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Summary of Contents for Project 80

Page 1: ...I llnEl lr PROJECT 80 Constructional andtechnical information onSinclair project80modular high fidelityamplif iersystem tl...

Page 2: ...ormance Connections SeeSection86 Tunersotherthan P80 Tape recordlng Commonfaults Alignment ControlModulesStereo80 and AFU Stereo80 Circuitdescription Circuitdiagram Layout Performance Connections Powe...

Page 3: ...9 29 2q 30 30 30 30 30 30 Apology We regret that due to circumstances beyond our control the layout and design of this first edition of the Project 80 manual has been rushed We apologise for any resul...

Page 4: ...hardware etc to suit their cabinets or your localshopshouldbe ableto supplyallthe required items AB3 Notes l The Z40s are mounted on heatsinkblocks as shown in 41 2 The nuts and bolts indicatedabove a...

Page 5: ...gs A 5 4 1 8 6 AC3 Notes 1 The plinthwe use in this exampleis the BSR McDonaldAp1 suitablefor HT70 MP60and 610decks lt measures405x 370 x 88mm approx When choosingan alternativeplinth make sure it ist...

Page 6: ...them all before startingassembly Item Ouantity Description 1 Masterlink 1 ProjectB0preamplifier 1 PZ5power supply 2 240amplifiers 1 Mainsswitch unit with wires Wires items6 to 13areallpackedin one ba...

Page 7: ...hers I 3 684 nuts tormounting 3 684 shakeproof washers I preamplifier 1 eachitems as19formountinq switch unit 2 Anglebrackets r 8 684 screws I 8 68 4nut formounting 201 211 221 z J l 8 684 nuts I mast...

Page 8: ...e deck manufacturer lf you are not using them cut them off com pletely Adding tuner decoderand AFU can be done using the extra wires items15 17 Connections for these extra modulesare asshownin AB1 AFU...

Page 9: ...he power amolifiersshould be mounted on metal for heat dissipation Seesections 43 2 and D6 3 Severalcommercially available cabinetsare available for project 80 addresses of suppliers aregivenin sectio...

Page 10: ...o the L 1 0 connection on the PZ5 or 6 or to the 240 volt input on the PZ8 transformer MainsNeutralconnectsthrough the second pole on the switch to N on the PZ5 6or to Ov on the transformerprimaryof t...

Page 11: ...dicator LED Indicators are now readilyavailable These work Jrom dc so must be connectedbetween tve the power supply via a suitable lirniting resistor and earth A currentof about 20mA is suitablefor mo...

Page 12: ...rth c Both channels work the preamplifier isat fault The 740 260 or its wiring is at fault Exchangeall wiring from leftZ40 onto the right hand 240 and vice versa a faultisnow on otherspeaker thenthis2...

Page 13: ...ules 270 l2w 86 3 Low VoltageUse 1 l 22v wellsmoothed may befed intopoint2 11 17voltsuseis possible if the followingmodifications aremade 1 Replace D2 tuner or D1 decoder by a 9v 1w zenertakingcare to...

Page 14: ...eof the signalin the detectorcircuitand shouldbe sei to givea symetrical S curvewith a F M sweepsignalapplied lcl hai a limitingcircuitbeforethe detectorstagewhich providesa very good degreeof a m rej...

Page 15: ...tations This should vanish when a station of good strength is tuned in lt can be reduced howeverby mountingthe tuneron a metalplate or liningthe front of the wood panel with metal foil beneath an insu...

Page 16: ...ptionimpossible A poor 1F strip will invari ably resultin poor separation It isnot possible to supplydetailed conversion instructions for any particular tunerand the conversion can sometimesbe very di...

Page 17: ...TRl is a virtual earthstagewith C4 C5 R5and R6 as feedback comDonents andR1in series with the inductance of the magnetic pick up as the sourceof impedance The circuitin fact utilises the inherantprope...

Page 18: ...input has a sensitivity of 100mVand the tape 30mV Almost every signalsource you may wish to usewill feed one or other of these inputs but if you wish to reducethe sensitivityof eitherone the alternat...

Page 19: ...R7 and C6 r I CB2 AFU circuit C86 Power supply TheAFU will operatefrom below 12Vto 50V The maximumoutput isvoltagedependant and if clippingoccursat lowervoltagesR7 can be reducedto 6K8 or so lf the AF...

Page 20: ...n batterya 5 pole2 way switch could be used for this override the spare pole being used to switch off the AFU CB B I AFU wired for tape socket CONNECTIONS TO A F U c B 8 1 6 P I N D I N P L U G VIEWED...

Page 21: ...You will alsoneed betterheatsinking where the amplifieris used for high powersratherthan the for normaldomesticuse As a test of your heatsinking feelthe blackfin of the amplifier lf this underallcondi...

Page 22: ...ould be able to supply the current indicated above For battery operationthe capacitorshown as C3 in D5 must be included but itsvalueshould be increased 1000pF isto be considered the minimum value but...

Page 23: ...cessive leadlengthsor layouts which placeoutputsand inputstoo closetogether DA Z4O DAl TechnicalDescription Theinputsignalisapplied to Tr1 sbase whichcomparesit with part of the outputand amplif iesth...

Page 24: ...ermissible load impedance 4 8 or 16t Protection safeooencircuit 3A currentlimitintolow imoedance Dampingfactor 50with 8fl load Powerbandwidth 30Hzto 35KQHz 3 db Inputsensitivity 90 mV for 12wintoBl DA...

Page 25: ...w Caremust be takenwith the wiring which shouldbe as short as possible Fig D89 2 2shows the wiring of the bridge with the two amplifiersmounted aboul 1 2 to 1 apart oneof the heatsinkblocks shown in f...

Page 26: ...S6 Inputs Fig DB9 4 2 a b show two input circuits a is a virtual earth invertingmode input and the gainwill be approximately Zf 100K R4 b is a non invertinginput which shouldbe usedfrom a low source i...

Page 27: ...To test the circuit disconnectit I outputs replaceFS1 by a 1aslow blow and switch on with a voltmeteracrossthe output The voltage will rise quickly to about 15v and will then slow down stopping at 35v...

Page 28: ...t the same time if the output voltage is at its nominal value of 50v T16isturned hard on by the referencedevelopedon its baseby R10 and R11 The tail currentthrough the differential pair is then limite...

Page 29: ...4 The curve shows the re entrantcurrent limitingon the PZ8 Mark 111 and how this behaveswith a resistiveload Refer to the technical description for moreinformation At A the circuithasswitchedon and st...

Page 30: ...ut It alsohasalternative connections by meansof push fitwires for pickup when the whole projectis to be plinth mounted Facilities arealsoprovidedfor connectionof headphones The masterlinkalsocontainsd...

Page 31: ...TOP a a Y r AFU Templates TOP I Tuner Removeareamarked whenmountinoon metal Switch Unit TOP Masterlink rr o n TOP 6mm d Y rh r Preamp f tfr holes 7e 3mm Theseholest 5mm Q 1...

Page 32: ...writtenby Richard J Torrens illustrated by StanNorth Publishedby SinclairRadionicsLtd London Road St lves Hunts PE17 4HJ Designedand Printedby Photo PrecisionLtd St lves Hunts Publicationnumber TFOI...

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