K2 No LCD display

[Robert Forster]

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

--
===
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[Don Wilhelm]

Robert,

Is this a new K2 that uses the new VFO encoder mounted on a board?
If so, the most likely problem is that the encoder board is contacting
the back of the Control Board.

Flush cut *all* the leads on the encoder board - really flush with the
board.
Then also flush cut the leads on the Control Board that might contact
the encoder board.
Put some electrical tape over the encoder board and see if it works.
In extreme cases, a better insulator such as fish paper or some other
plastic insulator may be required on the encoder board.

You can gain extra space between the encoder board and the Control Board
by placing the lockwashers for the Front Panel standoffs between the
rear of the Front Panel Board and the standoffs instead of behind the
screwheads.

Make certain the pads between the top rear of the Front panel board and
the 2D connectors are properly in place.

73,
Don W3FPR

On 11/13/2016 6:35 PM, Robert Forster wrote:

> 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
>
>

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