ZX81 extender board for development

[PokeMon]

Hi there,

as a question to all hardware developpers for ZX81 or people who wnat to get to.
I never found an extender board which can be used for own hardware and asked some people in the german forum - told me that's not existing or never heard from.
So I developed this kind of board which gives the bus through other hardware (which can be connected to own developed hardware).
So original Sinclair products like memory extension, printer and so on (even ZXpand for example) can be connected together easily with own (new) developed hardware.
The concept is to put a card with standard 2-row connectors (female on extender board, male with 90 degree on development board) on it.
As you can see it has 3 rows for use of VG64 connectors for ZX96 (A-C rows) which is used by some german guys.

Here is a sample board to guess what I mean. I have no real picture because not produced yet.
It's meant like a PCI card you put vertical into a PC mainboard with connectors like this.

sample.jpg (40.46 KiB) Viewed 6553 times

Component side view (M 2:1)

zx81ext_compside.png (6.43 KiB) Viewed 6552 times

Soldering side view (M 2:1)

zx81ext_soldside.png (7.27 KiB) Viewed 6551 times

Due to setup cost I have to order 150 boards. It size is 2.35 inch x 1.2 inch.
I plan to sell in portions of minimum 10 pieces for 20 GBP (2 GBP / board).
If I can sell mostly all boards price can be a bit downed but I think its hard to find 15 people.
I now have 3 people from germany, if I can get two or three more people I will order, could be delivered in about 2 weeks.

So what do you think ?

Kind Regards,

Karl

[sirmorris]

I'd like a couple of these but 10 may be too many. It does seem like the kind of thing that Rich might sell though - Rich? Fancy a few for SMR?? I'd buy 2 or 3...

[RWAP]

Yes I would be interested in stocking some of these - we then need a standard eurocard type board to plug into it for development

[PokeMon]

I'd like a couple of these but 10 may be too many. It does seem like the kind of thing that Rich might sell though - Rich? Fancy a few for SMR?? I'd buy 2 or 3...

Yes I know it's maybe many for one person but if I produce same as prototype board I will have only a few with a price of about 10 GBP per piece.
If I produce a series by one pcb factory in germany, minimum ordering value would be about GBP 200 including setup costs or as alternative a protoype service for about 50 GBP per bigger board which you could cut off 5 pieces.

So I thought about sell them in 10 piece packages but I am sure not to sell all packages.
Maybe I hold them long time, maybe forever.
So I planned to sell them in a fair package price of 10 boards for 20 GBP.

Maybe if some more people need, you could do a combined order and split yourself. This would be more easy.
I don't checked all manufacturers in GB (only 2), but I think there have comparable prices.
If I could sell 5 packages of these boards I have about half of cost of production.
That's why I am ask this way for interest.

[1024MAK]

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 10. Of course, a lot does depend on the final price

One other thing. They may sell better if they were sold with edge connectors.

Mark

[Andy Rea]

i'd have a 2 or 3, better with the edge connector but i'll settle witout if there is no other option.

Andy

[PokeMon]

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 would result in following prices:

"3-pack" GBP 10,00 plus postage

Maybe this is more interesting for developers.
Series boards could be delivered in january 2012 if somebody interested.
Somebody means I would order if I have about 5 people / orders for the series boards.

Price is only for board without connectors.

PS: I made a small change in layout, board is now 2.35 inch x 1.15 inch

zx81extm_compside.png (5.18 KiB) Viewed 6399 times

zx81extm_soldside.png (5.76 KiB) Viewed 6399 times

[1024MAK]

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 would result in following prices:
"3-pack" GBP 10,00 plus postage
Maybe this is more interesting for developers.
Series boards could be delivered in january 2012 if somebody interested.
Somebody means I would order if I have about 5 people / orders for the series boards.
Price is only for board without connectors.

Now you got me all fuzzed
As I said above, I would like five boards, but I am happy to wait a little while for the "series boards" (I presume you mean normal production run boards as opposed to prototype boards). So would you supply five boards, or would you sell in multiples of three boards?
Mark

[PokeMon]

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.

[sirmorris]

I'll take a 3 pack. Consider that a firm order

C