I’ve hit a wall

Well i got started on the RF board and made it to the first power up test.  Everything seemed to go well but I’m not getting any display on the LCD.  Here is the email I posted to the elecraft reflector:

Hello all,

I finally made it to the first power up of my K2 and seem to have hit a snag.  
The radio powers up, The relays click and the backlight of the LCD comes on but no text.  After searching the list it seems that pin 1 of the driver is a likely suspect.  I took a look at it with a USB microscope and it looks like the solder joint there is fine.  I posted a picture of it here: https://flic.kr/p/P3Esg4
Here are the steps I’ve taken so far:
  • I reflowed a few of the pins that looked suspect going from the LCD to the driver IC
  • Checked the values of R15 and 16 they both test as the correct values
  • I show fluctuating voltage on pins 16 and 17 indicating data is present 
  • Pulled the Driver IC and tested continuity from pins 1 and 2 to the rf board connector pins 16 and 17
  • Further tested continuity from lcd controller pins 1 and 2 all the way back to pins 38 and 39 on the MCU 
  • Confirmed proper voltage to the MCU (5V) and I do hear the oscillator @ 4Mhz
  • Confirmed I am getting 5v at the voltage regulator on the control board and that is making it to the front panel board 
I’m not sure what else to test now.  One thing that is mentioned in the troubleshooting is if the bargraph is also not working to check the 5V line.  Should the bargraph be lit at all during power up?  Maybe that’s a clue?  I would like make sure I’m getting the 2V? to the LCD driver but when everything is assembled I cant get at that pin. 
Thanks for any and all help!
Robert
AD0TA 

Someone recommended that i contact elecraft support so I’ve sent an email to them as well.  Here’s hoping I get a response soon.  I haven’t had much time to work on the radio lately but Sunday was a good long troubleshooting session and I figured I would post about it.

 

 

 

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