Moving resistors on a PCB?

Discussion in 'The Projects Forum' started by Kathy Rebecca, Dec 8, 2015.

  1. Kathy Rebecca

    Thread Starter New Member

    Oct 23, 2015
    I got a TRF7970AEVM for a project, but this is the first time I've ever worked with PCBs. I'm want to move the 0 ohm resistors so I can access one of the direct modes, but...I'm really not sure how to do so without damaging the board. So, how does one move components on a PCB?

    Here is a photo of the resistors I want to adjust.
  2. kubeek

    AAC Fanatic!

    Sep 20, 2005
    I can´t see any resistors except for R13 and 14 inside the red box, could you try and rephrase what you want to (i suppose) remove?
  3. paulktreg

    Distinguished Member

    Jun 2, 2008
    I see them! ;)

    Just dab your soldering iron on top making contact with both ends and I'm sure they'll come away easily.
    Kathy Rebecca likes this.
  4. kubeek

    AAC Fanatic!

    Sep 20, 2005
    OK after a second glance now i actually CAN see teeny tiny resistor between the pads.
    If you want to remove one, you got three methods that work for me.

    Method 1: if you got a fitting shape of the soldering iron, you may be able to grab the resistor with a tweezer and place the iron on it in such way that you are heating both ends at the same time, that should get it moving very easily.

    Method 2: since there are large pads and small component, with a clean soldering iron set to maybe up to 350°C without any solder added just heat one end, then the other, maybe repeat a few times, and see if the reistor can be moved with a tweezer. Use liberate amounts of flux.

    Method 3: this will get the nearby through holes clogged, but will make sure you can remove the resistor safely. Do the same as method 2, but add reasonably large amounts of solder to form a blob on each end, don´t fear filling up the holes. That will surely get you enough thermal inertia for the resistor to let go. Then use solder wick to clean those holes back again.

    Try in that order and see what gets the job done.
    Kathy Rebecca likes this.
  5. Kathy Rebecca

    Thread Starter New Member

    Oct 23, 2015
    Thank you!
  6. panic mode

    Senior Member

    Oct 10, 2011
    if you are not comfortable with soldering, consider removing resistors as mentioned by others and then soldering three rows of headers. then you can use standard jumpers any time you wish to make a change.

    pin header and jumper.png
    Kathy Rebecca likes this.
  7. SLK001

    Well-Known Member

    Nov 29, 2011
    The method I use for SMT resistors (and SMT devices in general), is to use TWO soldering irons with appropriate tips. Heat both ends and once the solder has melted, slide the component off its pads. I often use this method to work with SMT boards under a microscope.
    atferrari likes this.
  8. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    Many SMD resistors are small enough to lay a soldering iron tip across the body to heat both sides at once. This usually destroys the resistor (I would never reuse those) but gets them off. I keep a coat of fresh solder on my tip for better heat transfer.

    For any excess solder left behind solder wick works wonders.
  9. Colin55


    Aug 27, 2015
    Just use the soldering iron on one end of the resistor and then the other. The resistor will stick to your soldering iron. Pick the resistor off with your fingers and use it again.