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

Buzby123 31st Mar 2021 8:06 pm

Re: I found it! A very sorry looking MK14.
 
1 segment in 1 cell.

If it was the same seg in every cell I would suspect the drive circuits, but if I set '8888' and get '8G88' then I know the display is broken, especially as I can swap with another identical display, and that shows '8888'

SiriusHardware 31st Mar 2021 8:13 pm

Re: I found it! A very sorry looking MK14.
 
As you no doubt guessed, I was hoping it was the same segment in all cells. I forgot you had another display to try.

SiriusHardware 8th May 2021 8:27 am

Re: I found it! A very sorry looking MK14.
 
Buz, did you ever get around to replacing the displays on Micky?

Buzby123 8th May 2021 9:18 am

Re: I found it! A very sorry looking MK14.
 
Yes, I'm still here !.

The display board was quite badly corroded, the pins had rusted through on every FND507. I stripped it down to a bare board, cleaned it, then fitted sockets for the new FNDs.

It now works as before, i.e. a bit dim, but I'm happy with it at the moment. Just need to fit it back into Micky's case.

The problem I'm working on now is the keyboard. I've got a nasty feeling that the switches are duff.

I'm still not able to put as much time into this as I'd like to, but Micky will eventually be working again, it's just taking a lot longer than I expected !.

Cheers,

Buzby

SiriusHardware 8th May 2021 9:37 am

Re: I found it! A very sorry looking MK14.
 
Those low-profile C&K switches (and the switch caps) were still available at Digikey last time I checked, exact links have been posted before in these threads but I can dig them up again if needed.

My replacement keypad also uses those same switches and mine are still working but mine has always been stored in a slightly less hostile environment.

Buzby123 5th Jun 2021 2:06 pm

Re: I found it! A very sorry looking MK14.
 
1 Attachment(s)
I've still not had time to work any more on Micky, but while looking for something else, I found this ...

Timbucus 5th Jun 2021 2:41 pm

Re: I found it! A very sorry looking MK14.
 
Cool - you replied to an ETI advert then?

Buzby123 5th Jun 2021 2:44 pm

Re: I found it! A very sorry looking MK14.
 
1 Attachment(s)
Not sure what advert it was, but ETI is a strong possibility.

Just found the receipt for the extra RAM, IO, and cassette interface.

( Different address, 'cos it was posted to my workplace. )

Timbucus 5th Jun 2021 2:55 pm

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

Originally Posted by Buzby123 (Post 1380569)
Not sure what advert it was, but ETI is a strong possibility.

Just found the receipt for the extra RAM, IO, and cassette interface.

( Different address, 'cos it was posted to my workplace. )

Thanks for sharing that as well - they are fascinating - esp as it was not Science of Cambridge they had already switched to Sinclair.

I was going by the end of the Item description "...ETI7" which was the sort of thing that was done then to identify which magazine advert had worked. This one does not seem to have it recorded of course.. probably as you bought direct as an existing customer.

SiriusHardware 5th Jun 2021 7:31 pm

Re: I found it! A very sorry looking MK14.
 
Advertisers would often have you add the false extra address line 'Dept PE', the purpose of which was to tell the advertiser where it was that you had seen their ad - Practical Electronics in this example.

Buzby123 5th Jun 2021 9:33 pm

Re: I found it! A very sorry looking MK14.
 
ETI7 - does the 7 mean July ?.

There was an MK14 advert in the July 1978 ETI, see here https://worldradiohistory.com/UK/Ele...1978-07-78.pdf

So it looks like that was the advert I replied to, and then bought the extra bits a few weeks later. Total cost for expanded MK14 plus cassette interface was 70.87 !

That issue of ETI has loads of good stuff. On page 11, as well as yet another SC/MP system, there is an article about fake chips, and another about rip-off copies.

SiriusHardware 6th Jun 2021 9:02 am

Re: I found it! A very sorry looking MK14.
 
The ad (right near the end of the issue) took some finding, mainly because the rest of the issue was so interesting - but when I found it I did notice that the 'fill in, cut out and send' order slip had 'ETI7' printed in the lower right corner, so that seems conclusive.

Also in that issue, an article by John Miller Kirkpatrick of SCRUMPI fame.

SiriusHardware 6th Jun 2021 9:27 am

Re: I found it! A very sorry looking MK14.
 
I have to say that all of this material (letters, receipts, manuals and other paperwork) which you seem to have retained adds up to an excellent provenance for the machine, so if you (or your descendants) ever eventually decide to sell Micky it would add considerably to the overall value provided it is all carefully kept together.

Maybe print out that page from ETI and add it to the document stash, as a way of saying 'this is how and when the machine was originally ordered'. It's a pity you don't still have that original ETI issue with a hole where the order slip should be. ;)

Timbucus 6th Jun 2021 10:28 am

Re: I found it! A very sorry looking MK14.
 
Sirius is correct, keeping the originals and reference material is an important part of the provenance and history. I actually have that issue (no missing return slip though!) and the IES machine is in my SCMP notes with its use of 5 bubble displays - one per register...

They also mention a range of expansion cards in either LCDS ro ETI 31 way connectors...

Also on page 36 is the source of the Mullard Amp modules I based my home made stereo on https://twitter.com/timbucus/status/1258778407489413122

SiriusHardware 6th Jun 2021 11:13 am

Re: I found it! A very sorry looking MK14.
 
Briefly OT- I still have my version of that amplifier made with the set of three Mullard modules (2 mono PA and one stereo preamp)- it was also my first ever stereo amp, used in conjunction with the guts (only) from a Ferrograph tuner which a friend had ...borrowed from the factory where he then worked. I had the whole thing working just in time for the Hitch-Hiker's Guide To The Galaxy, which was one of the most overtly stereo programmes ever broadcast.

Timbucus 6th Jun 2021 2:08 pm

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

Originally Posted by SiriusHardware (Post 1380785)
Briefly OT- I still have my version of that amplifier made with the set of three Mullard modules (2 mono PA and one stereo preamp)- it was also my first ever stereo amp, used in conjunction with the guts (only) from a Ferrograph tuner which a friend had ...borrowed from the factory where he then worked. I had the whole thing working just in time for the Hitch-Hiker's Guide To The Galaxy, which was one of the most overtly stereo programmes ever broadcast.

Good grief - that was one of the first series I taped as well - I assume I used an external tuner we had from somewhere as my system only had a turntable and cassette unit - all built into a hollowed out bedside unit from MFI... Lent the set of cassettes to a girl in school in my home made ring binder... my loans book mentions chasing for a return.

We now return from our interval to normal Mickey services...

Buzby123 3rd Sep 2021 7:44 am

Re: I found it! A very sorry looking MK14.
 
Hi All,

It's been exactly a year since Micky came down from the attic, looking very sad.

In that year I've got Micky's MK14 working, and a Vicky as well ( although that was not easy. )

I had to give up trying to get the daughter board working, so Micky is now back to a standard Issue II.

I've still got the keyboard left to do, and some of the LED/Switch circuits are still erratic.

This last year has been difficult for me, not just Covid, there's been lots of other medical stuff as well. I could not have done this work without the encouragement and advice from the forum, so thanks to all who have helped.

Cheers,

Buzby

SiriusHardware 3rd Sep 2021 8:05 am

Re: I found it! A very sorry looking MK14.
 
I think this forum - and not just this little corner of it - has been a great haven and source of comfort and companionship to many of us during recent troubled times.

If you've taken Mickey all the way back down to plain issue II, does that mean you've also removed the memory hole mod for 0200-07FF, or did you leave that mod in?

Buzby123 3rd Sep 2021 8:49 am

Re: I found it! A very sorry looking MK14.
 
Yes, the hole is gone. It's back to multiple copies again.

I'm not bothered about this. Micky is never going to have to take part in any experiments again, except maybe the addition of a downloader.

SiriusHardware 3rd Sep 2021 9:12 am

Re: I found it! A very sorry looking MK14.
 
I do believe Slothie has some of his uploader opto interface PCBs left, a PM to him and a self-addressed jiffy bag will probably secure one. They aren't too hard to put together anyway but Slothie's PCB makes it almost too easy.


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