- Serial Numbers
- Parts List/Modification History
- Retrospective (Mandatory) Modifications
- Notes to Tables
1. SERIAL NUMBERS
1.1 The serial number is visible on a label attached to the underside of the Sinclair QL thus: D13 59643. Prefix D13 relates to the build standard (B/S) and Issue Number, 59643, is the number of the production run.
2. PARTS LISTS / MODIFICATION HISTORY
2.1 Parts lists for the Sinclair QL are presented in tabular form. They cover p.c. board Issue 5 (build standard D6 to D13) and p.c. board Issue 6 (build standard 14 and beyond). The Issue 6 p.c. board introduces a number of relatively minor circuit changes from Issue 5. These are illustrated in Figures 5.1 and 5.2 and itemised in Tables 5.1 to 5.5 under separate columns labelled Issue 5 and Issue 6.
2.2 Items listed on Issue 5 relate to build standard D13, incorporating the latest version firmware (i.e. 32k and 16k JM masked ROMs in IC33, IC34 respectively). Earlier build standards (D6 to D10) saw the progressive introduction of improved firmware starting with a pickaback 16k EPROM replacing the external 'dongle'. A history of these early units is tabulated below.
BUILD STANDARD | IC33 | IC34 | MASK |
D6 | 2 x 16k EPROM | 16k EPROM | AH |
D7 | 2 x 16k EPROM | 16k EPROM | JM |
D8 | 32k ROM | 16k EPROM | AH |
D9 | 32k ROM | 16k ROM | AH |
D10 | 32k EPROM | 16k EPROM | JM |
D11-D14 | 32k ROM | 16k ROM | JM |
2.3 Build standard D12 saw the introduction of modifications to the microdrive circuits foil owed by a new microdrive cartridge chassis at build standard D13. The JM version ROM firmware and microdrive improvements were carried out to Issue 6 (build standards D14, D15).
3. RETROSPECTIVE (MANDATORY) MODIFICATIONS
3.1 In order to improve performance and reliability the following components must be added/replaced on all pre-build standard 12 QLs returned for repair (see Section 4).
- R104 (82 Ω) introduced in TR1 collector circuit.
- R92 (formerly 220 Ω) increased to 390 Ω.
- R105/R106 (1 kΩ) introduced across C19, D17.
- D22/D23 (1N4148) introduced in series with R100/R101.
- R102/R103 (33 kΩ) introduced between IC23 pins 21 and 19 and VM12 (-12 V rail).
- firmware (IC33, IC34) to be upgraded to build standard D11.
4. NOTES TO TABLES
- Early Issue 5 boards fitted with 43 kΩ resistors; do not replace unless it does not meet colour test criteria.
- Retrospective (mandatory) modification required - see sub-section 3 (above) and Section 4 - Fault Diagnosis and Repair.
- Fitted according to build standard and Issue.
- BC183P is alternative type - NOTE: leads are reverse of BC184.
- IC17 only fitted on Issue 5 EPROM versions.
- IC38 replaces IC27 on Issue 6 versions.
TABLE 5.1 GENERAL ASSEMBLY
Description | Manufacturer/Type |
QL Base Assembly |
| Microdrive Chassis (2 off) - Table 5.3 |
| Final PCB Assembly - Table 5.5 |
| Loudspeaker Assembly | 60 Ω, 23 mm, TV |
| Heatsink Assembly - Table 5.2 |
| Bottom Case Moulding |
| Bottom Case Fixings |
| 1/4-in self-tap (2 off) | PCB Fixings |
| Fibre washer (2 off) |
| 5/16-in self-tap (2 off) | MDV Fixings |
| 1/2-in self-tap (2 off) |
| 3/4-in self-tap (2 off) |
QL Keyboard Assembly |
| Yellow LED (D27) |
| Red LED - 2 off (D20, D21) |
| QL Membrane |
| Keyboard Backplate |
| Keyboard and Bubble Mat |
| Keyboard Assembly Fixings |
| Adhesive Cable Clip |
| Double-sided Tape (0.5-in wide) |
| 1/4-in self-tap - keyboard backplate |
| ROM Cartridge Bung |
| MDV Extension Bung |
| BUS Extension Bung |
| General Assembly Fixings |
| 5/16-in self-tap (4 off) | Keyboard/Base |
| 1 1/4-in self-tap (4 off) |
TABLE 5.2 HEATSINK ASSEMBLY
Description | Manufacturer/Type |
Heatsink | Wakefield Mk.2 |
| +5V Regulator (IC35) | 7805 |
| 3-pin connector | Molex, 4025 |
| Heatsink Fixings |
| M3 x 10 mm pan hd screw | 1-off |
| M3 plain washer | 1-off |
| M3 crinkle washer | 1-off |
TABLE 5.3 MICRODRIVE CHASSIS
Description | Manufacturer/Type |
Microdrive Cassette Chassis Assembly |
| Cassette Chassis |
| Motor Assembly |
| Microswitch Assembly |
| Drive Roller (parallel) |
| Plastic Roller |
| Cassette Chassis Fixings |
| M2.5 x 4 csk self-tap, motor fixings |
| 2,28 x 3/5-in self-tap, microswitch fixing |
Microdrive PCB Assembly - Table 5.4 |
| PCB Fixings |
| No. 4 x 5/16-in self-tap (2 off) |
| Fibre Washers (2 off) |
ULA Screen |
TABLE 5.4 MICRODRIVE BOARD
Circuit Ref | ISSUE 5 | ISSUE 6 | Notes | Rating/% Tol | Manufacturer/Type |
MDV1 | MDV2 |
CAPACITORS (all axial types unless otherwise stated) |
C5 | C6 | 330 pF | As Issue 5 | | 2.5% | HS30, Suflex |
C9 | C10 | 0.47 F | | 35V | ITT |
C11 | C12 | 0.22 F | | 35V | ITT |
C13 | C14 | 330 pF | | 2.5% | HS30, Suflex |
C15 | C16 | 220 pF | | 2.5% | HS30, Suflex |
C17 | C18 | 220 pF | | 2.5% | HS30, Suflex |
C49 | C50 | 47 nF | | 50V | |
C51 | C52 | 47 nF | | 50V | |
DC28 | DC29 | 100 F | | 50V, 10%+80% | |
RESISTORS |
R34 | R35 | 330R | As Issue 5 | | 5%, 1/4W | |
R36 | R37 | 330R | | 5%, 1/4W | |
R38 | R39 | 4K7 | | 5%, 1/4W | |
R40 | R41 | 4K7 | | 5%, 1/4W | |
R42 | R43 | 4K7 | | 5%, 1/4W | |
R44 | R45 | 4K7 | | 5%, 1/4W | |
R100 | R101 | 2K2 | | 5%, 1/4W | |
DIODES |
D12 | D13 | 1N4148 | As Issue 5 | | | |
D14 | D15 | 1N4148 | | | |
D22 | D23 | 1N4148 | (2) | | |
INTEGRATED CIRCUITS |
IC29 | IC30 | 2G007-Issue 3 | As Issue 5 | | ULA | Ferranti |
IC31 | IC32 | 78M05 | | +5V Regulator | |
MISCELLANEOUS |
HBC1 | HBC2 | A10021 | As Issue 5 | 2-off each | | 7-way flex. connector/cable |
TABLE 5.5 FINAL BOARD ASSEMBLY
Circuit Ref | ISSUE 5 | ISSUE 6 | Notes | Rating/% Tol | Manufacturer/Type |
CAPACITORS |
C1 | 32 pF | As Issue 5 | | 5% | Ceramic |
C2 | 22 pF | | 5% | Ceramic/TB |
C4 | 4.7 pF | | 25V, -10%+50% | Electrolytic/Axial |
C19 | 47 nF | | 50V | |
C20 | 47 nF | | 50V | |
C21 | 22 µF | | 16V | Electrolytic/Radial |
C22 | 22 pF | | 16V | Electrolytic/Radial |
C23 | 22 pF | | 16V, -10%+50% | Electrolytic/Axial |
C24 | 22 pF | | 16V, -10%+50% | Electrolytic/Axial |
C25 | 22 µF | | 16V, -10%+50% | Electrolytic/Axial |
C26 | 0.01 pF | | 20% | Ceramic/TB |
C27 | 0.1 pF | | 50V, -20%+80% | |
C28 | 0.1 µF | | 50V, -20%+80% | |
C29 | 220 pF | | 10% | |
C30 | 220 pF | | 10% | |
C31 | 16 pF | 22 pF | | 5% | Ceramic |
C32 | 0.01 µF | As Issue 5 | | 20% | Ceramic/TB |
C33 | 0.1 µF | | 50V, -20%+80% | |
C34 | 47 pF | | 5% | Ceramic/TB |
C35 | 100 µF | | -10%, +80% | Electrolytic/Axial |
C36 | 47 nF | | 50V | |
C37 | 470 pF | | 25V, -10%+50% | Electrolytic/Axial |
C38 | 4.7 µF | | 16V | Electrolytic/Radial |
C39 | 470 µF | | 25V | Electrolytic/Radial |
C40 | 4.7 pF | | 16V | Electrolytic/Radial |
C41 | 0.33 pF | | 50V | Electrolytic/Radial |
C42 | 47 pF | | 10V | Electrolytic/Radial |
C43 | 0.1 µF | | 50V, -20%+80% | |
C44 | 0.1 µF | | 50V, -20%+80% | |
C45 | 1 nF | | 2% | Ceramic |
C46 | 0.1 µF | | 50V, -20%+80% | |
C47 | 22 µF | | 16V | Electrolytic/Radial |
C48 | 0.01 µF | | 20% | Ceramic/TB |
C53 | NOT USED | 22 pF | | 5% | Ceramic |
DC1-29 | 0.1 pF | 0.1 µF | | 50V, -20%+80% | |
RESISTORS |
R1-R6 | 3K3 | As Issue 5 | | 5%, 1/4W | |
R7 | 330R | | 5%, 1/4W | |
R8 | 47K | | 5%, 1/4W | |
R9 | 3K3 | | 5%, 1/4W | |
R10 | 680R | | 5%, 1/4W | |
R11 | 1K | | 5%, 1/4W | |
R12 | 3K9 | | 5%, 1/4W | |
R13 | 10K | | 5%, 1/4W | |
R14 | 47R | | 5%, 1/4W | |
R15 | 330R | | 5%, 1/4W | |
R16 | 330R | | 5%, 1/4W | |
R17-24 | 10K | | 5%, 1/4W | |
R25 | 180R | | 5%, 1/4W | |
R26 | 3K3 | | 5%, 1/4W | |
R27 | 3K3 | | 5%, 1/4W | |
R28 | 1K | | 5%, 1/4W | |
R29 | 1K | | 5%, 1/4W | |
R32 | 820R | | 5%, 1/4W | |
R33 | 820R | | 5%, 1/4W | |
R46 | 1K | | 5%, 1/4W | |
R47 | 2K2 | | 5%, 1/4W | |
R48 | 8K2 | | 5%, 1/4W | |
R49 | 8K2 | | 5%, 1/4W | |
R50 | 8K2 | | 5%, 1/4W | |
R51 | 1K | | 5%, 1/4W | |
R52 | 1K | | 5%, 1/4W | |
R53 | 1K | | 5%, 1/4W | |
R54 | 47K | (1) | 1%, 1/4W | |
R55 | 2K2 | | 1%, 1/4W | |
R56 | 6K8 | | 5%, 1/4W | |
R57 | 11K | | 5%, 1/4W | |
R58 | 55K6 | | 5%, 1/4W | |
R59 | 22K | | 5%, 1/4W | |
R61 | 15R | | 5%, 1/4W | |
R62-69 | 3K3 | | 5%, 1/4W | |
R70 | 1M | | 5%, 1/4W | |
R71 | 2K2 | | 5%, 1/4W | |
R72-79 | 33R | | 5%, 1/4W | |
R80 | 15M | | 0.5W | |
R35 | 100R | | 5%, 1/4W | |
R86 | 270R | | 5%, 1/4W | |
R87 | 1K | | 5%, 1/4W | |
R88 | 75R | | 5%, 1/4W | |
R89 | 1K | | 5%, 1/4W | |
R90 | 1K | | 5%, 1/4W | |
R91 | 47K | | 5%, 1/4W | |
R92 | 390R | (2) | 5%, 1/4W | |
R93 | 3K3 | | 5%, 1/4W | |
R94 | 3K3 | | 5%, 1/4W | |
R95 | 1K | | 5%, 1/4W | |
R96 | 2K2 | | 5%, 1/4W | |
R97 | 1K | | 5%, 1/4W | |
R98 | 4K7 | | 5%, 1/4W | |
R99 | 2K2 | | 5%, 1/4W | |
R102 | 33K | ZERO Ω | (2) | 5%, 1/4W | |
R103 | 33K | ZERO Ω | (2) | 5%, 1/4W | |
R104 | 82R | 82R | (2) | 5%, 1/4W | |
R105 | 1K | 1K | (2) | 5%, 1/4W | |
R106 | 1K | 1K | (2) | 5%, 1/4W | |
JU1-6 | ZERO Ω | - | (3) | | |
DIODES |
D1-D17 | 1N4148 | As Issue 5 | | | |
D20 | LD235R | | RED LED | SIFAM |
D21 | LD235R | | RED LED | SIFAM |
D25 | BA157 | | | |
D26 | BA157 | | | |
D27 | LD235Y | | YELLOW LED | SIFAM |
D28 | 1N4148 | | | |
D29 | 1N4148 | | | |
TRANSISTORS |
TR1 | BC184 | As Issue 5 | (4) | | |
TR2 | ZTX510/BSX29-SGS | | | |
TR3 | BC184 | (4) | | |
TR4 | BC184 | (4) | | |
TR5 | RC184 | (4) | | |
TR6 | ZTX551 | | | |
TR7 | ZTX551 | | | |
TR8 | ZTX313/MPS2369 | | | |
TR9 | ZTX313/HPS2369 | | | |
INTEGRATED CIRCUITS |
IC1-16 | HM4864P-2 | As Issue 5 | Alternatives | | Hitachi |
TMS4164-15NL | | Texas |
MCM6665AP15 | | Motorola |
MK4564N15 | | Mostek |
UPD4164C-3 | | NEC |
MSM3764-15RS | | OKI |
TMS4146-12NL | | Texas |
HYB4164P2BD | | SIE |
IC17 | 74LS00 | (5) | | |
IC18 | MC68008 | | | Motorola |
IC19, IC20 | 74LS257 | | | NOT Nat. Semi |
IC21 | 74LS245 | | | NOT Nat. Semi |
IC22 | ZX8301 | | | Plessey/Sinclair |
IC23 | ZX8302 | | | NCR/Sinclair |
IC24 | 8049 | | | NEC |
IC25 | 1488 | | | |
IC26 | 1489A | | | |
IC27 | 74LS03 | | | |
IC28 | MC1377P | MC1377P | | | Motorola |
IC33 | | 23256 | (2) | | 32k ROM, JM Mask |
IC34 | 23128 | 23128 | (2) | | 16k ROM, JM Mask |
IC36 | 79L12 | 79L12 | | | -12V Regulator |
IC37 | 78L12 | 78L12 | | | +12V Regulator |
IC38 | - | HAL16L8 | (6) | | Sinclair |
CONNECTORS |
J1 | 64-way | As Issue 5 | | | Viking, Euro connector A/B |
J2 | 30-way | | | Edge connector |
J3, J4 | 603A LH | | | BICC, BT type |
J5, J6 | 603A RH | | | BICC, BT type |
J7 | Jack | | | 8-pin DIN |
J8 | 3-pin Skt | | | Phillips, Mains |
J9, J10 | Jack | | | Single pol, NC |
J11 | TE9FS/18B | | | 9-way flex |
J12 | TE11FS/18B | | | 11-way flex |
HBC1/2 | | 4 off | | Aries, 7-way flex. socket |
LS | MWP2P-1B | | | Burndy |
LEDS (D20, D21, D27) | MWP6P-1B | | | Burndy |
MISCELLANEOUS COMPONENTS |
TC1 | 540pF | As Issue 5 | | | Trimmer |
M1 | UM1233 | | | Astex, E36 Modulator |
X1 | HC18-U | | | 15MHz, 20ppm |
X2 | MX38 | | | 32.768kHz, 20ppm |
X3 | HC18T-U | | | 4.4336MHz, 20ppm |
X4 | - | | | 11MHz, 10ppm |
S3 | RESET | P/B Switch | | Schadow, DPCO |
FIGURE 5.1 PRINTED CIRCUIT BOARD (Issue 5) COMPONENT LAYOUT
FIGURE 5.2 PRINTED CIRCUIT BOARD (Issue 6) COMPONENT LAYOUT