Linn LM-1
The unit that ‘kicked’ it all off.
From the workbench
Restoration videos
LM-1 serial number 0038 is an early Rev 1 machine that had been badly neglected, and Part 1 asks whether it can be saved at all. Part 2 finds EPROM bit rot, where the data stored on the chips has degraded, and looks at whether AI can help recover it. Dead RAM was another casualty along the way. Part 3 carries the restoration on, and the final video gives the verdict: can it be saved? Oh yes!
Chapters 17
- Intro – a neglected LM-1
- Cleaning out the white residue
- Removing the leaking batteries
- First power-up: no +15V
- Tracing the short
- Failed bypass caps
- Recapping – but the CPU hangs
- First sounds!
- The hidden add-on board
- Removing the RAM chips
- Scoping the reset line
- More sounds come back
- Fixing the reset timing
- Arduino RAM tester
- New backup battery
- Faulty binary counters & IC tester
- Redrawing the schematic
Chapters 16
- Intro
- Backing up the EPROMs: bit rot!
- Copying the sound ROMs
- Tracing the board
- The faulty logic chip under the board
- Back together with new RAM
- First boot
- Swapping in a new EPROM B
- Write-safe mode
- The sequencer runs
- Hi-hats return & programming a beat
- Plan: rebuilding the EPROMs
- Using Claude AI on the bit rot
- Tip: raise VCC to read bit-rotten EPROMs
- Tip: piggyback chip trick
- Progress so far
Chapters 17
- Intro – the display works again!
- Toms and claps restored
- Original v1.1 EPROM images
- Joe Britt & the LUMA project
- Analysing the sound ROMs
- Deft Audio & new sound EPROMs
- Replacing the 393 counters
- Fixing tape sync (XR2211)
- Recapping the power supply
- Power supply test
- She boots
- Fitting Joe’s flash RAM board
- Booting on flash RAM
- Servicing the play/stop button
- Tracking down the memory wipe
- Fixing the back panel brackets
- Thanks & outro jam
More from the collection in the London College of Music playlist on the Really Nice Audio channel.