[Elecraft] K2 heatsink lock washers

[Don Wilhelm]

Chuck,

Opinions on this vascillate with time.  The fact is that the toothed
lockwashers will tear out bits of aluminum when they are removed.  Those
bits can drop onto the thermal pads and become embedded which can cause a
collector to ground short at the PA transistors.  Replacing the toothed
lockwashers with the split variety will considerably lessen the metal
tear-out.

On a routine basis, I replace the toothed lockwashers with the split ones on
any K2 that I remove the heatsink - just because I consider it good
practice.

You can replace the lockwashers, but OTOH, if it ain't broke, don't fix it.

73,
Don W3FPR

> -----Original Message-----
>
> The K2 is progressing nicely.  Yesterday, I had quite a bit of
> time to work on it and installed the internal battery & speaker,
> the K160RX module, and the KDSP2.  These all checked out fine.
> The rework eliminators and instructions were quite helpful in
> getting these options incorporated.
>
> I especially appreciated not having to remove the heatsink in
> order to install the 160 meter module.  This raises one question,
> though.  The instructions for the K160RX say to replace the
> toothed lockwashers for the PA transistors with split lockwashers
> provided in the 160 meter kit.  Why is this?  How important is
> this?  I do plan to replace the lockwashers if and when I remove
> the heatsink, but I saw no reason to go out of my way to do this.
>
> 73,
> Chuck  NI0C
> (putting finishing touches on K2 s/n 5853)
>
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.5.432 / Virus Database: 268.15.9/571 - Release Date: 12/5/2006
11:50 AM