About untergeek

Early digital immigrant. Father. Maker. Tinkerer. Serendipist. Journalist. Synth nerd.

Repairing your Macbook Air M1 (2020) if the trackpad does not click

Suddenly, the Mac did no longer click with me: The trackpad in my MacBook Air M1 (end-2020) no longer clicked, seemed to have jammed, gave no haptic feedback. I could no longer click any objects on the screen; without an external mouse, the laptop was unusable.

It was quite easy to solve that problem; some short notes might help you if you have a similar problem.

  • Fast fix: Activate “Tap to click”. Get a mouse and go to the Trackpad settings and set “Tap to click”. At least you can use the trackpad now with selecting things bei tapping them instead of clicking them.
  • It might not be the hardware’s fault. I did not realize it at once, but the click you feel when you click the trackpad is not produced by a mechanical spring but by activen electric components – a couple of small electro magnets producing the haptic feedback. This post by pocket-lint.com does a good job explaining the techonology. This means that it might actually a firmware or OS problem. I read that some people had success temporarily disabling all haptic feedback settings; give it a try.
  • It is quite possible to replace the trackpad if necessary. It is not really easy to take a modern Apple device apart, but it is feasible, provided you have the right tools. Remember that Apples patronizing “Genius Bar” technicians might charge you heavily. But: get the tools!
  • The right tools for fixing a Macbook Air. You will need them. I had Torx bits for mobile phone screws anyway and bought some more on Amazon. This is what you need:
    • a Pentalobe-P5 screwdriver for Apples 5-star-hole housing screws
    • a Torx-T4 screwdriver for removing the trackpad cable connector clamp
    • a Torx-T5 screwdriver for the trackpad screws
    • a magnifying glass
    • pincers
    • a box with several compartments to keep the 6 different types of screws apart and safe
    • good workplace conditions – proper lighting, enough space, a workplace mat
  • Taking the Air apart, step by step. ifixit does a brilliant job at explaining and showing every step – have the tutorial on a second screen next to your workplace so that you can look at every step when you need it. Pro tip: Read every step thouroughly before you do it – I didn’t at one point and missed that there are distance shims on top of the trackpad which drop to the floor when you take it out. Some rather undignified crawling ensued.
  • Apple supports your Right to Repair. Seriously. A little bit. „Right-to-repair“ laws have forced Apple to move. If you insist on trying to repair your iDevice, Apple gives you information, tools, and parts – provided that the iDevice is rather recent, and that you live in the US. But to be fair: You can find the comprehensive Macbook Air Servide Manual (PDF) for download. You may also order a replacement trackpad for about $100 in the U.S. Apple’s Service Support draws some criticism for its pricing and for its rather complicated procedures, but it is a start.

In short: This is what I did to get the trackpad working again

  • Bought the tools.
  • Opened the Mac and detached the battery connector. My advice: do that, then reconnect and check whether the trackpad is already working again.
  • Took out the trackpad and gave it some menacing looks, carefully poked at the metal strips, and cleaned what seemed worth cleaning.
  • Cleaned the trackpad bay in the housing to remove any object that might cause problems
  • Reinserted the trackpad. The service manual states that a new trackpad comes with shims in different thicknesses, so I measured the thickness of those I had and found that some were .1mm and some were .15. I inserted the .15mm ones to the front, and the .1mm ones up next to the keyboard.
  • Put everything back together. The critical moments: Reconnecting the battery connector with minmal force. Reconnecting the trackpad’s flat cable to the ZIP connector: open, pull out flat cable, reinsert, close locking mechanism. Reconnect the PCB connector plug for the trackpad next to the battery connector.
  • Triple-checked the connectors, then attached Macbook to power supply and switched it on. Worked.

Work in Progress: Trying out a new shop

Generated and (c) OpenAI Dall-E 2 AI

For years, I have been working with a shop plugin by maennchen1.de, wpShopGermany. It made things a lot easier and was worth its money, but there are a couple of issues I have with it:

  • Ease of use, as in: No…
  • Does not allow me to define the kind of invoice I would like it to
  • Problems with Paypal payments from the UK
  • Really, really dodgy translations.

These issues may not all be wpShopGermany’s fault, to be clear, yet I am trying out WooCommerce – and if that may that cause trouble and/or confusion: Sorry!

Generated by OpenAI’s Dall-E2 AI.

Price raise. Unfortunately.

The global chip crisis has reached my humble shop: When trying to source new programmable ROM chips – nearly all of Bob Grieb’s firmware updates use trusty old Atmel-27C256 PROMs that are still in production – we discovered that they have become much harder to get, and more expensive. Eventually we succeeded in finding a supplier who could help us restock in time, but the chips cost us over one Euro more.

Until further notice we will raise prices for firmware updates by € 1.50 after taxes per chip.

In spite of that: have a good start into 2022, the Year of Hope.

The Noisy One

I’ve won a Dreadbox Typhon in a sweepstake, and it’s bloody brilliant. Like, really, really brilliant! A fun machine with a monster sound and a great concept for real-time sound manipulation and editing. If there wasn’t that nasty problem with digital noise.

Dreadbox Typhon powered from USB hub; preset A1

Just listen to it! It’s wonderful – but you will have noticed the nasty sound on switching it on, and the permanent high-frequency noise. (Oddly enough, it’s no longer in the recording as soon as the sequencer starts, but believe me – it’s there, all of the time.)

Digital noise, for sure.

Continue reading

Stereoping Hardware Controller for Crumar Bit

Stephan (aka umusic6) did some nice work:

Thanks to his efforts, there is now a Bit Edition of Stereoping’s Synth Controller, for Crumar Bit-01/One/99 with the Tauntek firmware. You can read up on the firmware, or order it, here.

(No, this is not an affiliate link, I have no share in this. But I think it’s a great project.)

Howto: Replace the battery in an Oberheim Matrix-1000


A step-by-step description.

Why it is necessary

The Matrix-1000 was built in a time when there were no USB sticks and flash cards – the technology for storing small amounts permanently in electronics was a battery that kept the memory powered when the unit was switched off.

In the Matrix-1000, this is done with a very common type of battery – a CR2032 3-volt lithium battery, that has been working fine for more than two decades now but is destined to fail at last.

Unfortunately, one of the cost-cutting measures in the budget Matrix synth was to solder it in directly to save on the battery holder – so the replacement of the battery is a minor technical operation.

What you need to do it

  • A CR2032 battery – very common
  • A battery holder for the CR2032 – type for PCB through-hole soldering with 20mm pin distance (sample)
  • Soldering equipment for electronics: iron, solder, pliers, a good workplace light
  • Moderate soldering skills – soldering is no rocket science, but if you have never soldered before, maybe start by practising on an LED and a resistor
  • tweezers, a mechanical desoldering suction pump, desoldering mesh
  • A computer, or an iPad, with DIN MIDI to backup the sounds from memory

For good measure, you should consider replacing the firmware with Bob’s upgraded V1.20 as well.

The dangers

Replacing the battery is not hard, but there are some dangers involved, for you as well as for the old hardware.

  • Unplug the synth before opening it – do not electrocute yourself.
  • Avoid static charges (i.e. do not stroke your cat while repairing the synth) – static discharge can kill chips.
  • Avoid mechanical strain on the old PCB, and on the cables. Double-check whether you really removed all screws.
  • When replacing the firmware chip, be careful to insert the screwdriver blade between chip and socket, not underneath the socket. Do not scratch the PCB.

How to do it

  • Connect the Matrix to your computer and start a MIDI Sysex recorder (i.e. MIDI-OX on a PC or Sysex Librarian on the Mac). Select “Data Dump” on the Matrix, use the plus key to navigate to “2dA” (Dump All), press Enter. Stop recording when the Matrix is done.
  • Disconnect the synth from mains.
  • Remove the 9 screws from the lid, three on each side, three on the back. Remove the lid.
  • Cut the old battery from the board.
  • Desolder the remainder of the battery pins from the PCB; clean the PCB holes with the suction pump and/or desoldering mesh – this is the tricky part.

Although it might be possible to solder in the battery holder without removing the PCB if you are very skilled, it is probably easier to take the electronics board out:

  • Remove the 8 screws from the PCB, and the 5 screws holding the regulators to the right of the PCB to the cooling plate. Be careful not to lose the small distance discs from the PCB, and the plastic insulation on the regulator screws. There are also insulation layers between four of the regulators and the metal cooling plate – be careful not to remove those.
  • Remove the output connector to the back, and the PCB power connector to the right.
  • Put the battery holder into the PCB. The plus pole (the terminal on top) has to be facing the back of the synth, marked “Batt +” on the PCB.
  • Flip the board from the housing.
  • Solder in the battery holder from the back.
  • Check whether the memory chip – the one in the front left corner of the PCB – gets 3V in between pin 14 and pin 28.
  • Change the firmware EPROM by inserting a screwdriver blade betweet chip and socket, and wedge out the chip with great care. Avoid inserting the blade between socket and PCB, this might damage the PCB. When inserting the new chip, take care not to bend or fold any of its pins.
  • Reattach the PCB, and the regulators.
  • Close the lid.
  • Reconnect the synth.
  • Switch it on holding the ENTER key – this does a factory reset of the memory. You might have to redo this a couple of times.
  • Do a calibration run – navigate to EXT FUNC, select 7, ENTER, 0, ENTER. The display wil show CAL, the calibration takes about a minute.

The video of the process is quite detailed (i.e.: BOORING!), and it misses out the crucial detail of how to actually solder – the trick is that you use the soldering iron to heat up the wires you want to solder, and then melt the solder by touching those wires with it. The beginners’ technique of just holding the solder to the hot iron leads to ugly blobs of solder on your PCB. But if you really intend to watch this, you probably know how to solder anyway. (There is a short version of the video as well. With music!)