Re: Re: New Backlight - inverter problems

Good information.  My Nightlaunch backlight is still going strong on my other gear, and I suppose I should get one for my K5.  First I will try the re-solder thing since the Kawai tech support guy told me the same thing.  Can I find the inverter easily?  Is is connected directly to the backlight?   
Didobrain
  ----- Original Message ----- 
  From: nelsonj_sce 
  To: [email protected] 
  Sent: Tuesday, September 14, 2004 11:57 PM
  Subject: [k5synth] Re: New Backlight - inverter problems


  Update:
  Well today I ordered a new inverter from www.DigiKey.com.  I found an
  inverter that looks like it will do the job - for those interested it is:

  Digikey part #      289-1032-ND  and it only cost $11.90 - not bad.

  I am not sure if it will fit exactly in the same slots as the original
  inverter so it might require some additional wiring.

  Anyway, I had my K5 open to look at the power supply to plan the new
  inverter install when my K5 started "humming", and guess what, I now
  have a beautiful blue backlight.  It looks great, a very cool blue. 
  So it appears my inverter was not bad, but it just has bad solder
  joints.  It is working for now but tomorrow I will likely take out the
  board and redo all the solder joints.  

  Just some additional info I learned in researching backlights and
  inverters.  The "brightness" of the backlight is a function of the
  voltage and frequency applied to the backlight.  It appears one has a
  lot of flexibility in selecting the inverter output voltage and freq.
  For example, nightlauch says you can "test" the backlight by plugging
  it directly in to a wall socket (120V AC @ 60 Hz here in the US)!  The
  higher the voltage and freq the brighter the backlight.   However, the
  backlight will "burn out" quicker the higher the freq.  So there is a
  trade off, high freq = bright but shorter life.  

  Right now my stock inverter is putting out about 102V @ 380 Hz.  I
  think the inverter I ordered will put out about 95V @ 540 Hz and
  should work with a 3 - 6 V DC input.

  Next step, 147k resistors (also ordered from Digikey today).  



  --- In [email protected], "nelsonj_sce" <nelsonj_sce@y...> wrote:
  > Well I replaced my backlight with one I ordered from
  www.nightlaunch.com.
  > 
  > It took less than two weeks from when I ordered and the parts look
  good.  
  > 
  > Good news/bad news though on my backlight.  
  > 
  > The good news:  I had no problems removing the LCD, taking out the old
  > backlight and sliding in the new backlight.  The new light has some
  > wires and a plastic "tab" that kind of gets in the way, so I soldered
  > the backlight wires to where the wires connect to the LCD board. 
  > Hint:You have to cut the new backlight to size, so make the backlight
  > a little longer (say 1/4 inch) than the original to make things easier.
  > 
  > Bad news: My backlight does not work but I think my inverter is the
  > problem.  I am only getting about 1/2 Volt at the output of my
  > inverter, and I am supposed to get 120V @400Hz if I understand the
  > part correctly.  I tested my inverter before I did the backlight
  > install and saw it had low voltage, but I was hoping that my existing
  > "dead" backlight was causing the problem (i.e. it was shorted.) I
  > guess not because even with the new backlight I get very low voltage.
  > 
  > Anyway, it looks like I need to get an inverter.  I can get an
  > inverter from nightlaunch for $17.99+s/h but it needs 9V DC.  I
  > understand the inverter in the K5 uses 5V DC. 
  >  
  > Q1: Does the K5 inverter use 5V DC?
  > Q2: If I measure the voltage on the two wires to the left of the
  > inverter, should I get 120V if everything is working? (My Fluke says
  > it is good <=1kHz)
  > Q2: Does anyone know where to get a compatible K5 inverter and how
  > much it will cost?
  > 
  > Thanks again for all the help.  This group is great.


        Yahoo! Groups Sponsor 
              ADVERTISEMENT
             
       
       


------------------------------------------------------------------------------
  Yahoo! Groups Links

    a.. To visit your group on the web, go to:
    http://groups.yahoo.com/group/k5synth/
      
    b.. To unsubscribe from this group, send an email to:
    [email protected]
      
    c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.