Watchmaking The course

TL Micro: the timegrapher microphone's user guide

TL Micro · user guide

The microphone that listens to your watch.

The TL Micro picks up your watch's tick and sends it to the timegrapher in your student area: the rate, the beat error and the amplitude, on your computer. It is sold with the online watchmaking course.

Open the timegrapher The user guide

The timegrapher opens in the student area, with the code you received when you bought the course.

User guide

  1. Plug it in

    Plug the TL Micro into a USB port of your computer (Mac, PC or Chromebook), with a USB-C adapter if your computer only has that port. There is nothing to install: the computer sees it as a microphone, often named "USB Audio Device". On a phone or tablet it works if the device accepts a USB microphone; a computer is more comfortable.

  2. Open the timegrapher

    Scan the QR code on the microphone, or open tl-watchmaking.com/micro, then "Open the timegrapher". Enter your student code if the area asks for it. Chrome, Edge and Firefox work best.

  3. Allow the microphone

    The browser asks for the microphone: allow it. Under "Microphone", choose the TL Micro (USB Audio Device), not the computer's built-in microphone. The sound is analysed on your device and sent nowhere.

  4. Choose the calibre

    Type your watch's calibre: the lift angle and the beat rate fill in. If it isn't in the list, the page counts with 52°, the most common value: the rate and the beat error stay right, only the amplitude is approximate. Leave "Beats/hour" on auto: the page finds the beat rate by listening.

  5. Put the watch on

    Wind the watch: about twenty turns of the crown for a hand-wound watch, or wear an automatic for a few hours. Put it on the sensor, the caseback well in contact, without clamping it harder than needed. While it measures, touch neither the table nor the cable: a knock sounds like a beat.

  6. Listen

    Click "Listen". The level sets itself. The page first lets the signal settle, about fifteen seconds, showing nothing, as a Witschi does; then the figures come.

  7. Read the figures

    Rate, s/day
    How much the watch gains (+) or loses (−) in a day.
    Beat error, ms
    The difference between the tick and the tock. Under 0.6 ms is good.
    Amplitude, degrees
    How far the balance swings. Wound, dial up, most watches show between 250° and 310°. Under 200°, the watch needs a service.

    The ⌀ average button picks how long the average runs (1 to 60 s); the instant value stays underneath. The ♪ sound button lets you hear the beats.

  8. Measure in the positions

    Pick the position the watch is in, wait for about twenty seconds of measuring, then "print": the page keeps the mean and tells you how to turn the watch for the next one. Do at least two, dial up and crown down; all six give the full spread between positions.

  9. Regulate

    First the beat error (the stud carrier), then the rate (the regulator), then check in the positions. The course's regulating chapter shows it step by step. A low amplitude or a large spread between positions can't be regulated away: the watch needs a service.

If it doesn't work

  • No beats: check that "Microphone" shows the TL Micro; unplug it, plug it back in and reload the page. Is the watch running? Wind it.
  • The browser refused the microphone: click the padlock left of the address, allow the microphone, then reload.
  • The signal clips: lower the TL Micro's input level in the computer's sound settings (Mac: System Settings › Sound › Input; Windows: Settings › Sound › Input).
  • The figures jump: a steady table, away from vibrating machines, the cable free; use the 10 s average.
  • No sound: click "allow sound" beside the ♪ button.

Good to know

  • The rate and the beat error are right; the amplitude stays an estimate, which depends on the lift angle.
  • The page checks the sound card's clock against the computer's time by itself; after a quarter of an hour, the rate is right to a few tenths of a second a day.
  • It is a tool to learn and to regulate, not a workshop instrument like a Witschi.
  • Keep the TL Micro dry, the cable without tight bends; a dry cloth is enough to clean it. It has no battery and nothing to adjust.
  • A question: write to me from your student area.

Open the timegrapher

Contact

Write to me.