FB3 QS 4,2v ON ILDA? (NOT 5v!)

Discussion in 'Lasershow Designer QuickShow' started by JORS, Jun 25, 2014.

  1. JORS

    JORS New Member

    Hi All,
    Just testing FB3 QS (usb) voltages for red/green/blue analog modulation on ILDA card and voltage is "only" 4,2v per color at full power (full brightness settings, full scale etc), NOT 5v
    Cause my Ld's drivers are adjusted for 5v modulation for full power, I can't obtain full laser power with ILDA :( on this config.

    I had to retouch bias/current trimpots on my laser drivers to obtain full laser power with 4,2v modulation, but this is annoying.

    My FB3 is connected to macbook pro running Windows 7 on parallels.

    Anyone knows why this happens?

    Many thanks!!
  2. Aaron@Pangolin

    Aaron@Pangolin Staff Member

    I suspect you have been measuring the color outputs with a meter rather than an oscilloscope. If you search on this forum, you will find that we have discussed this "issue" many times.

    They key is, that it's impossible to measure pulsed waveforms using a meter. And -- almost no matter what you do, the color signals will always be pulsed.

    Basically the only way you can measure the voltage level of the pulses is with an oscilloscope. If you look with an oscilloscope, you will find our voltage levels to be within spec.
  3. JORS

    JORS New Member


    OOh I see... many thanks Aaron :)