[Elecraft] First Alignment and Test problem #5703

[Dave Sergeant]

On 26 Aug 2006 at 4:02, W3FPR wrote:

> 
> One often repeated error in assembly is failure to solder pin 1 of the Front
> Panel U1 socket - result is a blank display.
> 
> Peer carefully under the LCD and backlight assembly and see if pin 1 is
> soldered.
> If it is not soldered, therre is a way to solder it without removing the LCD
> (which is a nasty task) - cut away a small portion of the plastic outside
> pin 1 (cut at the bottom of the socket), so you can place the tip of the
> soldering iron on the pin from the socket side while feeding a bit of solder
> on the other side of the board.
> 
> You may want to vow to always solder IC pin 1 first on all ICs during your
> assembly.  The pad for pin 1 is round as a unique marker while the others
> are square.  Sometimes the eyes miss that single round pin.
> 
> 73,
> Don W3FPR
> 

Well I reached the same point in the assembly of #4848. I had just 
read your posting and said 'well at least I won't make that mistake' -
 I am a seasoned builder and this is my second K2.

Guess what, switched on for the first stage testing and lcd lit up, 
relays clicked but no display. Did a bit of tracing, got my dmm out, 
and you guessed it, pin 1 of U1 was not connected!!

To avoid dismantling the front panel assembly and not wishing to 
mangle the ic socket I added a wire link soldered directly to U1 
itself and to the lower end of R7.

K2 now working fine at stage 1.

73 Dave G3YMC



http://www.davesergeant.com