Just some pics of my new (vintage) mobile
 

You might recognise the original frame, bells and solenoid of a GPO 332 (and spot a few wired heading off to the original dial), but the motherboard, LiPo batter and the rest of the electronics are/were all my work in February.

To text, I dial without lifting the receiver, and after a confirmatory "ding", then use the letters on the dial. For example: to get an A in a text you dial a 2. To get a B you dial the 2 but with the "call exchange" button depressed at the beginning of the dialling action. To get a C you dial a 2 but with the call exchange button depressed at the end of the dialling action. And to get a "2" in a text, you keep the call exchange button depressed throughout the dial action. Thus it is one dial action per letter, which is reasonable. To phone you lift and dial as you would as normal.

Re: Just some pics of my new (vintage) mobile
 

That is absolute genius!

Regards,
Paul

Re: Just some pics of my new (vintage) mobile
 

Clever stuff. Is this actually a mobile, IE, you could sit in a pub or on street corner and make a call? I had an GPO phone a while back and used it briefly, but someone had reprogrammed my head since I last used one and using the dial was a pain. I now have issues with texting, it's too slow, and takes ages what with all the miskeying and I can't keep up with my daughter who can fire off 5 texts to my one on her Iphone.

However, I'd love your phone if only to leave it on a street corner, sit across the road and ring it occasionally to see if anyone picks up. Mind you, someone's bound to pinch it.

Andy.

Re: Just some pics of my new (vintage) mobile
 

Yes, it is a proper mobile, with a pay as you go sim, so it which works out and about. On account of its weight I don't carry it round much, though. I have been rung in the pub with it, where it caused a few heads to turn, mostly on account of the friendly sounding ring, I think, which just makes people smile. But, indeed, text speed is nowhere near what you can do on the kids phones. I have not yet tried it at speed (e.g. "on the train") which is something I must try eventually, to see how well it can hop between masts.

Re: Just some pics of my new (vintage) mobile
 

I absolutely love it, pure genius!

I have several of these phones, but unfortunately none of mine have the "call exchange" button.

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.

Re: Just some pics of my new (vintage) mobile
 

That's certainly one up on having landline telephone(s) connected to a Fixed Wireless Terminal, especially with the ability to send texts as well. Presumably there's no way to receive texts on it.

Assuming the letter assignments as per mobile 'phones, how do you access the fourth letter on 7 (S) and 9 (Z) and a space between words?

Re: Just some pics of my new (vintage) mobile
 

Regarding receiving of texts -- the plan is that when a text comes in, the text will be internally converted to morse code, and then played out through the bells. It's only a 30min job to implement that -- but my wife won't let me do that until I finish the kitchen fume extractor. So this 30 min final tweak is my incentive to get that done. At the moment, the only thing that happens when you send it a text is that the bells "tinkle".

The GPO 332 dial has onlythree letters (P,R,S) on the "7" since the Q (and the O) is on the "0". So no no extra functionality is needed for S. One thing it can't do, however, is "Z". It *could* do Z if I wanted it to (e.g. I could add it as an extra letter available by "0") however since these old dials didn't have a Z, I decided to adopt that as a design "feature".

Inter word spaces are indicated by "1" (since the 1 key has no letters on it), and a double space "11" indicates end-of-message. I can't send punctuation.

Re: Just some pics of my new (vintage) mobile
 

That even beats my "746 plugged into an Asterisk box with a GSM card"! :clap: I love it!

Re: Just some pics of my new (vintage) mobile
 

Perhaps this picture shows the number-to-letter assignments on the dial more clearly than my original post. [See discussion in my last reply.]

Re: Just some pics of my new (vintage) mobile
 

If she's allowing it at all, I wonder whether she appreciates the implication of receiving bursts of long and short rings of the bells. ;D

That seems appropriate to use the letter assignments as per the old dials. The absence of "Z" shouldn't be too much of a hardship, even if it may occasionally require a little "creative spelling".

Sounds good.

As previously mentioned, it has possibilities for sales - at least within the vintage community - if it can be produced at not too exhorbitant a cost.

Re: Just some pics of my new (vintage) mobile
 

On the issue of inbound SMS; texts to geographic phone numbers are generally, by default, presented as text-to-speech.
And,
giving your contacts a VoIP 01223 number to dial that is forwarded to the 07 SIM will, I would suggest, enhance the project.

I use my Raspberry Pi Asterisk server to do the forwarding, but you could use a free service "in the cloud":
http://pbxes.com

You can get your SIP trunk with a Cambridge number from:
https://www.sipgatebasic.co.uk/

You could apply credit to the Sipgate account and use it to make the second leg of the call to the mobile, but there are much cheaper alternatives we can discuss.

I'd be more than happy to help configuring this with you.

Re: Just some pics of my new (vintage) mobile
 

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!

Re: Just some pics of my new (vintage) mobile
 

Thank you for the offer!

I don't know what it is with me, but I seem to get a mental block every time I try to understand things like Asterisk and how PBX systems work. I've tried to understand them a few times, but each time I get lost. This is despite being a person who gets his home phone service comes from a commercial voip provider https://www.voipfone.co.uk. Though I am happy that my [admittedly very small] monthly payments to voipfone support a small business (especially given that their service works and I don't have to think about system maintenance, etc) I've always had a nagging suspicion that if only I properly understood how incoming and outgoing connections to the trunk network are made from IP based systems, then I'd end up enjoying a phone system that suited my exact needs, rather than one which only approximately does so.

I agree that a text-to-speech SMS reception system would be more practical for anyone who wanted this system as a primary means of communication.

I think I will see if I can get the morse version working first, though, as it could be more "unusual". I suppose I could arrange some kind of ring-back-by-voice system, though, since (though I have not used it yet) I believe the SIM800L chip I am using has access to the internet over GPRS. E.g., if calls were routed to this mobile via a RPi-based PBX system of some kind, then if the mobile gets a text I mis-hear, or don't want to hear by morse, then I could in principle dial a special "code" from the mobile that would send a GPRS message to the RPi that would instruct it to re-send the last SMS back as a text-to-speech sound message.

Hmm. Yes, I agree there are lots of interesting possibilities in the directions you mention.

But I must finish the kitchen first or will get it trouble ...

Re: Just some pics of my new (vintage) mobile
 

Many a true word....

Bryan

Re: Just some pics of my new (vintage) mobile
 

Was this the one displayed in Belgium?

Re: Just some pics of my new (vintage) mobile
 

Ha ha! :D

Re: Just some pics of my new (vintage) mobile
 

"Many a true word...." Brilliant : )

Andy.