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DoG's Hx Mongrel build attempt

Posted: 12 Oct 2019 12:12
by DoG
Got myself a donor Atari STfm. A C070859 Rev 2.1. Tested it and it worked fine, so I know that the components are not faulty. Lucky for me it was super clean inside...
Filthy Atari.jpg
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Keyboard right side.jpg
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Keyboard left side.jpg
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Apparently someone has fixed it at some point.
Service.jpg
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Planning on changing the rubber domes for some stiffer ones. ""TT touch" feeling. We will se about that.
Keyboard dirty.jpg
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Keyboard and parts clean.jpg
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Let's start desoldering then...
Board with stuff.jpg
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Board with less stuff.jpg
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Components.jpg
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I removed the three oscillators as well as the PSU attachment pins.


Washed the shell with soapy water.
Cleaned shell.jpg
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I haven't ordered any components yet. But I do have a 4Mb 72pin RAM module, some sockets and a 25 pin female and male connector already.

Re: DoG's Hx Mongrel build attemt

Posted: 12 Oct 2019 12:35
by PhilC
Good work so far :dualthumbup:

Re: DoG's Hx Mongrel build attemt

Posted: 05 Nov 2019 16:32
by DoG
Ordered all the stuff I was missing yesterday. Seems the postman/woman is coming with it tomorrow. Lucky I already got a few DS1315 and the crystal for it, coz that sucker is expensive. At least from digikey. Well, I guess not that expensive.

Re: DoG's Hx Mongrel build attemt

Posted: 05 Nov 2019 16:40
by exxos
I have found a cheaper source of DS1315 (not china crap either!) , not massive cheaper, but I would have to buy 100 of them :(

Re: DoG's Hx Mongrel build attemt

Posted: 05 Nov 2019 16:56
by stephen_usher
The TT keyboard isn't stiffer, it's FAR lighter touch, more similar to current keyboards. Not surprising as it's made by Mitsumi who made/make cheap PC keyboards for a living.

Re: DoG's Hx Mongrel build attemt

Posted: 26 Nov 2019 17:54
by DoG
stephen_usher wrote: 05 Nov 2019 16:56 The TT keyboard isn't stiffer, it's FAR lighter touch, more similar to current keyboards. Not surprising as it's made by Mitsumi who made/make cheap PC keyboards for a living.
Ok, so wrong word to explain it. More "tactile" then. Either way, I have fitted those pink rubber domes and screwed it together now. Started to fit 'RETURN' and 'SPACE' bar because those are the most fiddly to deal with. But seems that I have lost 'E' and 'X' during the cleaning process. Unbelievable!! How did that happened? Well, got some "new" keys on the way.

DoG keyboard.png
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The package with mongrel board arrived today but I don't think I have time to solder that much before Christmas. Great project during the holidays.

BTW, I feel rude but were we suppose to get an opto coupler in the package? I didn't get mine if that was the case. Never mind, I just ordered some of those elsewhere. Got the DAC in small plastic jar. Neat package.

Re: DoG's Hx Mongrel build attempt

Posted: 26 Nov 2019 18:10
by exxos
I never sent any optos out, only the DAC's. With so many boxes of junk everywhere I just never found them.

Re: DoG's Hx Mongrel build attempt

Posted: 26 Nov 2019 18:36
by DoG
exxos wrote: 26 Nov 2019 18:10 I never sent any optos out, only the DAC's. With so many boxes of junk everywhere I just never found them.
Aah. No worries!

Re: DoG's Hx Mongrel build attemt

Posted: 26 Nov 2019 18:38
by derkom
DoG wrote: 26 Nov 2019 17:54 Got the DAC in small plastic jar. Neat package.
It took me a moment to figure it out, but when I saw the underside I realised it's a contact lens box. Good choice, @exxos ! :geek:

Re: DoG's Hx Mongrel build attemt

Posted: 26 Nov 2019 18:44
by exxos
derkom wrote: 26 Nov 2019 18:38 It took me a moment to figure it out, but when I saw the underside I realised it's a contact lens box. Good choice, @exxos ! :geek:
I think they were "make up" tubs.. but yeah, solid enough to ship the chips in, couldn't really think of any other simple way of doing it :)