Results 1 to 9 of 9

Thread: adding potentiometers for scanning size (how to ? )

  1. #1
    Join Date
    May 2015
    Location
    belgium
    Posts
    21

    Default adding potentiometers for scanning size (how to ? )

    was searching for this and found this forum on google so decided to join and ask it here
    i am a laser hobbyist for a few years now and like to adjust my projectors.

    currently i have a projector but that does not have a size adjustment.
    on the inside i have the following signals:
    X+ GND X-
    Y+ GND Y-

    i assume it is possible to put a potmeter between these lines to adjust the scan angle?
    if yes what value should i have and how to connect it ?
    i think i need 2 potentiometers, one for each channel ?

    is the following correct? what do i do with the X- ?
    Click image for larger version. 

Name:	Untitled.jpg 
Views:	20 
Size:	47.3 KB 
ID:	47150
    Last edited by laserjohnn; 05-23-2015 at 10:32.

  2. #2
    Join Date
    Sep 2009
    Location
    Mexico
    Posts
    474

    Default

    You need two 10K ohm double pots for do this.

    One for + one for -
    like this.
    Pin 25 is GND

    Click image for larger version. 

Name:	pots.JPG 
Views:	50 
Size:	55.9 KB 
ID:	47151
    Last edited by megaton; 05-23-2015 at 12:40.

  3. #3
    Join Date
    May 2008
    Location
    Once it was called "Bel Paese" = ITALY
    Posts
    858

    Default

    I apologyze if I'm jumping inside discussion...

    What kind of 10kOhm double-pots have to be: Linears or logarithmics?
    my webpage
    http://stevemilani.jimdo.com
    Skype ID: stevemilani957

    my RGB analogue projectors:
    3.9 W (640/532/445) 30kpps
    2.6 W (655/532/450) 30kpps
    2.5 W (638/532/450) 30kpps
    0.7 W (test unit)(635/532/473) 18kpps

  4. #4
    Join Date
    Sep 2009
    Location
    Mexico
    Posts
    474

    Default

    Quote Originally Posted by Steve Milani View Post
    I apologyze if I'm jumping inside discussion...

    What kind of 10kOhm double-pots have to be: Linears or logarithmics?
    Linears, I think is best but not mandatory

  5. #5
    Join Date
    May 2008
    Location
    Once it was called "Bel Paese" = ITALY
    Posts
    858

    Default

    Quote Originally Posted by megaton View Post
    Linears, I think is best but not mandatory
    Ok... Thanks Mega!
    my webpage
    http://stevemilani.jimdo.com
    Skype ID: stevemilani957

    my RGB analogue projectors:
    3.9 W (640/532/445) 30kpps
    2.6 W (655/532/450) 30kpps
    2.5 W (638/532/450) 30kpps
    0.7 W (test unit)(635/532/473) 18kpps

  6. #6
    Join Date
    Sep 2009
    Location
    Mexico
    Posts
    474

    Default

    Quote Originally Posted by Steve Milani View Post
    Ok... Thanks Mega!
    Glad to help.

    Cheers,

  7. #7
    Join Date
    May 2015
    Location
    belgium
    Posts
    21

    Default

    Thanks megaton!
    but how do you decide the resistance value?
    as i also heard 50K or even 100K would do the trick.

    for the color modulation channel i could use single potmeters right ?

  8. #8
    Join Date
    Sep 2009
    Location
    Mexico
    Posts
    474

    Default

    Quote Originally Posted by laserjohnn View Post
    Thanks megaton!
    but how do you decide the resistance value?
    as i also heard 50K or even 100K would do the trick.

    for the color modulation channel i could use single potmeters right ?
    I also try 50k and 100k and work, but I have better results with 10k, mostly for the
    Color modulation, In my application 50k and 100k don't work properly,
    and YES I put single pots for this.

    I hope this is clear. My English is not my first language.

  9. #9
    Join Date
    May 2015
    Location
    belgium
    Posts
    21

    Default

    perfectly clear, thank you! works very good now

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •