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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 ?: support@velleman.be

Modifications and typographical errors reserved Velleman Kit nv