we have your attention. These hints will help you to make this projectsuccessful. Read them carefully.
1.1 Make sure you have the right tools:
A good quality soldering iron (25-40W) with asmall tip.
Wipe it often on a wet sponge or cloth, to keep it clean; then apply solder tothe tip, to give it a wet look. This is called thinning and will protectthe tip, and enables you to make good connections. When solderrolls off the tip, it needs cleaning.
Thin raisin-core solder. Do not use any flux or grease.
A diagonal cutter to trim excess wires. To avoid injury when cuttingexcess leads, hold the lead so they cannot fly towards the eyes.
Needle nose pliers, for bending leads, or to hold compo-nents in place.
Small blade and phillips screwdrivers. A basic range
is fine.
For some projects, a basic multi-meter is required, or mightbe handy
1.2 Assembly Hints :
Make sure the skill level matches your experience, to avoid disappointments.
Follow the instructions carefully. Read and understand the entire step beforeyou perform each operation.
Perform the assembly in the correct order as stated in this manual
Position all parts on the PCB (Printed Circuit Board) as shown on the draw-ings.
Values on the circuit diagram are subject to changes.
Values in this assembly guide are correct*
0.000
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Use the check-boxes to mark your progress.
Please read the included information on safety and customer service
* Typographical inaccuracies excluded. Always look for possible last minutemanual updates, indicated as NOTE on a separate leaflet.
1.3 Soldering Hints :
1-Mount the component against the PCB sur-face and carefully solder the leads
2-Make sure the solderjoints are cone-shaped and shiny
3-Trim excess leads as close as possible to thesolder joint
REMOVE THEM FROM THE TAPE ONE AT A
TIME !
Assembly hints
AXIAL COMPONENTS ARE TAPED INTHE CORRECT MOUNTING SEQUENCE !
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Color code table
I
P
E
SF
S
DK
N
D
GB
F
NL
C O D E
CODICE
COLO
RE
CODIGO
DE
CORES
CODIGO
DE
COLORE
S
VRI
KOODI
FRG
SCHEMA
FARVE-
KODE
FARGE-
KODE
FARB
KODE
COLOUR
CODE
CODIF
I-
CATIO
N
DES
COU-
KLEUR
KODE
C O D E
0
Nero
Preto
Negro
Musta
Svart
Sort
Sort
Sch
warzBlack
Noir
Zwart
0
1
Marro
neCastanhoMarrn
Ruskea
Brun
Brun
Brun
Bra
un
Brown
Brun
Bruin
1
2
Rosso
Encar-
Rojo
Punainen
Rd
Rd
Rd
Rot
Red
Rouge
Rood
2
3
Aran-
Laranja
Naran-
Oranssi
Orange
Orange
Orange
Ora
nge
Orange
Orange
Oranje3
4
Giallo
Amarelo
Amarillo
Keltainen
Gul
Gul
Gul
Gel
b
Yellow
Jaune
Geel
4
5
Verde
Verde
Verde
Vihre
Grn
Grn
Grnn
Gr
n
Green
Vert
Groen
5
6
Blu
Azul
Azul
Sininen
Bl
Bl
Bl
Blau
Blue
Bleu
Blauw
6
7
Viola
Violeta
Morado
Purppura
Lila
Violet
Violet
Violet
Purple
Violet
Paars
7
8
Grigio
Cinzento
Gris
Harmaa
Gr
Gr
Gr
Gra
u
Grey
Gris
Grijs
8
9
Bianco
Branco
Blanco
ValkoinenVit
Hvid
Hvidt
Weiss
White
Blanc
Wit
9
A
Argen
to
PrateadoPlata
Hopea
Silver
Slv
Slv
Silb
er
Silver
Argent
Zilver
A
B
Oro
Dourado
Oro
Kulta
Guld
Guld
Guldl
Gold
Gold
Or
Goud
B
5%
4K7=(4
-7
-2
-B)
1%
4K7=(
4-7-0-1-1)
COLOR=
2
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The unit consists out of two PCBs, one is the main PCB, P8020B and the otheris the left channel input section P8021L.First we will start with the small P8021L, then we assemble the P8021B.
FTip: The pictures on the packaging can beused as a guideline.However, due to possible changes it is not100% reliable.
CONSTRUCTION
q D1: 1N4148q D2: 1N4148q D3: 1N4148q D4: 1N4148q D5: 1N4148q D6: 1N4148
1. Diodes (check the polarity)
CATHODE
D...
q R1: 10K (1-0-3)q R2: 10K (1-0-3)q R3: 10K (1-0-3)q R4: 10K (1-0-3)q
R5: 10K 1-0-3)q R6: 10K (1-0-3)q R7: 1K (1-0-2)q R8: 1K (1-0-2)
2. Resistors (check the color code)
R...
Construction
P8021L
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q T1: BC557q T2: BC557q T3: BC557
q T4: BC557q T5: BC557q T6: BC557
5. transistors
q C1: 220p (221)q C2: 220p (221)q C3: 220p (221)q C4: 220p (221)q C5: 220p (221)q C6: 220p (221)
3. Capacitors
C...
Construction
q RY1: VR05051AS or eq.q RY2: VR05051AS or eqq RY3: VR05051AS or eqq RY4: VR05051AS or eqq RY5: VR05051AS or eqq RY6: VR05051AS or eq.
4- Reed relays (check the positionof the notch)
q SK1: MJ-523AG/B BLACKq SK2: MJ-523AG/B BLACKq SK3: MJ-523AG/B BLACK
q SK4: MJ-523AG/B BLACKq SK5: MJ-523AG/B BLACKq SK6: MJ-523AG/B BLACK
6. RCA connectors.Mount them straight andagainst the PCB
q SK7: HDR20/26
7. Pin connector. Mount it exactlyas indicated
RY...
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P8020B Assembly
Construction
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q J1... J26
1. Jump wires
q R01: 10K (1-0-3)q R02: 10K (1-0-3)q R03: 10K (1-0-3)q R04: 1K (1-0-2)q R05: 10K (1-0-3)q R06: 10K (1-0-3)q R07: 1K (1-0-2)q R08: 10K (1-0-3)q R09: 680R (6-8-1)q R10: 1M (1-0-5)q R11: 27K/0.6W (2-7-3-9)q R12: 10K (1-0-3)q R13: 3K6 1% (3-6-0-1)q R14: 100K (1-0-4)q R15: 5K6 (5-6-2)q R16: 680R (6-8-1)q R17: 3K6/1% (3-6-0-1)q R18: 33K/1% (3-3-0-2)q R19: 10K (1-0-3)q R20: 1M (1-0-5)q R21: 27K/0.6W (2-7-3-9)q R22: 10K (1-0-3)q R23: 3K6/1% (3-6-0-1)q R24: 100K (1-0-4)
q R25: 10K (1-0-3)q R26: 3K6/1% (3-6-0-1)q R27: 33K/1% (3-3-0-2)q R28: 680R (6-8-1)q R29: 5K6 (5-6-2)q R30: 1K (1-0-2)q R31: 1K (1-0-2)q R32: 27K/0.6W (2-7-3-9)q R33: 27K/0.6W (2-7-3-9)
q R34: 27K/0.6W (2-7-3-9)q R35: 1R (1-0)q R36: 10K (1-0-3)
3. Resistors (check the color code)
q D1: 1N4148q D2: 1N4148q D3: 1N4148q D4: 1N4148q D5: 1N4148q D6: 1N4148q D7: 1N4148q
D8: 1N4148q D9: 1N4148q D10: 1N4007q D11: 1N4007q D12: 1N4007q D13: 1N4007q D14: 1N4007q D15: 1N4007q D16: 1N4007q
D17: 1N4007q D18: 1N4007q D19: 1N4007q D20: 1N4007
2. Diodes (check the polarity)
CATHODE
D...
R...
Construction
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q R37: 4K7 (4-7-2)q R38: 10K (1-0-3)q R39: 4K7 (4-7-2)q R40: 10K (1-0-3)q R41: 1K (1-0-2)q
R42: 10K (1-0-3)q R43: 10K (1-0-3)q R44: 10K (1-0-3)q R45: 1K (1-0-2)q R46: 1K (1-0-2)q R47: 10K (1-0-3)q R48: 1K (1-0-2)
q Mount 9 pins ineach hole for thevalve supportsV1 and V2.
q Mount 3 pins inthe holes forVR1.
4. PCB pins
q IC1: 18P
5. IC sockets
q C01: 220p (221)q C02: 220p (221)q C03: 220p (221)q C04: 220p (221)q C05: 220p (221)q C06: 220p (221)q C07: 220p (221)q C08: 100n (104, 0.1, u1)
q C09: 100n (104, 0.1, u1)q C10: 100n (104, 0.1, u1)q C11: 100n (104, 0.1, u1)q C12: 100n (104, 0.1, u1)q C13: 100n (104, 0.1, u1)q C14: 100n (104, 0.1, u1)q C15: 100n (104, 0.1, u1)
6. Capacitors
C...
Construction
1
1
1
V1
V2
VR1
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q RY9: VR5C122C
9. Power relay
q T01: BC557q T02: BC557
q T03: BC557q T04: BC557q T05: BC557q T06: BC557q T07: BC557q T08: BC557q T09: BC557
q T10: BC547
8. transistors
RY...
q SK1: MJ-523AG/R REDq
SK2: MJ-523AG/R REDq SK3: MJ-523AG/R REDq SK4: MJ-523AG/R REDq SK5: MJ-523AG/R REDq SK6: MJ-523AG/R RED
11. RCA connectors.Mount them straight andagainst the PCB
q SK7: 20P (type 96120205)
7. Female header
q RY1: VR05051AS or eq.q RY2: VR05051AS or eqq RY3: VR05051AS or eqq RY4: VR05051AS or eqq RY5: VR05051AS or eqq RY6: VR05051AS or eq.q RY7: VR05051AS or eq.q RY8: VR05051AS or eq.
10. Reed relays (check the positionof the notch)
RY...
J...SK..
Construction
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q SW1: TS-04PVq SW2: TS-04PVq SW3: TS-04PVq SW4: TS-04PVq SW5: TS-04PV
Remark: The metal part of these but-tons are used as jump wire.Be sure not to test or use the unitwithout soldering these push buttons.
13. Push button
Mount them straight againstthe PCB surface !
Construction
q C16: 2,2uF( 2u2, 225 )q C17: 2,2uF( 2u2, 225 )q C18: 68nF/630V (0.068, 683)q C19: 68nF/630V (0.068, 683)q C20: 22nF/630V (0.022, 223)q C21: 4,7uF/160-250V( 4u7)q C22: 4,7uF/160-250V( 4u7)
14. Capacitors
C...
q V1: B9Aq V2: B9AThe valve socket is mounted on top of the allready mounted PCB pins.
First position the socket over the pins and solder one lead.
Check the hight of opprox. 23mm (0.9)
12. Valve socket mounting
5 9
8
7
4
3
2
V... 6 1
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q C23: 100q C24: 470q C25: 1000q C26: 1000q C27: 1000q C28: 47/350Vq C29: 47/350Vq C30: 47/350Vq C31: 47/350V
q C32: 47/350Vq C33: 47/350Vq C34: 47/350V
16. Electrolytic capacitors.Check the polarity !
q VR2: UA7805
VR1 will be mounted later
15. Voltage regulator.The back side corresponds tothe thick line.
C...
VR...
q TR1: TR8020, 2x18V, 12V, 220V/
16VA
First fix the transformer using four6mm M3 screws and nuts (nuts atsolder side), then solder his connec-tions.
Tip: It is advisable to secure thenuts using a drop of glue.
17. Transformer.
TRAFO...
Construction
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q RV1: STRK27103 (2x50K ALPS)
CAUTION:This is a high qualitypotentiometer, handle it with care.
Follow the mounting instructionsexactly and in order!
1.Mount the support bracket onto thepotentiometer. Tighten the nutcarefully.
2.Mount the potentiometer onto thePCB, using two 6mm (0.23)screws and M3 nut.
Only slightly tighten the nuts !Do not solder the potentiometerconnections yet !
18. Volume potentiometer.
Use a piece of isolated brown wire toselect the mains (outlet) voltage, as
indicated on the PC board.
q For 115Vac (100 to 120Vac)A jumper between A-B, and a jumperbetween C-D.
qFor 230Vac (220 to 240Vac)A jumper between B-C.
Using a black marker, erase thenot used voltage at the back of theunit.
19. Mains voltage selection
q Connect a 10cm blue wire to the
point Nof SK8.
q Connect a 10cm brown wire to the
point Lof SK8.
q Connect a 10cm yellow/green
wire to the earthpoint of SK8.
Later these connection will besoldered to the mains connector.
20. Mains voltage connectionpreparation
RV...
Construction
A B C D
B C
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First:Bend the leads exactly likethe drawing.
Next:Solder onelead, and checkthe position, if necessary correctby heating the soldering.
Last: Solder thesecond connection.
q LD7 L-424YDT
q LD1 L-424YDTq LD2 L-424YDTq LD3 L-424YDT
q LD4 L-424YDTq LD5 L-424YDTq LD6 L-424YDT
q LD8 L-424YDT
21. Mounting the LEDs. Check the polarity ! Short lead = Cathode or - !
Construction
7mm
C
12mm
IMPORTANTMount these LEDs exactly like in the
drawing, otherwise some LEDs will notfit correctly in the front panel.Please also use the front panel as a po-sitioning reference.
3mm
3mmC
CATHODE
LD...
FIG. 1
FIG. 2
FIG. 3
CAUTION: Afterbending theleads the long
appearing leadwill be the cath-ode!
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q Mount four 2cm (0.8)M3 spacers at the indi-cated positions usingfour 6mm (0.23) M3screws.
22. Mounting the sub PCB support
Construction
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q Cut the thread in the holes for the en-closure feet in one of the aluminum
profiles, using the supplied specialM4 screw as a tap.
q Cut the thread in the front andback of the aluminum profiles,using the supplied special M4screw (4 holes per piece)
q Mount the feet on the aluminum pro-file, using four M4 hexagonal Allenscrews. Use the supplied Allenwrench. It is advisable to stick the pro-tection adhesive onto the feet.
q Mount the valve pro-tection covers on oneof the aluminum pro-files. Use four M4 hex-agonal Allen screws.
23. Enclosure preparation
Enclosure preparation
FIG. 2
FIG. 3
FIG. 4
FIG. 1
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q Position the main PCB in thealuminum profile that is pre-pared with the feet.
q Mark the center position of the three fixation holes on the aluminum.
Align pcb with profile !
Enclosure preparation
FIG. 5
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q Remove the pcb and use aknife or a screwdriver toscratch the paint from the alu-minum fixation, from the hole
closest to the back end. Thisfixation will be used later toconnect the ground andearth.
q Mount the 3, 5mm(0.14) spacers like inthe drawing. Usingthree hexagonalscrews and awasher. Do not tightenthe spacers yet.
q Position the PCB in the enclosure and check if the position of the spacers iscorrect, if so, remove the PCB and tighten the spacers.
q Using an ohmmeter, measure between the edge of the aluminum profile andthe back spacer, if there is a good electric contact (0 ohm). If not, repeat theabove step to remove the paint under the spacer.
Enclosure preparation
FIG. 6
M3 hex. nut5mm M3 spacer
Washer
FIG. 7
0.000FIG. 8
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Final assembly
q Mount the PCB into the enclosure like before.
q Fix the pcb using a5mm spacers next toC9.
q Mount the knob onto the potentiome-ter. (check the notch position)
FUse the supplied Allen wrench
Tip: Check if thepcb does not haveto much play at thepotentiometer posi-tion.If there is too muchplay, put a piece oftape round the edge of the pcb to removethe slack.
Play?
24. Potentiometer assembly and final PCB mount
FIG. 1
FIG. 2
MAXMIN
FIG. 3
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q Now carefully mount the front panel, us-ing two M4 Allen screws. Check the posi-tion of the LEDs.
q Check if the potentiometer turns smoothly
without touching the front panel, other-wise correct his position or the position ofthe front panel.
FUse the supplied Allen wrenchq Remove the front panel and fix the nuts of the potentiometer bracket.q Remove the PCB from the enclosure and solder the potentiometer connec-
tions.
IMPORTANT:q Slide an M3 hexagonal screw into the profile
side. Position the screw about in the center ofthe profile.
q Again mount the pcb into the enclosure.
q Fix the pcb using a 2cm (0.8)spacer at the position next toSK07 and use 5mm spacers tofix the other two positions.Measure, using an ohm meter(or continuity beeper) if the2cm spacer is electrically con-nected to the ground wire
(yellow green wire). If not, re-check if the paint of the alumi-num is correctly removed.
q Mount the left channel PCB ontothe spacers, check that the con-nector is correctly inserted. Fix thePCB using five 6mm M3 screws.
Final assembly
FIG. 4
SPACER
FIG. 6
FIG. 5
FIG. 7
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Mounting the voltage regulator:q VR1: 7812 (isolated plastic type)
First bend his leads like in the drawing
Then mount him onto the previously in-serted hexagonal screw, at the appropri-ate position according to the PCB. Use a5mm spacer screw.
Last solder his connections.
q Mount (insert) themains connector ontothe rear panel. Insert a250mA fuse into theconnector (there is alsoroom for a spare fuse).
q Mount the rear panelonto the enclosure, us-ing two M4 Allen
screws.
25. Final assembly and connection
Final assembly
FIG. 1
FIG. 2
FIG. 3
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q Connect the mains wires to the
mains connector, Blue= Neutral,Brown= Live, and green/yellow=Earth. Use a piece of 1.5cm (0.6)shrink tube to isolate each connec-
tion.
q Mount the front panel onto thefront, using two M4 Allenscrews.
FCheck the position of theLEDs and check if all buttons
are working correctly.
It could be that paint rest overin the holes, is preventing thebuttons from smooth opera-tion.
Test
FIG. 4
FIG. 5
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Insert the IC into his socket. Watch the position of the notch!
qIC1 VK8020 / PIC16C54RC
Insert the valves into their socket (watch the position)q V1: ECC82, 12AU7, CV491, 6189, 8136q V2: ECC82, 12AU7, CV491, 6189, 8136
Connect the power cord to the mains connector.Connect the power cord to the mains output
CAUTION: Some points on the PCB are connected to the danger-ous mains voltage or high DC voltage.
Push the power button (or one of the input selection buttons)Check if the power supply LED LD08 is lit. This means that the high voltage iscorrect.Normally the valves filaments (or heaters) must also work.
Disconnect the mains plug.
Check the user manual to test all functions and operation of the unit, then thealuminum cover can be mounted.
Please note that the user manual is also used for the ready assembled version.Some remarks may not be related to the kit version.
26. IC and Valve mounting
!
Diagram
27. Test
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Diagram
POWER SUPPLY SECTION
CONTROLLER SECTION Velleman Kit
D101N4007
D111N4007
D16
1N4007 D19 1N4007
D18
1N4007
D17
1N4007
C10
100n
C11
100nA
D
C
B
230V
N
B+C
115V
L
A+BC+D
IO
GND
VR2uA7805+5V
C15
100n
C14
100n
C13
100n
C12
100n
C23
100
C27
1000
C26
1000
C24
470
+12.5V
R351R
SK10
SK09
SK08
R09680R
C08
100n
Mains selection
MAINS
TR1
D131N4007 D12
1N4007
D15
1N4007
D14
1N4007
D09
1N4148
RY9
PWR
+12V
+12V
C25
1000
C29
47/350V
C28
47/350V
C30
47/350V
+300V
R34
27K/0.6W
R30
1K
R31
1K
C2022n/630V
IO GND
VR1 uA7812P
R33
27K/0.6W
R32
27K/0.6W
LD8
L-424YDT
18V
18V
12V
220V
0
21V@230Vac in
265V@230Vac in
RA0 17
RA1 18
RA2 1
RA32
RB06
RB17
RB28
RB3 9
RB4 10
RB511
RB6 12
RB7 13
VSS
5
MCLR/VPP4
OSC1/CLKIN16
T0CKI3
OSC2/CLKOUT 15
VDD14
IC1
PIC16C54RC
R39
4K7C07
220p
Input1
Input2
Input3
Input4
Monitor
+6dB
Mute
R4710K
R4410K
R4310K
R4210K
R4010K
+5V SW4
SW3
SW2
SW1
SW5
R451K
R481K
+5V
R461K
R41
1K
LD1L-424YDT LD2L
-424YDT
LD5L-424Y
DT LD6
L-424YDT
LD7L-424Y
DTLD4L-424YDT
LD3L-424Y
DT
C09
100n
REC
TUNER
CD
PU/LINE
STBY / MUTE
T09
BC557
R38
10K
T10
BC547
R37
4K7
R36
10K
+5V
PWR
D201N4007
+12V
+5V
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Diagram
RY1
T1
BC557
SK1
R1
10K
C1
220p
D1
1N4148
+5V
RY2
T2
BC557
SK2
R2
10K
C2
220p
D2
1N4148
+5V
RY3
T3
BC557
SK3
R3
10K
C3
220p
D3
1N4148
+5V
RY4
T4
BC557
SK4
R4
10K
C4
220p
D4
1N4148
+5V
RY5
T5
BC557
SK5
R5
10K
C5
220pD5
1N4148
+5V
RY6
T6
BC557
SK6
R6
10K
C6
220p
D6
1N4148
+5V
R8
330R
R7
1K
+5V 1
23456789101112131415161718
1920
SK7
CD
PU/LINE
TUNER
REC
MONITOR
LINE OUT L
LEFT INPUT / OUTPUT SECTION Velleman Kit
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RIGHT INPUT / OUTPUT SECTIONAND AMPLIFIER SECTION
Velleman Kit
RY1
T01
BC557
SK01
R0110K
C01
220p
D01
1N4148
+5V
Input1
RY2
T02
BC557
SK02
R0210K
C02
220p
D02
1N4148
+5V
Input2
RY3
T03
BC557
SK03
R0310K
C03
220p
D03
1N4148
+5V
Input3
RY4
T04
BC557
SK04
R0510K
C04
220p
D04
1N4148
+5V
Input4
RY5
T05
BC557
SK05
R0610K
C05
220pD05
1N4148
+5V
Monitor
RY6
T06
BC557
SK06
R08
10K
C06
220p
D06
1N4148
+5V
Mute
R07
1K
R04
1KC16
2.2uF
+12.5V
R16680R
R112
7K/0.6W
R101M
+5V
RY8D08
1N4148
+5V
+6dB
R13
3K6 1%
RV1B
50K
RV1A
50K
C17
2.2uF
123456789
1011121314151617
181920
SK07
Input1Input2
Input3Input4
MuteMonitor
Line out L
Line out L
CD
PU/LINE
TUNER
REC
MONITOR
LINE OUT R
1
2
3
5 9 4
8
6
7V1
ECC82
C32
47/350VC31
47/350V
R17
3K6 1%
R14
100K
R1833K1%
R1210K
T08
BC557
R1910K
C18 68n/630V
C21
4u7/160V
+300V
R155K6
+12.5V
R28680R
R2127K
/0.6W
R201M
+5V
RY7D07
1N4148
+6dB
R233K6 1%
1
2
3
5 9 4
8
6
7V2
ECC82
C34
47/350VC33
47/350V
R26
3K6 1%
R24
100K
R2733K1%
R2210K
T07
BC557
R25
10K
C19 68n/630V
C22
4u7/160V
R295K6
+300V
Line out R
Line out R
170v
7V -4V 115V
130V - 100V
220V
Diagram
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VELLEMAN KIT NVLegen Heirweg 33
9890 GavereBelgium Europe
Info ?: http://www.velleman.beQuestions ?: [email protected]
Modifications and typographical errors reserved Velleman Kit nv
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