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Old 31st Mar 2019, 2:49 pm   #148
Timbucus
Tetrode
 
Join Date: Mar 2019
Location: Barry, Vale of Glamorgan, Wales, UK.
Posts: 77
Default Re: MK14 schematic revisions

I can certainly vouch that the cost and difficulty of sourcing parts for a replica is rising, glad I am doing it now.

Just like to say thanks to all of you for the amazing amount of discussion on here around this little device. I am in the process, with the various signposted resources in the threads, of building at least one (as often I order two of something when the postage is the significant bit) based on a JM (Issue 0) board I bought, little did I realise how much time and money completing it would cost... and how much a mistake on the first key order would add, when the needed ones are no longer produced and therefore even more expensive - they are Multimec 3FTL6 or H9 as that is not documented elsewhere - they are hidden until the red keycap and the reproduction keypad housing.

I have not yet heard back from Martin on getting some pre-programmed PROMS but, I have included 2 on my order along with the 8060 and 8154 - if they turn out to be original (and blank...) DM then I would obviously need to find someone who can program them for me. Even better a pair of the Tesla ones which I have, although I read in other threads are proving difficult to find / create a programmer for...

I attach a photograph of the board so far - there appear to be no shorts between any data or address lines etc and 5v/Gnd is correct on the sockets but, I can do little more until my CPU, RAM and programmed PROM's arrive. The connector at the top was a way to connect power and to build the Single step circuit / have dupont access to the I/O connections. I also have the parts on order to make the clever keyboard / PI programmer from SiriusHardware as I am sure I will get tired of the hex data entry...

The display is a modern one which I gave into as I did not have the heart to rip apart the Text880 I bought, as it still actually works...
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