Total solder points: 600 Difficulty level: beginner 1 2 3 4 5; advanced MONO PURE CLASS POWER AMPLIFIER HIGH-Q A VALVE K8010 ⇒ ⇒ ⇒ ⇒ ⇒ ⇒ ⇒ ⇒ ⇒ ⇒ Pure CLASS A valve sound with high quality KT88 valves High quality chrome plated enclosure Chrome plated valve socket covers Easy bias adjustment with LED indication Removable bottom for easy access and service High quality capacitors and components Gold plated input and speaker terminals Standby function Soft start circuit for power transformer Sensitivity adjustment for exact matching of two mono amps Specifications • • • • • • • • • Full class A 65Wrms in 4 or 8Ω Bandwidth: 4Hz to 90KHz (-3dB/1W) Harmonic distortion: 0.1% @ 1W/1KHz Signal to noise ratio: >110dB (A weighted) Input sensitivity: 1Vrms (adjustable) Power supply: 100, 120, 230 or 245VAC Power consumption: 230VA max. Dimensions: 355W x 360D x 157H Weight: 14Kg / 31lb modifications reserved MANUAL H8010P-ED1 5% 1% 4K7= ( 4 - 7 - 2 - B ) I P C CODICE CODIGO DE O COLORE CORES D E 0 1 2 3 4 5 6 7 8 9 A B Nero Marrone Rosso Aranciato Giallo Verde Blu Viola Grigio Bianco Argento Oro Preto Castanho Encarnado Laranja Amarelo Verde Azul Violeta Cinzento Branco Prateado Dourado COLOR= 2… 5 4K7= ( 4 - 7 - 0 - 1 - 1 ) E CODIGO DE COLORES Negro Marrón Rojo Naranjado Amarillo Verde Azul Morado Gris Blanco Plata Oro SF VÄRI KOODI Musta Ruskea Punainen Oranssi Keltainen Vihreä Sininen Purppura Harmaa Valkoinen Hopea Kulta S DK N FÄRG FARVE FARGE SCHEMA KODE KODE Svart Brun Röd Orange Gul Grön Blå Lila Grå Vit Silver Guld Sort Brun Rød Orange Gul Grøn Blå Violet Grå Hvid Sølv Guld Sort Brun Rød Orange Gul Grønn Blå Violet Grå Hvidt Sølv Guldl D FARB KODE Schwarz Braun Rot Orange Gelb Grün Blau Violet Grau Weiss Silber Gold GB F COLOUR CODIFI- CODE CATION DES COULEURS Black Brown Red Orange Yellow Green Blue Purple Grey White Silver Gold Noir Brun Rouge Orange Jaune Vert Blue Violet Gris Blanc Argent Or NL KLEUR KODE C O D E Zwart Bruin Rood Oranje Geel Groen Blauw Paars Grijs Wit Zilver Goud 0 1 2 3 4 5 6 7 8 9 A B __________________________________________________________________________________________________________________________________________________________ TECHNICAL DAT A* • • • • • • • • • • • • • • • • • Output power: 65 Wrms class A / 85Wrms maximum Output impedance 4 or 8 Ohm Ultra linear output transformer Switch-on delay, to protect the output tubes: approx. 1 minute Standby circuit Built-in bias current indicator Switch-on delay for the supply transformer : 0.5s Power bandwidth: 8Hz - 45kHz (-3dB, ref. 50W) Frequency range: 4Hz - 90kHz (-3dB, ref. 1W) Harmonic distortion: 0.1% (1 kHz/1W) 0.7% (1 kHz/65W) Signal/noise ratio: > 110dB (A weighted wrt 85W) Input impedance: 100Kohm Input sensitivity min 1Vrms, adjustable. Damping factor (100Hz): > 12 Power supply: 100, 120, 230, 245VAC Power consumption: 230Wmax. / 66W standby Dimensions: 355W x 360D x 157H *Modifications and typographical errors reserved 3 _________________________________________________________________________________________________________________________________________________ ______ 1. Assembly (Skipping this can lead to troubles ! ) Ok, so we have your attention. These hints will help you to make this project successful. Read them carefully. 1.1 Make sure you hav e the right tools: • A good quality soldering iron (25-40W) with a small tip. • Wipe it often on a wet sponge or cloth, to keep it clean; then apply solder to the tip, to give it a wet look. This is called ‘thinning’ and will protect the tip, and enables you to make good connections. When solder rolls 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 cutting excess leads, hold the lead so they cannot fly towards the eyes. • Needle nose pliers, for bending leads, or to hold components in place. • Small blade and phillips screwdrivers. A basic range is fine. For this projects, a basic multi-meter is required 0.0 0 0 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 before you 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 drawings. ; Values on the circuit diagram are subject to changes. ; Values in this assembly guide are correct* ; 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 minute manual updates, indicated as ‘NOTE’ on a separate leaflet. 1.3 Soldering Hints : Mount the component against Make sure the solder joints are the PCB surface and carefully cone-shaped and shiny solder the leads 4 Trim excess leads as close as possible to the solder joint __________________________________________________________________________________________________________________________________________________________ ASSEMBLY OF THE MAIN PCB P8010: Foreword: For best results and easy handling of the large PCB (Printed Circuit Board), we will start by putting the four large valve sockets in place. This will allow us to rest the board on the bench, without having the component leads touching the bench surface. When the component leads are put in the appropriate holes on the PCB, we recommend to gently bend the leads outwards, so they stay on the board when it is flipped over to apply solder. You gain a reasonable amount of time if you put approx. 10 components in place every time, before you flip the board, and make the solder joints. 5 _________________________________________________________________________________________________________________________________________________ ______ 1. VALVE SOCKET MOUNTING Check the position of the notch in the centre of the valve socket, it must correspond to the position of the notch in the circle printed on the PCB. Connect the leads to the corresponding isles on the PCB using a small piece of supplied jumper wire. IMPORTANT: Make the connection exactly as shown in the illustration, otherwise the small piece of wire could touch the bottom of the cabinet, see further. Also mount a 15 mm spacer on the following holes in the PCB (at the solder side); use a 6 mm M3 bolt: 3 V... 1 4 5 8 2 7 A spacer next to TRAFO1 A spacer next to SK15 A spacer next to SK6 A spacer next to R62 A spacer next to V6 6mm M3 BOLT 20mm M3 BOLT VALVE SOCKET 15mm M3 SPACER 12mm SPACER PCB 15mm M3 SPACER 5 6 8 7 5 8 4 3 4 1 2 1 3 6 V1 V2 V3 V4 Connect the valve socket terminals 1, 3, 4, 5, and 8 to the corresponding points at the solder side of the PCB. Use a piece of supplied jumperwire. Mount the wire in such way that it cannot touch the bottom of the cabinet. (see above illustration). __________________________________________________________________________________________________________________________________________________________ 2. JUMPERS Note that for J1 to J4, two jumper wires have to be mounted in the same hole, for extra current handling. TIP In order to get nice straight wiring, without too much folding and measuring, follow these hints: • Put the jumper wire in place. • Solder one end of the lead. • Then carefully pull on the free end of the lead until it is straight, and apply solder. N ld th th d 3. JUMPERS FOR AC POWER SELECTION For 100V input (mains), mount: JA at the voltage selection 1 D C B A JA at the voltage selection 2 D J1 (mount 2 wires in the same hole) J2 (mount 2 wires in the same hole) J3 (mount 2 wires in the same hole) J4 (mount 2 wires in the same hole) J5 J6 J7 J8 J9 J10 J11 J12 J13 J14 J15 J16 J17 J18 J19 J20 J21 J22 indicated with ‘F1’ (mount 2 wires in the same hole) C B A For 115V - 120V input, mount: JB at the voltage selection 1 D C B A JB at the voltage selection 2 D C B A 7 _________________________________________________________________________________________________________________________________________________ ______ 4. DIODES (Check the polarity!) For 220V - 230V input, mount: JC at the voltage selection 1 D C D... CATHODE B A JC at the voltage selection 2 D C B A For 240V -245V mains input, mount: JD at the voltage selection 1 D C B A JD at the voltage selection 2 D C B A REMARK: Strike out the NOT used mains voltage indication at the back of the enclosure !! Use a permanent black marker 8 D1: 1N4148 D2 :1N4148 D3: 1N4007 D4: 1N4148 D5: 1N4007 D6: 1N4148 D7: 1N4148 D8: 1N4148 D9: 1N4007 D10: 1N4007 D11: 1N4007 D12: 1N4007 D13: 1N4007 D14: 1N4007 D15: 1N4007 D16: 1N4007 D17: 1N4007 D18: 1N4007 D19: 1N4007 D20: 1N4007 D21: 1N4007 D22: 1N4007 D23: 1N4007 D24: 1N4148 D25: 1N4148 D26: 1N4148 D27: 1N5408 D28: 1N5408 D29: 1N5408 D30: 1N5408 not on not on not on not on tape ! tape ! tape ! tape ! __________________________________________________________________________________________________________________________________________________________ 5. ZENER DIODES (Check the polarity!) ZD... CATHODE ZD1: 3V9 ZD2: 3V9 6. ¼W & ½W RESISTORS R... R1: 470 (4 - 7 - 1 - B) R2: 220K (2 - 2 - 4 - B) R3: 2K2 (2 - 2 - 2 - B) R4: 2K2 (2 - 2 - 2 - B) R5: 220K (2 - 2 - 4 - B) R6: 100K (1 - 0 - 4 - B) R7: 1K (1 - 0 - 2 - B) R8: 1K (1 - 0 - 2 - B) R9: 22K (2 - 2 - 3 - B) R10: 3.3 (3 - 3 - B - B - 9) R11: 3K9 (3 - 9 - 2 - B) R12: 1K5 (1 - 5 - 2 - B) R13: 1M (1 - 0 - 5 - B) R14: 1M (1 - 0 - 5 - B) R15: 1K (1 - 0 - 2 - B) R16: 47K (4 - 7 - 3 - B) R17: 470K (4 - 7 - 4 - B) R18: 680 (6 - 8 - 1 - B) R19: 3K9 (3 - 9 - 2 - B) R20: 10K (1 - 0 - 3 - B) R21: 10K (1 - 0 - 3 - B) R22: 1K5 (1 - 5 - 2 - B) R23: 1K2 (1 - 2 - 2 - B) R24: 560 (5 - 6 - 1 - B) R25: 100K (1 - 0 - 4 - B) R26: 220K (2 - 2 - 4 - B) R27: 100K (1 - 0 - 4 - B) R28: 220K (2 - 2 - 4 - B) R29: 10K (1 - 0 - 3 - B) R30: 2K7 (2 - 7 - 2 - B) R31: 1M5 (1 - 5 - 5 - B) R32: 1K5 (1 - 5 - 2 - B) R33: 3.3 (3 - 3 - B - B) R34: 8K2 (8 - 2 - 2 - B) R35: 220K (2 - 2 - 4 - B) R36: 10K (1 - 0 - 3 - B) R37: 100K (1 - 0 - 4 - B) R38: 220K (2 - 2 - 4 - B) R39: 100K (1 - 0 - 4 - B) R40: 220 (2 - 2 - 1 - B - 9) R41: 100K (1 - 0 - 4 - B - 9) R42: 47K (4 - 7 - 3 - B - 9) R43: 220 (2 - 2 - 1 - B - 9) R44: 220 (2 - 2 - 1 - B - 9) R45: 220 (2 - 2 - 1 - B - 9) R46: 2K2 (2 - 2 - 2 - B - 9) R47: 27K (2 - 7 - 3 - B - 9) R48: 220 (2 - 2 - 1 - B - 9) R49: 220 (2 - 2 - 1 - B - 9) R50: 100K (1 - 0 - 4 - B - 9) R51: 330K (3 - 3 - 4 - B - 9) R52: 330K (3 - 3 - 4 - B - 9) R53: 330K (3 - 3 - 4 - B - 9) R54: 330K (3 - 3 - 4 - B - 9) 9 _________________________________________________________________________________________________________________________________________________ ______ 7. 1W RESISTORS 8. LEDs (Check the polarity!) R... COLOR = 2...5 LD... 2mm CATHODE R55: 270 (2 - 7 - 1 - B) R56: 10K (1 - 0 - 3 - B) R57: 10K (1 - 0 - 3 - B) R58: 12K (1 - 2 - 3 - B) R59: 39K (3 - 9 - 3 - B) R60: 39K (3 - 9 - 3 - B) R61: 39K (3 - 9 - 3 - B) R62: 100K (1 - 0 - 4 - B) R63: 47K (4 - 7 - 3 - B) R64: 47K (4 - 7 - 3 - B) R65: 47 (4 - 7 - 0 - B) R66: 47 (4 - 7 - 0 - B) R67: 180 (1 - 8 - 1 - B) R68: 180 (1 - 8 - 1 - B) R69: 180 (1 - 8 - 1 - B) R70: 47 (4 - 7 - 0 - B) R71: 47 (4 - 7 - 0 - B) R72: 180 (1 - 8 - 1 - B) LD1: 5mm RED (2) BLINKING LD2: WILL BE MOUNTED LATER, SEE SECTION 27 LD3: 3mm YEL (4) LD4: 3mm YEL (4) LD5: 3mm YEL (4) LD6: 3mm YEL (4) LD7: 3mm GREEN (5) LD8: 3mm GREEN (5) LD9: 3mm RED (2) LD10: 3mm RED (2) LD11: 3mm RED (2) LD12: 3mm RED (2) LD13: 3mm RED (2) (next to R61) 9. IC SOCKETS (Check the position of the notch!) 1 IC... 10 IC1: 18P __________________________________________________________________________________________________________________________________________________________ 10. REED RELAYS (Check the position of the notch!) 12. RESISTOR TRIMMERS Vertical type 1 PIN 1 RV... RY... RY1: VR05R121 11. DIP SWITCHES RV1: 100K RV2: 100K RV3: 100K RV4: 100K Horizontal type SW... 1 RV... Check that switch 1 corresponds to pin 1. SW2: DS-4P RV5: 500K (470K) 11 _________________________________________________________________________________________________________________________________________________ ______ 13. TRANSISTORS 15. PCB BLADE TERMINALS T... Mount them as straight AS possible against the PCB. A good solder joint is very important ! T... SK... T... T... T1: BC516 T2: BC547C T3: BC547C T4: BC547C 14. 5W RESISTORS R... SK1: 4 Ohm SK2: GND SK3: 8 Ohm SK4: BLUE SK5: RED SK6: YELLOW SK7: GRAY SK8: GRAY SK9: GREEN SK10: GREEN SK21: EARTH SK22: EARTH 16. CINCH / RCA CONNECTOR 2mm Mount it as straight and square as possible against the PCB. REMARK: You will have one 15 Ohm 5W resistors left over for later use. R73: 15 R74: 15 R75: 15 12 SK11: CINFP/90 __________________________________________________________________________________________________________________________________________________________ 17. PCB TERMINAL BLOCK 19. SWITCH some blocks slide into each other ! SW... IMPORTANT: Don't leave a gap between the SWITCH and the PCB! Mount these terminals with the wire inputs facing the PCB edge: SK12: 2 POLE (large) SK13: 3 POLE SK14: 3 POLE SK15: 3 POLE SK16: 3 POLE SK17: 3 POLE SIDE VIEW Mount it as square as possible against the PCB, Also solder the metal support. SW1: 3P ON-ON-ON SK18 to SK20 are not mounted 20. CAPACITORS 18. VALVE SOCKET C... 1 6 V... 2 7 3 8 5 Mount them straight against the PCB V5: B9A V6: B9A 9 4 Check the voltage rating! C1: 47nF (473, 0.047, 47000) C2: 100pF (101) C3: 330pF/400V (331) C4: 330pF/400V (331) C5: 68n/630V (683, 0.068) C6: 68n/630V (683, 0.068) C7: 68n/630V (683, 0.068) C8: 68n/630V (683, 0.068) C9: 68n/630V (683, 0.068) C10: 68n/630V (683, 0.068) C11: 680n/160V (684, 0.68) C12: 680n/160V (684, 0.68) C13: 680n/160V (684, 0.68) 13 _________________________________________________________________________________________________________________________________________________ ______ 21. POWER RELAYS The various relays have footprints that correspond to the footprints on the PCB: 22. ELECTROLYTIC CAPACITOR (Check the polarity!) RY2: VR10V121C RY3: VR10V121C C... RY... RY4: VR5V122C RY... 14 C14: 4µ7 C15: 100µF C16: 470µF C17: 470µF C18: 470µF C19: 470µF C20: 47µF/100V C21: 100µF/100V C22: 1000µF C23: 4700µF C24: 47µF/350V C25: 47µF/350V C26: 100µF C27: 1µF __________________________________________________________________________________________________________________________________________________________ 23. TRANSFORMER 25. INSERT THE IC (Check the position of the notch!) 1 PIN 1 IC... TRAFO... IC1: LM3914 TRAFO1: 12VAC 24. ELECTROLYTIC CAPACITOR (Check the polarity!) Generally these capacitors are of the snap-in type and cannot be mounted incorrectly. C... C28: 100u/400V C29: 220u/450V C30: 220u/450V C31: 220u/450V 15 _________________________________________________________________________________________________________________________________________________ ______ 26. 6.3V VALVE WIRING Wiring for the 4 valve sockets V1 to V4. Use the supplied brown wire. Twist them as shown in the illustration. The polarity is not important. For safety, it is advisable to check with an ohmmeter that the two 6.3V terminals are not shorted when the wiring is completed. 6.3VAC f6 f8 f7 f5 f4 f3 6.3VAC f2 f1 3 5 7 6 8 5 1 8 4 2 3 1 8 1 4 4 5 3 4 1 2 8 V4 3 7 6 5 V1 V3 5 6 V2 7 8 5 1 3 1 8 8 4 3 2 1 4 4 5 4 3 3 2 1 8 7 6 5 VIEWED FROM SOLDERSIDE 27. SPECIAL LED (Check the polarity!) LD2: 3mm bicolor: Carefully check the mounting of this LED: 3 1 2 1 3 5mm LD2 ONLY ! 2 LD... 5mm Check the complete assembly again for errors. Pay special attention to bad solder joints, shorts and wrongly inserted or misplaced components ! 16 __________________________________________________________________________________________________________________________________________________________ ASSEMBLY INTO THE CABINET: • Mount the caged nuts into the square holes as shown in the illustration. These nuts are later used to fasten the covers. CLICK INTO HOLE FIG 1 • Mount the chromed feet on the four cabinet corners, with an M4 bolt. To avoid scratches on other equipment, you can stick a piece of felt on every foot (not supplied). • Mount a shakeproof washer and a 15mm threaded spacer on the front and back studding as shown in the illustration. 15mm M3 SPACER M3 LOCK WASHER M3 BOLT FIG 2 • Position the PCB in the cabinet, and fasten at the bottom with the supplied black button head hexagon socket screws (Use the supplied Allen key). At the component side of the PCB, two M3 bolts fasten the PCB on the threaded spacers we mounted in the previous step. • The mains inlet located at the back of the enclosure will be flush mounted as shown in the illustration. Use two black button head hexagon socket screws , together with a shakeproof washer and an M3 nut. M3 BOLT MAINS INLET M3 LOCK W ASHER M3 NUT FIG 3 17 _________________________________________________________________________________________________________________________________________________ ______ • Make the connections as shown. Use the supplied blue wire for the neutral (N) terminal, and brown wire for the live (L) terminal. FIG 4 The earth terminal is hooked up with green/yellow striped wire. green/yellow striped wire must be soldered for best results. The female push-on connector on the SOLDER FIG 5 Connect the earth wire to SK21 on the PCB. Remove the fuse holder lid, and insert a miniature glass fuse. For mains voltages of 100-125VAC, use the supplied 8A slow-blow fuse, while for 220-240VAC operation the 4A slow-blow fuse needs to be fitted. The spare fuse can also be stored in the fuse holder lid. • Mounting of the speaker terminals: Mount them as shown in the diagram. Watch the position of the plastic insulator rings : one is flat, while the other has an elevated ring on the inside. There is no need to mount the solder lugs. SPEAKER TERMINAL INSULATOR RING NUT NUT INSULATOR RING FIG 6 HINT : For easy fastening of the speaker terminals, immobilise the terminal by inserting a screwdriver in the wire hole, while fastening the nuts. IMPORTANT : The speaker terminals must be electrically isolated from the metal enclosure. For safety, check for infinite resistance between every terminal and the metal enclosure. • Use the supplied 1,5mm² wire to make the connections. For best results, solder the female push-on connector (fig 5). Apply enough heat, in order to make a good solder joint. 18 __________________________________________________________________________________________________________________________________________________________ FIG 7 • Mounting of the toroid transformers : The output transformer marked ZD043 must be fitted according to the illustration, on the right hand side of the cabinet. Watch the location of the wires. RUBBER WASHER OUTPUT TRANSFORMER RUBBER WASHER M8 BOLT STEEL DISHED WASHER FIG 8 ! IMPORTANT : Do not trim the wires of the transformers, leave them at their original length. If there is more than one conductor in an insulating sleeve, you have to make sure they are soldered together and make a good electrical connection before they are connected to the terminal block. 19 _________________________________________________________________________________________________________________________________________________ ______ • Connect the double yellow wire with the connector marked ‘YELLOW’ SK6. Connect the red wire with the connector marked ‘RED’ SK5. Connect the blue wire with the connector marked ‘BLUE’ SK4. Use the supplied female push-on connectors (fig 5) and solder them onto the wires ! Connect the remaining wires to the terminal blocks SK16 and SK17. Pay attention to the colors. FIG 9 • The supply transformer must be fitted according to the illustration, on the left hand side of the cabinet. Watch the location of the wires. The sturdy grey and green wires, which supply the 6,3V filament voltage, must sit on top. RUB BER W ASHE R PO W ER TRA NSF O RME R RUBB ER W ASHER ST EEL DISHED W ASH ER M8 BO LT FIG 10 20 __________________________________________________________________________________________________________________________________________________________ • Connect the grey wires to the connectors marked SK7 and SK8 (GRAY). Connect the green wires to the connectors marked SK9 and SK10 (GREEN). Connect the remaining leads to the terminal blocks SK13, SK14 and SK15 FIG 11 FINAL INSPECTION : ! WARNING : THE PCB CARRIES VOLTAGES THAT EXCEED 400V ! THESE VOLTAGES CAN KILL ! MAKE SURE NO ONE CAN TOUCH ANY LIVE PARTS Use suitable isolated measuring equipment • Put the mains switch into its fully OFF position (all the way down). • Connect the unit to a wall outlet, by means of the supplied cord. In some countries, the supplied plug will not fit the local wall outlets. If this is the case, cut the supplied plug, and replace it with a suitable one (not included). Make sure to wire it correctly : blue : neutral (N), brown : live (L), yellow/green : earth. If the mains voltage is present, LD2 should light continuously red. • Turn the unit on by pushing the mains switch to its fully upward position. LD2 should now blink for a while, this indicates the standby mode. After approximately one minute, LD2 should light continuously green, indicating ‘ON’, and a relay should click. • Now check the following voltages with a multimeter: Measure about 6.3VAC between SK7-SK8 and SK9-SK10 Measure about 6.3VAC between pins 2 and 7 of the tube sockets V1 to V4 (illustration) FIG 12 21 _________________________________________________________________________________________________________________________________________________ ______ ! SWITCH OFF THE UNIT AND REMOVE THE MAINS PLUG. WAIT A COUPLE OF MINUTES UNTIL THE DANGEROUS HIGH VOLTAGE HAS DISSAPEARED (UNTIL HIGH VOLTAGE INDICATOR LD13 TURNS OFF) • Put the small valves in place: V6 type ECC82 or 12AU7, CV491, 6189, 8136 V5 type ECC81 or 12AT7, CV455, 6201, 8162 • Reconnect the mains plug, and switch the unit ON again (switch in full upward position) Wait until LD2 lights green continuously. • Now check all indicated voltages on the PCB with respect to ground. A suitable ground for these measurements is J4, at the centre of the PCB. The point indicated VB2 should carry approx. 3.5VDC. REMARK : All voltages may vary a bit, due to mains voltage fluctuations. At this stage, you cannot measure the 3.6VDC voltages yet. CALIBRATION Switch off the unit, disconnect the mains plug and wait until the high voltage has disappeared. Turn the trim potentiometers RV1 to RV4 fully counter clockwise with a small screwdriver. Put the four KT88 or equal tubes in their sockets. Watch the position of the notch. IMPORTANT : The remaining 15 Ohm / 5W resistor must be hooked up between the centre and the 8 ohm speaker terminal at the back of the unit. A valve amplifier must never be operated without a suitable load at the speaker terminals. Make sure there is a good electrical connection between the terminals and the resistor. Bias current calibration This calibration does not require a measuring instrument, as the bias level of each tube can be displayed on the LED scale. The four dipswitches allow valve selection, while each valve has its own trim potentiometer. RV1 controls V1, RV2 controls V2 etc… IMPORTANT : This calibration determines the bias current trough the expensive output valves. Therefore, it requires your absolute attention. Perform the calibration in the correct order. No signal may be present at the input of the amplifier, during the calibration. Flip all four DIP switches (SW2) to their OFF position Every switch enables the bias readout of one valve, so do not switch on more than one at a time, or the readout will be incorrect. Reconnect the mains plug, and switch the unit ON again (switch in full upward position) Wait until LD2 lights green continuously. Put the first switch in the ON position (use a pen or a small screwdriver) Gently turn RV1 clockwise until the second or third LED lights (LD4 or LD5) Switch off the first switch. Switch on the second switch Gently turn RV2 clockwise until the second or third LED lights (LD4 or LD5) Perform the same operation with RV3 and RV4 Wait for about 10 minutes, before continuing the rest of the calibration. Repeat the calibration of RV1 to RV4, but this time the trim potentiometers must be turned clockwise until one or two green LEDs light. 22 __________________________________________________________________________________________________________________________________________________________ When this operation is finished, check the 3.6V DC voltages at R65, R66, R70 and R71. Again, use J4 as ground reference. FINALLY ! It is time to listen to your amplifier ! Switch off the unit completely before connecting or disconnecting any cables. Connect a 4 or 8 ohm speaker to the correct terminals at the back of the unit. Speakers with impedances between 4 and 8 ohms can be connected to the 8 ohm terminal. The common negative speaker terminal is located in between the 4 and 8 ohm positive terminals. Hook up an audio source to the RCA connector at the back. Make sure the volume control of the source is set to minimum before the unit is turned on. The ‘SENSITIVITY’ trimmer located at the centre of the board allows you to trim the amplifiers input sensitivity, so two units put out exactly the same level, which improves the stereo image. Normally, this trimmer should be set fully clockwise. If necessary, feed a mono signal to both amplifiers, and trim both sensitivity trimmers, until the sound comes from the exact centre between both loudspeakers. • Valve amplifiers run hot ! Operate them in a well ventilated area ! Do not put them in a closed rack, stack or cabinet. • It is a good habit to check the bias current on a regular basis, especially when the valves are new. • They need to run-in for a while, during which the bias level may shift. • For short intervals between listening sessions, put the amplifier in stand-by mode (mains switch in middle position). FINISHING THE ENCLOSURE ASSEMBLY • Check if none of the components on the PCB will touch the chromed cover plates, when they are put in place. • Turn the unit, so it rests on its left or right hand side. • This allows you to fasten the bottom lid, by means of the supplied black button head hexagon socket screws. • Click the caged nuts into their holes on the chromed vertical plate (Be careful not to scratch the surface). • Mount the chromed cover plate on the chromed vertical plate with two silver button head hexagon socket screws. Tighten by hand. • Position this assembly onto the enclosure, and put the silver button head hexagon socket screws in place. Tighten them by hand. Connect the chromed vertical plate to SK22 (chassis earth) with a length of yellow/green striped wire and 2 female push-on terminals. Make sure you solder both terminals. (See fig 5) • Mount the top cover on the enclosure (Make sure the earth lead of the vertical plate is bent down, so it does not get squeezed between the lid and the enclosure). Use the supplied black button head hexagon socket screws. • Mount the front panel. Use the supplied right angle mounting brackets, together with the shakeproof washers and the M3 and M4 bolts. Take care of the correct position of the mains switch and LD2. • Make sure everything fits well, and tighten all screws. ! THIS AMPLIFIER RUNS HOT , OPERATE IT OUT OF THE REACH OF CHILDREN ! CHECK YOUR MAINS VOLTAGE MAKE SURE IT MATCHES THE SELECTED VOLTAGE REMOVE T HE MAINS PLUG AND WAIT AT LEAST 15 MINUTES BEFORE REMOVING THE COVERS SOME PARTS MAY CARRY DANGEROUS VOLTAGES, EVEN WHEN THE UNIT IS UNPLUGGED TROUBLESHOOTING 23 _________________________________________________________________________________________________________________________________________________ ______ Hum coming from the speakers : To make sure the amplifier is the source of hum, short the RCA input (by means of a spare male RCA plug, which you short internally), and disconnect the earth connector SK21. As a reference, listen at about 1m (3 ft) from the speaker, there should be an negligible amount of hum present. If there’s still a reasonable amount of hum present, check the bias current of every valve. Also check the electrical connection between the PCB ground and the enclosure, which is done trough the bolt next to R1. A defective valve can also be a source of hum. If hum is only present, when the amplifier is hooked up to an audio system, then a hum-loop could be the cause. To verify if this is the case, disconnect SK21 Use good quality, as short as possible, interconnecting leads. For best results, choose equal lengths for both left and right amplifier. If the high tension is not present, check the transformer wiring and the mains fuse, located at the back of the unit, below the mains inlet. An intermitted crackling sound coming from the speakers could point to a defective resistor R62. Replace it with the same value and power rating. A continuous buzzing sound coming from the speakers or a crackling sound during bass peaks could be caused by oscillation of the amplifier. In this case, try raising the value or R46 (e.g. 2K7 or even 3K3). This will also slightly increase the input sensitivity. If your speaker system includes a piezo driver, make sure it has a 10 ohm/ 1W resistor in series with the unit. THE MODIFICATIONS MENTIONED ABOVE ARE ONLY TO BE PERFORMED WHEN REPEATED INSPECTION OF THE CIRCUIT BOARD, SOLDER JOINTS AND WIRING DID NOT POINT TO ANY OBVIOUS FAULT S OR MIST AKES OF ANY KIND. REMARK: Valves are very sensitive to mechanical shocks. Therefore, we recommend not to move the unit when the valves are hot. Always let them cool down for a while. Avoid sudden temperature changes, e.g. when the unit is moved from a cold room to a heated room. Always leave it idle for a while, so it can adapt to the new environmental condition. A valve that breaks down starts glowing cherry red. Turn off the unit immediately. Usually, the 47 ohm/1W cathode resistor of the defective valve will also need replacement. If you have the impression that for some reason, the unit still does not operate as it should, you can send it to our technical dept. for inspection. Send the PCB only, not the enclosure or the transformers. Use the original box. Include a detailed description of the fault. Check www.velleman-kit.com for your nearest Velleman dealer. Velleman wishes you many hours of listening pleasure ! 24 __________________________________________________________________________________________________________________________________________________________ DIAGRAMS 25 _________________________________________________________________________________________________________________________________________________ ______ PCB C1 SK11 R1 SK21 C2 R3 R4 R5 R2 D1 ZD1 T1 C14 R6 R7 RY1 1 T2 D2 C16 D3 R55 D6 J6 SK15 D TRAFO1 L 2x J22 C20 RY4 VOLTAGE SELECTION1 0 SK12 C B SELECTIO N2 D9 D11 D10 D12 395VDC D28 R73 C30 f6 C31 SK10 GREEN D13 D14 R43 D15 D16 SK7 SK8 f7 C28 f8 C23 HIGH VOLTAGE INDICATOR LD13 C22 12VDC D19 D17 f2 GRAY 6.3VAC f3 f4 GRAY R10 D20 J13 J15 J14 R61 J3 2x 300VDC R75 R74 D18 f1 J12 C25 6.3VAC J10 C19 C24 R40 GREEN SK9 f5 C29 R41 R42 R58 2x J2 ZD2 T4 SK6 J8 D30 D7 J11 SK5 390VDC D29 R8 F1 2x D27 R9 C21 SK4 BLUE RED YELLOW FROM OUTPUT TRANSFORMER J1 R57 A FROM POWER TRANSFORMER VOLTAGE 100V N R56 SK14 RY3 D8 120V SK3 4 Ohm GND 8 Ohm TO LOUDSPEAKER TERMINALS R59 A 230V 12VAC J9 100-120V/8A Slow 230-245V/4A Slow AC POWER SK2 RED RED SK1 SK13 R60 YEL LOW BLACK YELLOW BROWN BLUE ORANGE A: 100VAC B: 120VAC C: 230VAC D: 245VAC J7 J5 B 245V VIOLET D C C18 T3 RY2 SK22 A: 100VAC B: 120VAC C: 230VAC D: 245VAC C17 D4 D5 C15 J16 J17 ORANGE C5 R12 BROWN BLACK 1 RV5 80VDC 9 BLACK R49 C6 SK17 GREEN R19 R18 R13 220VDC R47 R16 R63 C3 100VDC 9 SK16 155VDC J18 SENSITIVITY R17 C4 R64 R11 R62 R44 1 R48 R14 R45 R15 R46 VIOLET FROM OUTPUT TRANSFORMER C11 R50 75VDC V5 190VDC V6 C12 J19 C13 V1 3 V4 J4 2x 4 C7 C8 K8010: 3.6VDC K8011: 0.4VDC 1 8 5 K8010: 3.6VDC R65 R20 K8011: 0.4VDC R66 5 8 4 1 TO POWER ON SWITCH 6 3 1 SK18 R68 1 VELLEMAN P8010'1 / P8011'1 R69 C9 2 DANGER HIGH VOLTAGE 3 2 4 K8010: 3.6VDC K8011: 0.4VDC 1 RED RED RED RED GREE N 1 D25 D26 R30 R31 C27 YELL0W -50VDC BIAS CURRENT ADJUST LD3 LD4 LD5 LD6 LD7 LD8 LD9 LD10LD11LD12 GREE N 3 J21 YELL0W 2 3 R27 SW2 YELL0W R2 8 R51 R5 2 RV2 R53 R54 8 YELL0W RV1 1 26 R26 4 SW1 1 LD2 5 R29 TO POWER ON LED SK20 R25 1 LD1 R24 5 R23 6 2 5 8 R71 VB2 R32 4 1 R36 R70 R22 3 K8010: 3.6VDC K8011: 0.4VDC 3 D24 1 R72 VB1 R33 R34 3 VB1 K8010: 1.6VDC K8011: 0.2VDC C26 IC1 VB2 K8010: 3.5VDC K8011: 0.45VDC RV3 RV4 R37 J20 V3 R35 D23 D21 D22 6 SK19 V2 1 5 3 C10 4 R67 R38 4 R39 2 R21 5 3 ! PCB CONNECTED TO MAINS HIGH VOLTAGE N MAINS L F1 4A SLOW @ 230/245VAC 8A SLOW @ 100/120VAC 0 1 100V A 2 115V B 3 230V C 4 245V 1N4007 D20 D19 1N4007 RY4 VR5V122C 470u C19 3V9 1N4148 OFF BC547C R75 15/5W 15/5W A B R2 220K 100u C15 +V 4u7 1N4148 D1 3V9 C16 C14 ZD1 470u 1N4007 D5 0 BLACK 100V BROWN 120V BLUE ORANGE 245V VIOLET GRAY 6.3V/7A GRAY GREEN 6.3V/7A GREEN YELLOW 50V/0.1A YELLOW RED f1 f2 f3 f4 0 D11 1N4007 D12 D3 1N4007 R57 T3 1N4148 D6 R9 D10 BIAS4 BIAS3 BIAS2 1 2 3 4 D26 SW2 10M 1N4148 R31 330K/0.5W R54 330K/0.5W R53 330K/0.5W R52 330K/0.5W R51 47u/100V 100u/100V BIAS1 1N4007 -V C20 22K 15/5W R73 395VDC C21 1N4007 C28 39K/1W R60 C29 39K/1W R61 3K9 R30 1K5 R32 4.7 R34 12K RLO ADJ REF RHI SIG MODE 100u R33 NC D25 C26 4 8 7 6 5 9 14 13 12 2 V- 11 10 V+ 1 18 17 16 15 LM3914 IC1 3 +V 2.5 2.75 3 3.25 3.5 3.75 4 4.25 4.5 4.75 220u/450V 220u/450V 220u/450V C27 390VDC 39K/1W R59 1N4148 C17 SI 470u -50VDC 1N5408 1N5408 D9 D30 D28 D29 1N5408 VR10V121C RY2 1N4148 D4 D2 1N4148 T2 270/1W BC547C R55 10K/1W 10K/1W D27 1N5408 R56 1N4007 290 2K2 BC547C 2K2 R3 R4 220K BC516 T1 R5 290V/0.7A RED POWER TRANSFORMER C 230V D VR10V121C R74 T4 1K5 R22 GREEN RY3 1N4148 D8 L-93WEGW RED LD2 560 1K2 LD1 L-56BHD 1N4148 D23 R24 D24 STB 1N4007 D22 1N4007 R23 C18 470u ZD2 1K R8 470 D18 R1 1N4007 D21 ON SW1 12VDC 1N4007 D17 1N4007 D7 12VAC/2.5VA 7 9 TRAFO1 D 5 RED LD3 RED LD4 RED LD5 RED LD6 GREEN LD7 GREEN LD8 RED LD9 RED LD10 RED LD11 RED LD12 12K/1W R58 LD13 RED +V1 100u/400V C30 +V2 300VDC __________________________________________________________________________________________________________________________________________________________ DIAGRAM POWER SUPPLY SECTION 27 _________________________________________________________________________________________________________________________________________________ ______ DIAGRAM AMPLIFIER SECTION 28 SI GND INPUT IN C2 6 2 13 100p GREEN 6.3VAC GREEN VR05R121A RY1 47n C1 1K R7 R48 f4 220/.5W R40 R50 9 4700u C23 3.3/.5W 1000u C22 5 6 1N4007 D13 D14 3 2 R10 4 1 1N4007 C24 47K 220/.5W GRAY 6.3VAC f2 220/.5W R45 220/.5W f1 1K R15 680n/160V C13 C11 680n/160V 80VDC R44 27K/.5W R47 R16 680 R49 C12 R62 V5 1M 5 6 2K2/.5W R46 8 7 ECC81 C3 4 1 C4 330p 47K/1W R64 3 2 47K/1W R63 f2 f1 9 300VDC 100K/1W R14 330p/400V 3K9 R11 110VDC 155VDC 680n/160V R18 500K 470K R17 47u/350V RV5 GRAY C6 68n/630V 47K/.5W R42 D16 D15 1N4007 1N4007 8 7 ECC82 V6 100K/.5W 3K9 220/.5W R43 f3 R41 100K/.5W R19 220/.5W 7 8 1 14 100K R6 47u/350V C25 190VDC +V2 1M 100K R37 RV3 100K -V R13 75VDC 1K5 R12 C5 68n/630V 220VDC 100K R27 RV2 100K -V R35 -V 100K R39 RV4 100K C8 68n/630V 220K C7 68n/ 630V C10 68n/630V C9 68n/630V 100K R25 RV1 100K 220K R38 10K R20 10K R36 10K R29 220K R28 10K R21 220K R26 -50VDC 180/1W R67 4 5 V4 KT88 5 4 R68 180/1W 2 3 7 f3 f4 1 8 8 1 V1 KT88 7 f1 f2 2 3 KT88 5 4 3.6VDC 180/1W R72 4 5 BIAS3 V3 47/1W R66 47/1W R65 BIAS1 3.6VDC R69 180/1W f1 f2 2 3 7 1 8 8 1 V2 KT88 7 f3 f4 2 3 3.6VDC BIAS4 47/1W R71 +V1 390VDC 47/1W R70 BIAS2 3.6VDC VIOLET GREEN BLACK BLACK BROWN ORANGE LS ZD043 TRANSFO3 GND RED YELLOW BLUE GND 4 Ohm 8 Ohm __________________________________________________________________________________________________________________________________________________________ 29 _________________________________________________________________________________________________________________________________________________ ______ 30