CCFL VU meter

Discussion in 'The Projects Forum' started by funguypie2, Nov 22, 2012.

  1. funguypie2

    Thread Starter New Member

    Nov 22, 2012
    So i wanted to do a DIY project over the winter break where I make a bookshelf and put a VU meter up the sides of the shelf, at first I thought to use LEDS but thought it would be too hard to put the leds in the shelf. Then I found this schematic for a VU meter with CCFL's and was intrigued. Of course, knowing nothing about circuitry, I took it to my nearest radioshack and asked for some help, but the guy had lots of questions about the schematic.
    1. What does the from speaker terminals and J1 mean?
    2. is the capacitor a electrolitic or a ceramic disk, and is it 47 uf or 4.7 uf
    3. what does the 2m2 mean by R1
    4. what is the voltage of the op amp
    5. what is the ohm value of R4 R5 and R6
    6. what does the TO tube driver power input mean?
    heres the schematic link
    and the video where I got the idea from

    Thanks for all the help
  2. Dodgydave

    AAC Fanatic!

    Jun 22, 2012
    R4,5,6 are 22ohms each, the supply is 12volt, the capacitor is 4.7uF. R1 is2.2meg
  3. tubeguy

    Well-Known Member

    Nov 3, 2012
    J1 of the circuit connects to a speaker output on your stereo. 'To tube DRIVER..." connects to the power inverter supplied in the kit below.

    Capacitor is electrolytic. Note the + sign.
    It's 2M2 or 2.2 MEG (million) ohms. Big M means MEG, small m means milli.

    I type too slow
    Needs to handle 12VDC.
    22 ohms each, in parallel, 22/3 = 7.3 ohms, 8 ohm 1-watt OK also

    The circuit needs some 'tweaking' for safe operation with a powerful stereo.

    Check back later, Holidays...
    Last edited: Nov 22, 2012
  4. Audioguru


    Dec 20, 2007
    The polarity of the 4.7uF input capacitor C1 is BACKWARDS!