[Elecraft] Need a little SMD help!

[Don Ehrlich]

Hank,

Sorry that I am not a little closer.  However, I recently replaced my diodes 
(using the SMT parts .. but the leaded types will install just as easily) 
and the only tricky part is getting the old ones off of the board.  I 
received a lot of advice from the list and the method I found easiest is 
described below.

First .. I want to note that the SMT diodes that are installed originally 
have three solder tabs but one of them is a dummy with no connection.  Also, 
those the bodies of those SMT parts are slightly elevated off of the board 
.. the space is too small to be visible but it is there (at least it was on 
my board) and it came in handy when lifting the old parts.

I was advised to heat the diodes evenly using a large blob of molton solder 
on the tip of my iron and touching the top of the diode with the hot solder 
blob.  That did not work, perhaps because my soldering iron tip was not big 
enough.  Then I tried slipping a very very thin piece of steel sheet under 
the diode while heating first one side of the diode and then the other.  The 
perfect piece of thin steel is a  0.002 feeler gage that is part of an 
assortment of feeler gages used by mechanics for setting spark plug or valve 
lifter gaps.  Many of us have them in our tool box.  That feeler gage worked 
very well because it nested under the edge of the diode before I had touched 
it with the iron and it lifted the diodes easily leaving the pads looking 
like new.

For what it's worth ...

Don K7FJ


I need a little help with replacing the two SMD diodes in the VSWR circuit.

K3 support has determined, after 4 days of emails, that they are bad - 
possibly from a 'nearby lightning strike' - and it's up to me to replace 
them with 2 new more robust diodes or pay for having them replaced if I send 
them the K3.  I guess the new robust parts are warranty, but replacing them 
isn't!

Elecraft is sending me the 2 new more robust diodes.   I do not have the 
equipment to remove the old ones and replace them, nor do I have the desire 
to work on anything smaller than a 1/8 watt resistor.

So ..... is there anyone within 50 miles or so of Lapeer, MI who can change 
these new diodes when I get them?    And if you don't have a K3, this would 
be a good chance to see one and try it out!

73    Hank    K8DD