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> To this day I wonder why Palm thought it was ok that all their LCDs emitted a high-pitched humming noise when turned on. Maybe it was designed by people who

• markrages 5y ago
  That was the era of the elecroluminescent backlight. This technology required a high-voltage (~100V) squarewave across the mostly-capacitive EL panel. This squarewave was at audio frequencies. The panel also happened to function as a piezo tweeter, depending on mounting. I worked for a cell phone company at the time. I have two memories of this technology: 1. Using the prototype phone out of its case and touching the 100 V squarewave to my ear. That's some tender skin... 2. Using a primary transformer in reverse as an audio transformer, to play the lab stereo over EL panel. It turns out the panel color changes a little bit with frequency.
  • causality0 5y ago
    So why didn't pocket pcs or non-Palm PalmOS devices have the same problem? All of the Palm units in my collection have the buzz but none of the Clies do.
    • omgwtfusb 5y ago
      They mostly used LCDs with LED backlights (not sure what they used the some early WinCE laptop style handhelds with color displays)
      • causality0 5y ago
        Yet another sad story. I wanted to love those but I couldn't put up with the passive-matrix display.