Repairing the PCB of the K2

[stephen Farthing]

Hi Guys,

 

            Due to my clumsiness in removing my blown finals I have managed
to damage the PCB of my K2. I managed to remove half of the land for the
Base of Q7 on the top of the PCB, and slightly lifted the land for the
emitter of Q8 on the underside of the board. I still have continuity between
the undamaged lands and the components they connect to. So, the issue I have
it to fix the damage or leave it be and point to point wire the links.  I
have available a Chemtronics Conductive pen which can be used to repair
boards and the thought I have is to clean up the board as best I can, use
the pen to replace the lands, check for continuity and refit the PA
transistors. However as I have never done this before I am not sure if it
will work. Does anyone have any advice please?

 

            Second point, JABDOG in the UK stock replacement PA transistors
for anyone over here who needs them over this side of the pond

 

            Third point, I would not have been in this mess had I double
checked the connections when testing the 160 meter option and not had the
dummy load in the wrong antenna connection. I transmitted into no load and
blew the finals.

 

            Lastly, I think one of the reasons I damaged the PCB is that I
was using my normally trusty old weller Iron which must be 30 years old. It
seems not to be as good as before and I suspect the temperature regulation
is awry. So I shall pension it off to the workshop and purchase a new iron.

 

            The sun is shining in my part of England and I have put up a
temporary horizontal loop antenna with about 50 meters of twin lead.it works
FB.

 

73 from England

 

Steve G0XAR

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[Don Wilhelm-3]

Steve,

I am not familiar with any of the board repair materials, so without any
experience with them, I would go the safe route and add wires to whatever is
left of the PC traces - scrape off the green solder mask to solder the wire
onto the remaining trace or run full length point to point wiring - either
should work fine.  You have obviously destroyed the thru-plated holes, so be
certain all components are connected - you may have to do the repairs to
both sides of the board - fortunately with the PA transistors that should be
easy to accomplish.

If you have damage to the collector or emitter pads, definitely use the wire
to handle the current that must flow there - the conductive pen stuff may
not handle much current.

73,
Don W3FPR

> -----Original Message-----
>             Due to my clumsiness in removing my blown finals I
> have managed
> to damage the PCB of my K2. I managed to remove half of the land for the
> Base of Q7 on the top of the PCB, and slightly lifted the land for the
> emitter of Q8 on the underside of the board. I still have
> continuity between
> the undamaged lands and the components they connect to. So, the
> issue I have
> it to fix the damage or leave it be and point to point wire the links.  I
> have available a Chemtronics Conductive pen which can be used to repair
> boards and the thought I have is to clean up the board as best I can, use
> the pen to replace the lands, check for continuity and refit the PA
> transistors. However as I have never done this before I am not sure if it
> will work. Does anyone have any advice please?
>
>

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