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-   -   I found it! A very sorry looking MK14. (https://www.vintage-radio.net/forum/showthread.php?t=170727)

Buzby123 22nd Mar 2021 8:22 pm

Re: I found it! A very sorry looking MK14.
 
1 Attachment(s)
All my vias are filled with solder. Not sure if I did that, or it's how it was delivered.

I've been wondering why I had such a mix of IC sockets. Surely the kit must have supplied all the correct parts, not those horrible pin-strips like I had for the 8060 ?.

I'm continuing to check diagram against board, and re-checking all around IC16,17,18 which is where I did most of the track cuts. ( Remember, I had removed IC16 completely ! )

I won't be able to power up until I find some 'period style' 18 pin sockets, so tomorrow I'm going to try to resuscitate Micky's original bubble display. It will be a cool sight to see, Micky & Vicky side-by-side, both with their tiny LEDs shining !

SiriusHardware 22nd Mar 2021 8:25 pm

Re: I found it! A very sorry looking MK14.
 
There was actually an official branded / badged MK14 power supply, someone here, possibly Gertk64 (who has not been around for a while) had one. As we all built the machines ourselves we were a resourceful lot and generally already had something suitable, so I doubt whether many of the official ones were sold.

The 'real thing' was just the usual mains transformer / bridge / smoothing capacitor, nothing special, but I bet if one came up for sale it would go well up into the tens of pounds as long as it had its Science of Cambridge label present and intact.

SiriusHardware 22nd Mar 2021 8:27 pm

Re: I found it! A very sorry looking MK14.
 
Quote:

the kit must have supplied all the correct parts
Nope, the kit did not include sockets, at least not during the issue II period. To this day, all of the 18 pin ICs on my issue II are soldered in place because just like you now, I had problems finding 18 pin sockets and I was impatient to get the thing up and running.

ortek_service 22nd Mar 2021 8:52 pm

Re: I found it! A very sorry looking MK14.
 
Quote:

Originally Posted by SiriusHardware (Post 1356172)
There was actually an official branded / badged MK14 power supply, someone here, possibly Gertk64 (who has not been around for a while) had one. As we all built the machines ourselves we were a resourceful lot and generally already had something suitable, so I doubt whether many of the official ones were sold.

The 'real thing' was just the usual mains transformer / bridge / smoothing capacitor, nothing special, but I bet if one came up for sale it would go well up into the tens of pounds as long as it had its Science of Cambridge label present and intact.

They do give a 8V 600mA spec for it, in the add shown here: http://theoddys.com/acorn/Acorn%20Sy...4%20Advert.jpg
But unfortunately there's not a good view of a label, to make a replica.

The original PSU's for equipment often seem to get lost / thrown out - especially ones with moulded DC plugs when the wire gets bent too much and breaks, although this one must have had to be hard-wired. So can add to the rarity. Back then, I did gut a Commodore LED calculator one that always buzzed-loudly to reuse the case I've still got - which does look quite similar to the MK14 one.

Timbucus 22nd Mar 2021 9:38 pm

Re: I found it! A very sorry looking MK14.
 
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If you want to make a replica PSU you could probably adapt this photo which is what I plan to do when I find a suitable looking one.

Again snatched from an ebay sale in the days before I kept good records of sources so apologies to anyone who now owns it...

Timbucus 22nd Mar 2021 9:40 pm

Re: I found it! A very sorry looking MK14.
 
1 Attachment(s)
Not sure if this one helps as well but, it is an Issue IV naked on top...

Buzby123 22nd Mar 2021 10:06 pm

Re: I found it! A very sorry looking MK14.
 
Quote:

Originally Posted by SiriusHardware (Post 1356174)
Nope, the kit did not include sockets, at least not during the issue II period.

I can't remember the kit, or actually building the board. ( I've had a lot of sleeps since then ! ) Did it come in a box, or was it just a jiffy bag of bits ?.

SiriusHardware 22nd Mar 2021 10:09 pm

Re: I found it! A very sorry looking MK14.
 
I'm sorry to have to tell you that Tim can answer this question better than I can. Take it away, Tim...

Timbucus 22nd Mar 2021 10:14 pm

Re: I found it! A very sorry looking MK14.
 
Quote:

Originally Posted by SiriusHardware (Post 1356221)
I'm sorry to have to tell you that Tim can answer this question better than I can. Take it away, Tim...

Really - I expect you want photographs of it as well don't you...

http://oldcomp.cz/viewtopic.php?f=89...eb9a7&start=45

SiriusHardware 22nd Mar 2021 10:35 pm

Re: I found it! A very sorry looking MK14.
 
There you go.

Scroll down to the ~13th post on that forum page, and there you see an original unbuilt, boxed kit side by side with a modern replica of the kit. You can click on the image for improved bigness. Note the utter lack of sockets.

Timbucus 22nd Mar 2021 10:54 pm

Re: I found it! A very sorry looking MK14.
 
Also slightly higher up is the outer sleeve as well

ortek_service 23rd Mar 2021 12:47 am

Re: I found it! A very sorry looking MK14.
 
Also see here for a clearer one of what was supplied inside the box:

http://theoddys.com/acorn/Acorn%20Sy...MK14%20Kit.jpg

(I do recall seeing it on another website, that Chris got itoff - I think he may have got them to send him a higher res. one, and he may have credited this elsewhere)

Buzby123 23rd Mar 2021 1:08 am

Re: I found it! A very sorry looking MK14.
 
Quote:

Originally Posted by ortek_service (Post 1356266)
Also see here for a clearer one of what was supplied inside the box ...

That's not an issue 2 like mine. This one's got clicky buttons, not that rubber sheet I had to put up with.

I still can't picture what I received 40 odd years ago, but then I did have lots of other interests at the time. Remembering packaging was not as important as remembering girls phone numbers !.

SiriusHardware 23rd Mar 2021 9:57 am

Re: I found it! A very sorry looking MK14.
 
For the record, my issue II arrived in a very similar folded cardboard package. I still had that bit of antistatic foam that the ICs came in for years and years afterwards, maybe even still do.

Buzby123 23rd Mar 2021 11:11 am

Re: I found it! A very sorry looking MK14.
 
2 Attachment(s)
Todays project - Resuscitating an original MK14 display.

I found this while looking for something else.

Fairly sure this is Micky's original display. No idea why it's covered in Plasticine, maybe it was some temporary holding method, from the days before BluTac was invented.

I'm going to clean off the crap, clean the solder holes, fit a plug, and try it in Vicky.

Buzby123 23rd Mar 2021 12:16 pm

Re: I found it! A very sorry looking MK14.
 
1 Attachment(s)
It works !.

A couple of lifted tracks, they'd gone green under the gunk, so a bit of soldering both sides of the PCB fixed that.

Now I will be able to show Micky & Vicky running side-by-side !.

SiriusHardware 23rd Mar 2021 12:20 pm

Re: I found it! A very sorry looking MK14.
 
Still nice and bright after all this time! Probably doesn't have too many miles on the clock, that display.

ortek_service 23rd Mar 2021 12:25 pm

Re: I found it! A very sorry looking MK14.
 
Quote:

Originally Posted by Buzby123 (Post 1356269)
Quote:

Originally Posted by ortek_service (Post 1356266)
Also see here for a clearer one of what was supplied inside the box ...

That's not an issue 2 like mine. This one's got clicky buttons, not that rubber sheet I had to put up with.

Well it does hopefully show that IC sockets weren't included - in that version at least. I would have expected sockets to have been in there in the early version at least, being as SoC adverts all show all of the IC's socketed (So a bit misleading if they never included these, and you had to buy your own), and maybe then removed these for cost-cutting.
I suppose they could have added them later on, as even ready-built ZX81's & Spectrum's often had many of the more expensive IC's socketed, but was a bit variable over the years as to which ones had sockets (Luckily, always the ULA at least).

SiriusHardware 23rd Mar 2021 4:39 pm

Re: I found it! A very sorry looking MK14.
 
I'm certain sockets were never supplied with MK14 kits as the instructions state that it's advisable to fit sockets, which would be a strange thing to say if sockets were actually included. If they gave you them, then of course you would fit them.

They also advised the use of a heatsink on the regulator, and they didn't supply one of those either...

TonyDuell 23rd Mar 2021 4:59 pm

Re: I found it! A very sorry looking MK14.
 
I seem to remember that either SoC or one of the hobbyist suppliers (probably the former) sold a pack of the right sockets for the MK14 board. I know I got it when I built my MK14. The large electrolytic capacitor was 'optional', it was not included in the kit and I never fitted it as the machine worked on my homebrew power supply without it.

I also remember a note about the using the correct 16 holes in those 18 pin locations. Maybe a slip of paper tucked in the manual. I doubt I could find it now though.


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