Sinclair ZX80 / ZX81 / Z88 Forums

Of the eBay bought 8 bit machines (not just ZX81's) that I have obtained I have noticed the following as common problems: Keyboard problems - membrane broken or non-functional keys :( , Tarnished connectors (e.g. expansion edge connector) - cleaning normally fixes this :D , Intermittent faults with ...

One thing I learned about computers way back when, is to always have at least one back-up copy... Of course despite knowing this, I still sometimes end up losing items that are a work in progress :cry: (a lot of the time as I am thinking, I'll just make this change then save a copy, then crash :o :s...

PokeMon wrote:Because I can produce in a smaller series I can offer a 3-package.
Maybe I can offer a 5-package as well for about 16 GBP.
But to do I want to collect some orders first.

One pack of five please. Please consider this a firm order.
Mark

Now I ordered only Prototype version with 5 pieces, resulting price will be GBP 7,00 plus GBP 2,00 postage for an envelope. FIFO order service - first in, first out. Should be delivered this month as promised. Now I found a producer in China for smaller series and I could do a smaller series which ...

Selling like hotcakes...
Three ZXpands sold today
Mark

Great pictures Andy
It looks so much better in its home environment next to a Z80 on a Zeddy PCB
Mark

Some transistor information TO-92 BC547, BC548, BC549 pinout.jpg Pinout for 2N3904 here: http://www.reprise.com/host/circuits/transistor_pinouts.asp Notice that the pinouts are not the same, but both will fit in the same holes on a circuit board 8-) Other transistor pinouts: http://hamradio.lakki.ik...

Possible transistors include

BC547B, BC547C
BC548B, BC548C
BC549B, BC549C

2N3904 should also be okay ( a very common transistor) and even available from http://www.radioshack.com (as well as many other suppliers)

http://www.digikey.com stock a good range

Mark

I understand the problem, the only thing I can suggest, is the boards being sold in packs of 5 or packs of 10. If they are put on http://www.sellmyretro.com/ by Rich that will go a long way to helping with the problem. Myself, I would be interested in buying 5, but am not sure I would find a use for...

Bill, whereabouts in the world are you? There are many silicon transistors (which are used as both signal amplifiers and digital electronic switches) that will do the job. NPN is a type of transistor (but not a part number), transistors are available in a number of different types. Why do I need to ...