[Elecraft] K2 S/N 3594 - HELP!!!!!

[Sean Williams]

Hi Jim.

I must express my gratitude for your invaluable assistance in clearing the
fault I have experieinced during the build.

The fault was a small bridge on the mod board for rp3


My sincerest thanks

73
Sean
----- Original Message ----- 
From: "k4zm" <k4zm@comcast.net>
To: "Sean Williams" <m1ecy@uku.co.uk>
Sent: Wednesday, July 09, 2003 1:36 PM
Subject: Re: [Elecraft] K2 S/N 3594 - HELP!!!!!


> Sean:
>
> The voltage I find that might be a clue is pin 5 on U6 there should be 4.0
> volts at that point.  That point is just a voltage divider of two 10k
> resistor in RP3.  Also the voltage out of pin 13 on U4 should be at least
> 4.0 volts.I would look in the area of U6 and make sure all solder joints
are
> good and that it is not installed backwards...  Have you checked all the
> solder joints on each pin of the ICs in that circuit? (U3, U4 & U6)  The
0.0
> volts at pin 5 of U6 indicates a short of some kind.  With the power off
> check the resistance at pin 5 of U6 and see if you see close to 10K there.
> I am betting you will see a short which could be in the area of C93 or a
> short between pins 5 & 6 of RP3.  I  wish you were close by I would love
to
> find the problem for you. With your scope look at TP3 and TP1 and see if
you
> see a sine wave there. You will probably see one at TP3 but not at TP1.  I
> can't remember did your K2 pass the Ref Osc. Range test? You can also
check
> with a scope pins 1 and 4 for a sine wave.  I doubt that you will have a
> sine wave at TP1 since your internal counter is reading Zero.
>
> I hope this might be of some help.
>
> 73
> Jim Younce K4ZM
>
>
>