Batteries

Universal Power Supply

Key points

• Input voltage 90-264 VAC
• Input frequency 47-63 Hz
• Overcurrent protection All outputs protected to short circuit condition
• Operating temperature 0°C to +70°C, derate linearly above 40°C to 50% @ 70°C
• MTBF 100,000 hours minimum at full load at 25°C ambient
• EMI requirements Meets conduction limits of (a) FCC PART 15 CLASS B (b) CISPR CLASS B
• Safety Approvals UL/cUL60950, TUV/GS (EN60950)
• Size 91mm x 36mm x 38mm (3.6" x 1.4" x 1.5")

Overview

At last a small lightweight power supply for your Z88.

The Z88 does not physically switch to the power supply when being powered externally. Power from the internal batteries will only be saved if this power supply is used.The reason behind this is the Z88 runs on 6v, ( 4 x AA 1.5v batteries). A diode is used in the external supply circuit which drops the voltage by 0.8v. If the normal 6.5v Z88 Mains adapter is used for example, the voltage across the batteries will be

6.5 – 0.8 = 5.8v.

The batteries in the Z88 will be discharging until they reach 5.8v. This is about half their charge. The Universal Power Supply has an output voltage of 7v. This gives 6.2v across the batteries which ensures that they hold their charge.

When the Z88 came out the Mains adapters were built using large and heavy transformers, forcing users to either leave them at home or having two supplies, one for home and the other at work. This power supply is the modern lightweight equivalent .

Use it either in the USA, Europe or anywhere in the world.

Power on indicator		Stable Supply		Light weight		Fit the Plug yourself
See if it is plugged in		7v input ensures that your batteries are not used.		weighs only 250g (9oz)		Use it anywhere in the world.

Z88 Mains Adapter		Save your batteries whilst working at home with this 220v 2 - pin mains adapter. The 2 pin Euro plug can be cut off allowing an ordinary 13A UK (or any other) plug to be fitted if desired. Weight 550g
If you want to use a different power supply it must be regulated and have an output of 6.8v to 7.2v with the positive pin being in the middle. If you don't want to open it and you have a spare earphone, put that across the power output. If it buzzes like mad, it is unregulated, if you can't hear much of a sound it is either not connected, or it is regulated.

Ram Packs
Using Ram Packs with your Z88. Inserting the RAM pack into Slot 1 of the Z88 The Z88 comes with 32K RAM 'built-in' memory. This is used both as working memory and for storing files.		The Z88's memory can be expanded in 32K, 128K or 1M byte blocks by inserting a RAM Pack. A 1M RAM Pack has enough room for around 200 typed A4 pages. If power is lost, through the batteries going flat or if an application crashes, any files that or stored in RAM or unsaved current work may be lost. Cambridge Computer The Z88 Card Exchange System (864K) Cambridge Computer Memory Card booklet (500K)

1M Low Power RAM Card

This uses a modern static RAM chip which gives the following advantages:- 1M RAM Low Power Longer battery life. This is a RAM pack. If removed, a HARD reset is required

EPROM Erasers
		There are no EPROM Erasers left. The previous information on EPROM Erasers has been moved to the Archive section.

Z88 Dummy EPROM Case Use your Z88 EPROM Eraser to ERASE EPROMS.   The EPROM is placed in the carrier. When fully inserted into the eraser, the lamp is turned on. The sides have been removed to allow a 40 pin EPROM to be used.

Z88 Hardware

Description	Price	VAT	Total
Cable - Printer (Parallel)	£34.00	£6.80	£40.80
Cable - Printer (Serial)	£5.00	£1.00	£6.00
Z88 Dummy EPROM Case (Erase DIL EPROMS Using The Z88 ERASER)	£8.29	£1.66	£9.95
Card Case	£8.66	£1.33	£10.00
PCB (Blank)	£7.00	£1.40	£8.40
Carrying case	NONE LEFT
Flash EPROM (1M)	£45.83	£9.17	£55.00
Flash EPROM (1M) LED Upgrade	£15.00	£3.00	£18.00
Flash EPROM (512K) / 512K RAM	£49.17	£9.83	£59.00
EPROM Card (32K)	£16.67	£3.33	£20.00
EPROM Eraser	NONE LEFT
EPROM Card (128K)	£25.00	£5.00	£30.00
EPROM Card (256K)	£49.17	£9.83	£59.00
Rubber Keyboard Mat NO UK Version LEFT only foreign.	£25.00	£5.00	£30.00
Keyboard Membrane	£20.83	£4.16	£25.00
Mains Adapter (220v)	£8.95	£1.79	£10.74
Modem 300/1200-software & cable	NONE LEFT
Modem Cable?	£10.00	£2.00	£12.00
Power Supply (90-264v)	NONE LEFT
RAM pack (1M) (low power)	£49.16	£9.84	£59.00
RAM pack (1M) (CC)	£40.83	£8.17	£49.00
RAM pack (512K)	£37.50	£7.50	£45.00
RAM pack (128K)	£20.83	£4.17	£25.00
Cambridge Topper - Heavy Duty Version	NONE LEFT

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