[Elecraft] Second call: K2 broken after KPA100 mod

[Don Wilhelm]

Steve,

There is no direct relationship between your symptoms and what you 
intended to accomplish.  So this is something that inadvertently 
happened along the way.

The first thing to do is inspect the control board visually - in most 
cases an unsoldered or poorly soldered connection is to blame for 
behavior like that.  Move things around a bit to see if you can make it 
change from working to not working.  Also check the soldering of the 
connectors at the front of the RF Board - they provide a path between 
the front panel and the control board.  Be certain the microprocessor 
(Control Board U6) is properly seated in its socket and no pins are bent 
under the chip (you may have to remove it to check for bent under pins - 
use good anti-static measures if you remove it).

If the problem does not reveal itself visually, the next step is to do 
DC voltage measurements on the control board and possibly the Front 
Panel board. Compare to the DC Voltage chart in the back of the manual.

Since you purchased a used K2, the level may be important - please let 
us know the serial number and state of updating that it may have had.
I am sorry I cannot provide a more concrete answer, but it does have 
nothing to do with the KPA100 installation at the point where you are now.

73,
Don W3FPR

Steve Kallal wrote:
> I was hoping someone would answer me on this one. The phone lines at
> Elecraft don't open until I am at work.
> 
> I am about done with part 1 of the assembly of the KPA100 option. I opened
> the K2 and removed pin 4 from P4 on the control board per the instructions.
> Rather than connect the partially assembled KPA100 to the K2, I powered up
> the K2 first. Now the K2 doesn't initialize.
> 
> Apparently my K2 is not completely broken. With the antenna hooked up, the
> receiver is definitely alive. It appears that the control board isn't
> functioning. The display stops ELECrAFt and doesn't go further. The tuning
> knob has no function. The S meter doesn't move. But sometimes signals are
> heard. I DON'T hear the 4 MHz clock in another receiver per the K2
> troubleshooting section.
> 
> I did the firmware reset hoping that might fix it. It didn't. I did have the
> CAL FIL BFO settings saved in a spreadsheet. But I didn't have any CAL PLL
> settings written down. Once the K2 is back, I'll have to learn that
> procedure since this is a used K2.
> 
> One definite repeatable symptom, is that the power has to be toggled on
> TWICE, before anything is displayed on the LCD.
> 
> Please I hope for some assistance here. It is probably a loose connection,
> but everything seems solid.
> 
> I will be emailing Elecraft support also.
>