FM Towns Marty

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IC Information

Main PCB: CA20142-B21X

  • M90: LC7881M (might be installed on add-on PCB, see below)
  • M91: TL084 (might be installed on add-on PCB, see below)

Add-on DAC PCB: CA20137-B06X (on top of IC M14)


CDROM PCB: CA02950-0319

Common Problems

Floppy drive does not function properly 
Floppy drive belt has probably stretched. New belts are available here.


Capacitor List

Power Supplies

Tamura Power Supply

Purchase these parts as a kit

C5	100uF	200v
C6	100uF	200v
C7	4.7uF	400v
C13	680uF	16v
C14	120uF	16v
C15	1800uF	10v
C16	1800uF	10v
C17	120uF	16v
C18	100uF	35v
C19	47uF	35v


Eastern Power Supply

Purchase these parts as a kit

Most designators unknown - third column is quantity
680uF	10v	4
470uF	16v	2
120uF	25v	2
4.7uF	35v	1
1uF	50v	1
180uF	200v	1


Main PCB CA20142-B21X

Purchase these parts as a kit (Main + CDROM PCB)

FM Towns Marty capacitor map
C1	100uF	16v
C2	47uF	16v
C3	100uF	16v
C4	100uF	16v
C5	100uF	16v
C6	33uF	16v
C7	100uF	16v
C8	2.2uF	50v
C9	100uF	16v
C10	33uF	16v
C11	100uF	16v
C12	33uF	16v
C15	10uF	16v
C16	10uF	16v
C17	47uF	16v
C18	47uF	16v
C19	100uF	16v
C21	33uF	16v
C22	470uF	10v
C24	33uF	16v
C26	1uF	50v
C27	1uF	50v
C28	100uF	16v
C29	100uF	16v
C30	100uF	16v
C31	100uF	16v
C32	10uF	16v
C155	EMPTY	
C170	0.47uF	50v
C171	0.47uF	50v


CDROM PCB CA02950-0319

C2	100uF	6.3v
C4	100uF	10v
C5	330uF	6.3v
C7	100uF	6.3v
C8	100uF	6.3v
C10	100uF	6.3v
C12	100uF	16v
C13	4.7uF	50v BP
C14	47uF	6.3v
C15	47uF	6.3v
C16	EMPTY	
C17	1uF	50v
C18	1uF	50v
C19	22uF	16v
C20	330uF	6.3v


Floppy Drive PCB

220uF	6.3v