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Old 7th Sep 2019, 1:08 am   #12
KesterLester
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Join Date: Aug 2018
Location: Cambridge, Cambridgeshire, UK.
Posts: 32
Default Re: Just some pics of my new (vintage) mobile

Quote:
Originally Posted by Techman View Post
I absolutely love it, pure genius!
I expect you already realise that there's a possible business opportunity making and offering the boards or converting actual phones to sell, should you want to.
That's a nice idea, but I don't think I have the time and skills to devote to something like that to make it pay for itself.

I would be happy to share for free the PCB design, etc, I created with anyone who wanted to use it for their personal use/fun, though, as I would hope they would have as much fun trying to debug it as I did. [The GMS connection SIM800L modules were the most finicky part. I broke about 8 or 9 before finding all the ways you should not mistreat them!]

If there really are people who think they were in a position to make this sort of thing turn a profit, and would want to take on the responsibility of negotiating with customers, then would be welcome to buy all my IP from me and do so. But I suspect anyone able to do that sort of thing would be the sort of person who could design a better (i.e. smaller and cheaper to manufacture) system anyway. So the person best placed to make a business of this is probably not me.

But I agree it would be super if someone could make a really cheap simple kit that made these things that could be bought as kits for £10 for people to make.

For those interested:

I think I was charged around 45 euro for the PCB -- though I think two PCBs would have been 60 euro and three would have been maybe 65 euro, or in that region, so I was paying through the nose as the order was so small. The Pyboard in the middle costs around £25-£35. Again, there are cheaper things you could use in its place, but I went for developmental simplicity rather than cost. The SIM800L module is around £5 a shot. You only need one but I think I bought ten in the end as a consequence of learning how not to kill it. I had to get a custom handset cable (£10 from someone on this forum) since I needed four wires not three, as i struggled to make the SIM800L cope with the inductive nature of the earpiece coil with a common ground to the microphone. That induction problem would have been solvable in better analogue circuitry on the board, but that's not my forte, so again, a compromise solution. The rest of the components are all relatively cheap. To to make just a second one to the same design (admittedly with no economies of scale) would therefore come to about £110 in components alone. It's not commercialisable in its current form, alas

Still, it was cheaper than an new IPhone, if you exclude the development time and opportunity costs!
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