ZX80 Parts List

This is a full list of discrete components required to build the ZX80 excluding any hardware such as power supplies, nuts and bolts etc.

Component Type Qty   Function
IC1 Z80A 1 Processor  
IC2 ROM 1 4K for ZX80, 8K for ZX81 ROM  
IC3/4 RAM 1 2K, 8K or 32K  
IC5 74LS373 1 8-bit transparent latch Latches character data
IC6-8 74LS157 3 2 to 1 multiplexers Routes CPU address lines or
character data into ROM
IC9 74LS165 1 Shift register. Used for video and
saving to tape.
IC10 74LS365 1 Tristate buffer, six-bits Keyboard (5-bit) and
tape input (1-bit) buffer
IC11,12 74LS00 2 AND gates  
IC13 74LS04 1    
IC14,15 74LS05 2 Open-collector buffers Forces nop codes above 32K
IC16 74LS10 1    
IC17 74LS32 1    
IC18,19 74LS74 2    
IC20 74LS86 1 XOR gates  
IC21 74LS93 1 Counter Counts character line (0 to 7)
IC22 7805 1 5V1A regulator  
D3-10 1N4148 8 Small signal diodes Address lines drive keyboard
X1 6.5 MHz Xtal 1 or ceramic resonator  
         
C1-6,12,13 47nF 8   C12,13 used for tape circuit
C8 22uF 1    
C9,11,14,15 47pF 4   C14 used for tape circuit
C10 1uF 1    
         
R1,
R3-11,18,
R12,22,23
R27,
R30,
R34
1K 16   R1 pulls down tape input
R3-11 isolate D0-7 from D0-7'
R12,22,23 pull-up unused Z80 lines
R27 in CPU clock driver
R30 used for video out
R34 used for tape circuit
R2,25 470R 2    
R12,   1    
R13-16,? 47K 6    
R19 2k2 1   Impedance in RAM /CS
R21 220K 1    
R29 180R 1    
R20
R32
330R 2   R20 pulls up the Z80 clock line
R32 used for video out
R35 1M 1   R35 used for tape circuit
         
SW1-40 SPST Push 40 For keyboard  
  Phono socket 1 For video out  
  3.5mm Jack Socket 2 For tape recorder  
  Vero Board 1 Perhaps 100 x 220 mm?  
  40 Pin DIL socket 1 For Z80A CPU  
  28 Pin DIL socket 1 For ROM  
  20 Pin DIL socket 1    
  16 Pin DIL socket 5    
  14 Pin DIL socket 11    
  Wire wrap cable      
MOD1 UM1233 1 UHF modulator