General Stuff(tm)

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JezC
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Re: General Stuff(tm)

Post by JezC »

I'd be tempted to get solar put in...but with a 100 year old slate roof & being in a conservation area I suspect there would be many complications...

Though the size of the roof (long side of the roof is south-facing as well) would give us room for many, many panels - though not quite as many as the install we've just had done at work.
I think they got over 90kWh yesterday, about half the typical consumption of the factory so we are now worrying that we might have to reduce the supply in the full summer sun (if we get any)...

Working on the comms with and control of the inverters is proving 'interesting' though...
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stephen_usher
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Location: Oxford, UK.

Re: General Stuff(tm)

Post by stephen_usher »

Yeah, slate roof is a problem... Planning in a conservation area even more so! No real "permitted development" in those areas.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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stephen_usher
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Re: General Stuff(tm)

Post by stephen_usher »

Today I have on the bench the Macintosh Portable, which became really unreliable during the mobile computing event last May.

After stripping it down I started probing around the sound circuit as the first symptoms of the problem would be garbled audio leading to a freeze. This is also where the largest amount of cap juice damage was and a large number of the vias are blackened.

IMG_4149.jpeg

When I started the system I was getting, after the bong, a high pitched tone which miraculously disappeared when I put the probe onto pin 40 of the sound chip. Looking at the schematic this turned out to be /SYS_RST the reset line. It was suspiciously showing as ~1.6V with what looked like some parasitic cross talk. Strangely, when the reset was held down it would go down to 0V though.

I decided to check the continuity on this pin, and I couldn't find it on any of the other chips which had /SYS_RST going to them... and the SWIM chip's reset pin was similarly isolated!

So, two bodge wires later and I'm soak testing with Crystal Quest.

IMG_4151.jpeg
IMG_4152.jpeg

So far there have been none of the sound issues and no crashes, but I'm not ticking the "fixed" box just yet.

I'll have to tidy up and glue down the bodge wires before I put it together, but it does look hopeful.
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Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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PhilC
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Re: General Stuff(tm)

Post by PhilC »

:cheer: :cheer: :cheer:

Glad to hear you've got it sorted as I remember it being a royal PITA the last time you had it apart.
If it ain't broke, test it to Destruction.
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stephen_usher
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Re: General Stuff(tm)

Post by stephen_usher »

No more instability! I declare it fixed!

Tidied up and hot glued the bodge wires and put the whole thing back together.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
Steve
Posts: 3307
Joined: 15 Sep 2017 11:49

Re: General Stuff(tm)

Post by Steve »

That's some real impressive troubleshooting!
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HigashiJun
Posts: 2383
Joined: 19 Jun 2020 07:21
Location: Tokyo

Re: General Stuff(tm)

Post by HigashiJun »

Well done !

:bravo:
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rubber_jonnie
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Joined: 17 Aug 2017 19:40
Location: Essex

Re: General Stuff(tm)

Post by rubber_jonnie »

Very nice to see it up and running again.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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stephen_usher
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Re: General Stuff(tm)

Post by stephen_usher »

No retro stuff today as it's been new car day.

First of all, to say good-bye to my old car...
IMG_0018.jpeg
When I first bought it...

IMG_4153.jpeg
And 15 years and one month later when I sold it.

So, it was off to to the dealer to pick up the new car, an electric vehicle which should have massively lower running costs though no-where near as well put together or thought out relative to the BMW, but it was far cheaper and 33% off list price. I had no choice of colour, so it had to be white.

IMG_4159.jpeg
IMG_4160.jpeg

Should have a range of around 200 miles in the Winter, more during the Summer, and once I manage to subscribe to the appropriate energy tariff it should be very cheap to charge. Strangely enough the insurance was actually £150 more expensive than the BMW 330d M Sport, and that was expensive! It's not as if it's at all sporty.
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Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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HigashiJun
Posts: 2383
Joined: 19 Jun 2020 07:21
Location: Tokyo

Re: General Stuff(tm)

Post by HigashiJun »

It's time to sell my Jag too...

Since our kids are now grown-up, something smaller would be enough for my wife and me.

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