[Elecraft] K3 F Gain mod

[Dave - AB7E]

There are different methods used to solder SMT components to PC boards.  The use of adhesive under the body of the component is an older process typically used for wave soldering.  Reflow soldering is more common now (especially for single sided boards), where the solder paste is screened onto the board first and then the component leads are placed into the paste.  The sticky paste holds the component in place until the solder melts, at which point the surface tension of the solder takes over.

I'm pretty sure the K3 uses the latter technique and wouldn't have any epoxy holding the resistor to the board.

73,
Dave   AB7E



------Original Mail------
From: "Brian Alsop" <alsopb at nc.rr.com>
To: <elecraft at mailman.qth.net>
Sent: Fri, 29 Jan 2010 21:40:33 +0000
Subject: [Elecraft] K3 F Gain mod

The instructions have you clipping one SMT resistor and then removing 
the pieces.

I've did a trial of this method on a junk PCB here.

At least on the board I used, there apparently is some kind of adhesive 
under under the chip.  The clipping process seems to remove the solder 
resist and perhaps any PCB traces under the chip.

Is there anything under R8 that can be damaged?

(Guess not, since nobody complaining.  A blow up of the pix doesn't seem 
to show anything either)

73 de Brian/K3KO
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