Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 73,649   Posts: 1,623,525   Online: 860
      
Page 1 of 3 123 LastLast
Results 1 to 10 of 23
  1. #1
    hrst's Avatar
    Join Date
    May 2007
    Location
    Finland
    Shooter
    Multi Format
    Posts
    1,300
    Images
    1

    Corona treatment system works!

    http://www.youtube.com/watch?v=StgbV766dqQ

    As you can see, it works! --- finally!

    I'll publish instructions to make one later, however this project needs some understanding of electronics and is somewhat dangerous

  2. #2
    Jerevan's Avatar
    Join Date
    Nov 2004
    Location
    Sweden
    Shooter
    35mm
    Posts
    1,903
    Images
    9
    Yeah, the Super Killing Machine HRST 2001 PRO is working! It looks seriously dangerous, like sticking a screwdriver into an TV set or something.

    Great stuff.
    “Do your work, then step back. The only path to serenity.” - Lao Tzu

  3. #3
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    24,097
    Images
    65
    Congratulations.

    I am interested in the voltage and amperage used as well as any other details you might wish to share.

    Thanks.

    Be careful.

    PE

  4. #4
    dehk's Avatar
    Join Date
    Aug 2010
    Location
    W Michigan
    Shooter
    Multi Format
    Posts
    889
    That, is awesome.
    - Derek
    [ Insert meaningless camera listing here ]

  5. #5
    hrst's Avatar
    Join Date
    May 2007
    Location
    Finland
    Shooter
    Multi Format
    Posts
    1,300
    Images
    1
    Quote Originally Posted by Photo Engineer View Post
    I am interested in the voltage and amperage used as well as any other details you might wish to share.
    Mains voltage (230 VAC) is rectified and filtered with capacitor to 320 VDC, which is then chopped to 26 kHz square wave by using a H bridge of four MOSFETs, which is fed to a self-made transformer with 60 turns in primary winding and 600 turns in secondary winding. Current-limiting resistor is in series with primary winding, limiting it to about 2 A in case of accidental arcing.

    The result seems to be around 4.8 kV(rms), 26 kHz, and can give 200 mA of current with the series resistor, or more if it's removed. Of course using such a small electrode, it won't take this much current, but it's good to have some reserve in the power supply. In fact, I think this could supply a kilowatt or more...

    Electrode is just an aluminium tube, with PVC tape in both ends to create the air gap of about 1 mm in the middle. The ground plate should be covered with some dielectric that prevents arcing if you want to treat the edges, too.
    Last edited by hrst; 11-10-2010 at 04:00 AM. Click to view previous post history.

  6. #6

    Join Date
    Feb 2008
    Location
    Greece
    Shooter
    35mm
    Posts
    1,322
    Quote Originally Posted by hrst View Post
    Mains voltage (230 VAC) is rectified and filtered with capacitor to 320 VDC...
    Ah, that's the huge black cylindical thing eh?

  7. #7
    hrst's Avatar
    Join Date
    May 2007
    Location
    Finland
    Shooter
    Multi Format
    Posts
    1,300
    Images
    1
    Quote Originally Posted by Anon Ymous View Post
    Ah, that's the huge black cylindical thing eh?
    Yeah. 450V 1000 µF IIRC. Smaller (around 300 µF) would do but had those lying around at the club...

  8. #8
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    24,097
    Images
    65
    Very nice. I'm looking forward to seeing some coatings made on the surface you create. Remember that this can cause fog if it is too "heavy" and stripping of the emulsion if it is too "weak".

    PE

  9. #9
    Nicholas Lindan's Avatar
    Join Date
    Sep 2006
    Location
    Cleveland, Ohio USA
    Shooter
    Multi Format
    Posts
    2,381
    Images
    4
    Very nicely done.

    A cheap source of high voltage, though it is at line frequency (or DC, if you wish), is the transformer, rectifier and capacitor from an old microwave oven. With a pair of voltage doublers made from more microwave rectifiers and capacitors it is possible to get 8kV at pretty hefty power levels.
    DARKROOM AUTOMATION
    f-Stop Timers - Enlarging Meters
    http://www.darkroomautomation.com/da-main.htm

  10. #10
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    24,097
    Images
    65
    Do a patent search for "corona" and "kodak" and you will find about 1700 hits with extensive descriptions and a list of the problems that must be solved such as uneven corona and ozone removal. The wear of the discharge system and type of "wire" used is also important. Just some thoughts you may want to look into. I don't want to discourage you, just inform you of the mass of data out there and the lists of potential problems.

    Again, best wishes and it was a job well done! Congratulations.

    PE

Page 1 of 3 123 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin