Progress blog on CosmicPuppets STFM servicing
Progress blog on CosmicPuppets STFM servicing
Hey guys,
Just a progress blog that I'll update as I go:
Motherboard: C070523-001
Problems:
* Corruption on DMA transfers, Ultrasatan
* Video output issues with sync/banding
Required services:
1. New Exxos PSU
2. STFM Video capacitor replacements (exxos kit)
3. Remove old motherboard ram
4. Complete motherboard re-cap
5. DMA and floppy resistor pull-up fixes
Just a progress blog that I'll update as I go:
Motherboard: C070523-001
Problems:
* Corruption on DMA transfers, Ultrasatan
* Video output issues with sync/banding
Required services:
1. New Exxos PSU
2. STFM Video capacitor replacements (exxos kit)
3. Remove old motherboard ram
4. Complete motherboard re-cap
5. DMA and floppy resistor pull-up fixes
Repairs & Servicing for Atari & Amiga machines (and any other retro computers) Located in the West Midlands UK. PM me if you require assistance.
www.solidstatesociety.co.uk
www.solidstatesociety.co.uk
Re: Progress blog on CosmicPuppets STFM servicing
Just finished soldering in Exxos new PSU
PSU in the machine
Test the machine boots with the new PSU
Time to recap the video circuitry
All caps replaced and resistor added for sync
Repairs & Servicing for Atari & Amiga machines (and any other retro computers) Located in the West Midlands UK. PM me if you require assistance.
www.solidstatesociety.co.uk
www.solidstatesociety.co.uk
- Cosmic Puppet
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Re: Progress blog on CosmicPuppets STFM servicing

US Atari 520 STFM (C070523-001 REV.D1) 4MB Marpet Upgrade, TOS 1.04, EmuTOS 1.0, Ultrasatan, PP Driver, Original Floppy Disk Drive, NEC Multisync EA193Mi Monitor.
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Re: Progress blog on CosmicPuppets STFM servicing


https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
https://www.exxoshost.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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Re: Progress blog on CosmicPuppets STFM servicing
@Steve Nice work sir.
Collector of old Atari things:
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2
Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk
800XL + Ultimate 1MB, 2x 1010 cassette, 1050 + Happy mod, 65XE (128k +APE Warp) & XC12, SIO2SD, 2600jr, 7800 and Lynx II
Atari 520ST (1Meg), 1040STF long button floppy, 2x 1040 STFMs + Gotek, 2x 4160STE with 32Mhz booster, ROM switcher, Mega ST1, Mega ST4, not to mention various bare ST boards for testing including a PAK 68/2

Plus the rest..
Amiga stuff, Mac stuff, Sinclair stuff etc...
www.electronicnothingness.co.uk
Re: Progress blog on CosmicPuppets STFM servicing
Bye bye DRAM 

Repairs & Servicing for Atari & Amiga machines (and any other retro computers) Located in the West Midlands UK. PM me if you require assistance.
www.solidstatesociety.co.uk
www.solidstatesociety.co.uk
- Cosmic Puppet
- Trusted Guru
- Posts: 885
- Joined: Fri Aug 02, 2019 1:03 am
- Location: West Yorkshire
- YouTube: https://www.youtube.com/channel/UCbuSMn ... MoHknHryLg
- Contact:
Re: Progress blog on CosmicPuppets STFM servicing
That's awesome!
US Atari 520 STFM (C070523-001 REV.D1) 4MB Marpet Upgrade, TOS 1.04, EmuTOS 1.0, Ultrasatan, PP Driver, Original Floppy Disk Drive, NEC Multisync EA193Mi Monitor.
Re: Progress blog on CosmicPuppets STFM servicing
Remove the cap inside the modulator he says... Steve says no problems...
Holy mother of lord Okay, job done lol
Motherboard fully re-capped with Vishay, Panasonic and Nichicon caps.
Holy mother of lord Okay, job done lol
Motherboard fully re-capped with Vishay, Panasonic and Nichicon caps.
Repairs & Servicing for Atari & Amiga machines (and any other retro computers) Located in the West Midlands UK. PM me if you require assistance.
www.solidstatesociety.co.uk
www.solidstatesociety.co.uk
Re: Progress blog on CosmicPuppets STFM servicing
Looks like a nice job there @Steve
If it ain't broke, test it to Destruction.
Re: Progress blog on CosmicPuppets STFM servicing
Floppy drive resistor fix applied:
Test floppy and system by loading frontier:
Repairs & Servicing for Atari & Amiga machines (and any other retro computers) Located in the West Midlands UK. PM me if you require assistance.
www.solidstatesociety.co.uk
www.solidstatesociety.co.uk