FPVLAB

image
Page 7 of 12 FirstFirst ... 56789 ... LastLast
Results 61 to 70 of 119

Thread: Lawmate 2.4gHz 500mw Tech

  1. #61
    Navigator
    Join Date
    Jan 2012
    Posts
    10

    Lawmate 2.4gHz 500mw Tech

    In the Builds, Tuning & Modifications section, there are two different approaches to improving the cooling of the Lawmate VTx, one simple, one more challenging. I did the more challenging approach. I discovered a few things along the way that might help out.

    First, don't remove the SMA connector. It's a pain to solder it back on the case. I discovered that the center pin of the connector and the plastic around it can be pushed out of the SMA housing from the back side. I didn't get to try this, but it is probably a simple matter of heating the solder on the center pin while pushing on the plastic to move it off the PC board.

    The second thing I noticed is that, in the TBS instructions, there is a copper heatsink glued to the bottom of the PCB. In my case, there was no heatsink at all! It was just a blob of solder. I'm guessing they've changed their manufacturing process? I cleaned it off and cut out a piece of copper from an old video card heat sink that fit perfectly. Soldered it to the PCB and applied Arctic Silver, as instructed.

    When it came time to close up the case, I thought about the alternate "simple" mod on the TBS web page, which was to use heat transfer glue to attach a copper heat sink to the top of the chip. Instead of doing that, I cut out another piece of copper (it just happened to be the right thickness) and soldered it to the top of the case. Instead of having to mess with glue, I just had to apply more Arctic Silver to the top of the chip and I was done. One thing to be careful of is to leave a little bit of a gap where the copper meets the side flange of the top of the case. (see the attached picture) That gives clearance when you attach it to the bottom of the case. So now, the chip is sandwiched between two pieces of copper connecting it thermally to the top and bottom of the case. I'm planning to move the external heatsink to the bottom of the case, as with the "challenging" approach, since there is more surface contact with the case, and I suspect the PCB was designed for the heat to transfer off the chip through the bottom.

    Hope this helps!
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Lawmate Heatsink 1.jpg 
Views:	251 
Size:	97.8 KB 
ID:	5912   Click image for larger version. 

Name:	Lawmate Heatsink 2.jpg 
Views:	196 
Size:	97.7 KB 
ID:	5913  

  2. #62
    Altitude Junkie Greg's Avatar
    Join Date
    Jun 2011
    Location
    Coral Springs, Fl.
    Posts
    979
    Does anyone know what the small POT does on the lawmate vTX? The one that is exposed and next to the input jack.

  3. #63
    I Like Waffles... SENTRY's Avatar
    Join Date
    Feb 2011
    Location
    Atlanta, GA
    Posts
    10,849
    Quote Originally Posted by GregSilver View Post
    Does anyone know what the small POT does on the lawmate vTX? The one that is exposed and next to the input jack.
    The audio pot?
    "I Like Waffles" : FPVLab on Facebook and FPVLab on Twitter

  4. #64
    Navigator maurof78's Avatar
    Join Date
    Feb 2012
    Location
    Chicago
    Posts
    29

    first test

    hey guys,
    I just set up the Lawmate and I'm not really able to get a clear picture. Could this be due to bad wiring? Interference? Thanks very much for your help!



    PS: Please let me know if I should post this somewhere else and I will remove.
    Last edited by maurof78; 2nd March 2012 at 12:45 AM.

  5. #65
    FPV Addict Scotttu's Avatar
    Join Date
    Dec 2011
    Location
    Silverdale, WA, USA
    Posts
    9,997
    Walk that camera and VTX about 20 feet away and try again.
    "Truly superior pilots are those who use their superior judgment to avoid those situations where they might have to use their superior skills"- Author unknown

    KF7TRX

  6. #66
    Navigator maurof78's Avatar
    Join Date
    Feb 2012
    Location
    Chicago
    Posts
    29
    Quote Originally Posted by Scotttu View Post
    Walk that camera and VTX about 20 feet away and try again.
    Walked it all around. About 20 ft at the most and the image does not change. I made sure to turn off the wifi at home in case it would cause interference. I do still see four wifi networks available from neighbors though. Could that be the cause? -or does it seem like a connection problem? Thanks!

  7. #67
    on a vacation brosius85's Avatar
    Join Date
    Jun 2011
    Location
    bathurst nsw
    Posts
    2,250
    try all channels make sure you have correct antennas try a different display and try a different environment. last thing i would try is sheilding different components with tin foil.

  8. #68
    I Like Waffles... SENTRY's Avatar
    Join Date
    Feb 2011
    Location
    Atlanta, GA
    Posts
    10,849
    Have you adjusted the A/B switch?
    "I Like Waffles" : FPVLab on Facebook and FPVLab on Twitter

  9. #69
    Who I am^^ Stuff I Say>> Reverand Blue Chip's Avatar
    Join Date
    Feb 2011
    Location
    Orlando Flori-Duh
    Posts
    1,366
    Quote Originally Posted by SENTRY View Post
    Have you adjusted the A/B switch?
    AB switch don't do shit.
    "He who turns himself into a beast gets rid of the pain of being a man. I became the God Damn Honey Badger." Visit me on YouTube "BlueChipFPV"

  10. #70
    Navigator maurof78's Avatar
    Join Date
    Feb 2012
    Location
    Chicago
    Posts
    29
    Thanks for the advice. I tried it with a different display. Regardless of channel the image looks similar. The AB switch did not seem to do much. The antennas I am using came with the equipment.

    EDIT: After redoing the wiring I am noticing that the issue is with the audio connection. If I disconnect the audio I get a clear image. When I connect it again the picture is fuzzy again... Any thoughts? Thanks!
    Last edited by maurof78; 2nd March 2012 at 03:42 PM.

Page 7 of 12 FirstFirst ... 56789 ... LastLast

Similar Threads

  1. 2.4 GHz 500mW - Lawmate vs. ImmersionRC?
    By JBeloncik in forum IFR - Video Link Discussion
    Replies: 72
    Last Post: 11th April 2013, 12:35 AM
  2. Lawmate 2.4gHz 500mw Tech
    By Keith in forum RC TECH
    Replies: 60
    Last Post: 8th January 2012, 07:45 PM
  3. LawMate 500mW 1.2/1.3ghz
    By Hga77 in forum IFR - Video Link Discussion
    Replies: 7
    Last Post: 30th November 2011, 10:19 PM
  4. Lawmate 1.2Ghz 500mW ???
    By marcin.gala in forum RC TECH
    Replies: 1
    Last Post: 15th October 2011, 05:04 PM
  5. lawmate 2.4 500mw dead?
    By w4Rd3n in forum RC TECH
    Replies: 3
    Last Post: 3rd August 2011, 02:06 AM

Tags for this Thread

Posting Permissions

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