[Elecraft] ALC mod, Stereo speaker mod, pull-up resistor mod

[Monty Shultes]

I hesitate to write this for fear of scaring off some potential "modifiers", but the story is good and positive.

I did all 3 of these mods today. (The stereo speaker mod was outlined in a post from Wayne).  After reassembly the radio worked fine and I was able to set the amplifier ALC just right.

Then, after 3 hours, funny things happened. I could not change frequency.  I could not turn off the K3.  After disconnecting the power supply, the K3 came on with an "ERR PTT" message.  Looked it up in the manual.  Implicates the KIO3, where I had just made modifications.  I easily isolated the problem to the digital IO board.

Scanning the digital IO board with my illuminated magnifier I initially saw nothing.  Then, a faint shiny speck showed up on one of the 8 pin surface mount chips that was shorting two pins.  The offending speck was easily removed.  It had obviously been created during my mod work, and took 3 hours of aging before it would short out the pins, creating the problem.

I usually brush my circuit boards with a tooth brush after soldering to them. I did not do that this time.  I will do it next time.  All is well.

Merry Christmas/Happy Holiday Season to all Elecrafters.

Monty  K2DLJ
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