General Stuff(tm)

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stephen_usher
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Re: General Stuff(tm)

Post by stephen_usher »

Thanks!
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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rubber_jonnie
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Re: General Stuff(tm)

Post by rubber_jonnie »

stephen_usher wrote: 03 May 2023 17:38 Something slightly retro worked upon this afternoon, but not computing.

I've been working on my Dad's car getting it presentable for the funeral tomorrow.

I do hope everything goes well tomorrow as well, having been through my own Dad's funeral in November, so I can fully appreciate what you're dealing with.

The car thing is a funny one, we sold my Dad's car on, but when they came to collect it, the damn thing started, albeit from a booster battery, and drove onto the low loader. I'd never expected that after sitting for 7 years in the garage.

I hope you can use it with pride tomorrow, especially with the connected ownership of you both.

Take care.
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 »

Having "fun" with a Mac SE/30 today...

I bought four new 4MB SIMMs from eBay for the machine but they don't work, sort of.
  • Put all four SIMMs into bank A: fails POST, corrupt screen.
  • Put all four SIMMs into bank B and known good in bank A: fails POST, corrupt screen.
  • Replace one of the known good 1MB SIMMs with one of the new SIMMs: System boots.
  • Replace more than one known good 1MB SIMM with any of the new ones: fails POST, corrupt screen.
Test 3 suggests that the lower 1MB at least of all four SIMMs is working correctly.

I'm puzzled, especially as the machine fails to POST with the new RAM in the upper bank and so shouldn't be used for the display etc.
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 »

Decided to check A10 (pin 19) on the SIMMs so fitted them into bank B. Put the scope probe on pin 19 of the nearest SIMM, switched on... The machine booted... and continues to boot fine.

It's having a laugh.
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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rubber_jonnie
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Re: General Stuff(tm)

Post by rubber_jonnie »

stephen_usher wrote: 07 May 2023 15:53 Decided to check A10 (pin 19) on the SIMMs so fitted them into bank B. Put the scope probe on pin 19 of the nearest SIMM, switched on... The machine booted... and continues to boot fine.

It's having a laugh.
Oh, how odd. Having been through RAM issues with my Classic that traced back to a single bad resistor, the weirdness you're having seems about normal!!
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 »

I reflowed the solder on the SIMMs' pads. I think it was a connection issue with the PCBs being slightly thinner than the originals.

Works reliably now.
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.
User avatar
stephen_usher
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Posts: 7376
Joined: 13 Nov 2017 19:19
Location: Oxford, UK.

Re: General Stuff(tm)

Post by stephen_usher »

Top tip: Don't try to use flammable freeze spray to try to stop the sticky bumper on an old Conner hard drive from being sticky...

I just tried to revive the original Falcon IDE drive so that I could attempt to image it from a Linux box. Sprayed the freeze spray under the lowest platter, where the bumper hides after moving the heads out of the way and now the platter won't spin properly and it's still sticking the heads.

Oh well. The drive was toast anyway.
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 »

@stephen_usher will a bath in IPA help the old drive?

At least it didn’t catch fire :lol:
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 »

Disk flambé. Lovely!
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.
User avatar
rubber_jonnie
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Posts: 14888
Joined: 17 Aug 2017 19:40
Location: Essex

Re: General Stuff(tm)

Post by rubber_jonnie »

Nobody wants sticky bumpers...
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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