Sinclair Spectrum

The famous ZX Spectrum from Sinclair Research introduced in 1982

For more information, see this article's corresponding Wikipedia page: ZX Spectrum.

Sinclair Spectrum

Preliminary Information
Release Year	1982
Leak Risk	Medium
Batteries	None
Mounting Technology	Through Hole, Sockets
Capacitor Types	Aluminum Electrolytic, Ceramic, Polymer
Destructive Entry	No

Known Issues

Symptom or Problem Encountered

Causes

• Description of cause

Solutions

• Solution to the problem

Disassembly Notes

A Spectrum 48K is easy to disassemble:

Remove the five screws from the back. Carefully open the case then lift the front edge you will see the keyboard connections to the motherboard, ease these connections out because they are easily damaged. Note that if the Keyboard is the original it is likely to be non-functional.

Original Parts

Spectrum motherboard Issue 2.

Sinclair Spectrum issue 2 motherboard capacitors

Note the reversed polarity on the silk screen for capacitor C46.

Capacitor Specifications and Footprint Information

	Qty	Capacitance	Voltage	Mount	Diameter/Size	Height	Temp	Type	Brand	Series
C25,C28,C44,C47,C50,C65	6	22 µF	16 V	Axial	4.8 mm Dia.	12 mm	85 °C	Aluminum Electrolytic	Gelec
C27,C46	2	1 µF	50 V	Axial	4.8 mm Dia.	12 mm	85 °C	Aluminum Electrolytic	Gelec
C44,C45	2	100 µF	16 V	Axial	6.5 mm Dia.	16 mm	85 °C	Aluminum Electrolytic	Gelec

Replacement Parts

Spectrum motherboard Issue 2

Replacement Radial Capacitors

RefDes	Qty	Compatible Part Number	Order Links
C25, C28, C44, C47, C50, C65	6	860020372002	Digikey Mouser
C27, C46	2	860020672005	DigiKey Mouser
C44, C45	2	860010372006	DigiKey Mouser

If parts are not available or different selection is preferred, you can use the values in the Original Parts section to perform a parametric search.

Original Parts

Spectrum motherboard Issue 3

Sinclair Spectrum issue 3 motherboard capacitors

Capacitor Specifications and Footprint Information

RefDes	Qty	Capacitance	Voltage	Mount	Diameter/Size	Height	Temp	Type	Brand	Series
C25,C28,C34,C47,C50,C65	6	22 µF	25	Axial	4.8mm	12 mm	85 °C	Aluminum Electrolytic	Philips
C27,C46	2	1 µF	50 V	Axial	4.8 mm Dia.	12 mm	85 °C	Aluminum Electrolytic	Gelec
C44,C45	2	100 µF	16 V	Axial	6.5 mm Dia.	16 mm	85 °C	Aluminum Electrolytic	Gelec
C74	1	4.7 µF	50 V	Axial	4.8 mm Dia.	12 mm	85 °C	Aluminum Electrolytic	Philips

Replacement Parts

Spectrum motherboard Issue 3

Replacement Radial Capacitors

RefDes	Qty	Compatible Part Number	Order Links
C25, C28, C34, C47, C50, C65	6	860010472003	Digikey Mouser
C27, C46	2	860020672005	DigiKey Mouser
C44, C45	2	860010372006	DigiKey Mouser
C74	1	860020672008	DigiKey Mouser

If parts are not available or different selection is preferred, you can use the values in the Original Parts section to perform a parametric search.