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

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