[Elecraft] Building a K2, Does anyime have a set of rework e

[Don Wilhelm]

Harry,

If you are ordering the options you want to include with the K2, there 
is little need for the Rework Eliminators.  There is very little rework 
when adding options - the "Rework" consists mainly of removing the 
jumpers that are normally installed when building up the basic CW K2 and 
removing/changing at most one capacitor for each option (the KNB2 
requires 3 resistors to be changed).  A careful perusal of the 
installation procedure in the manuals for the options that you wish to 
add.  The headers required come with the options that you purchase 
initially.

For those options that you may want to add later, it is a simple matter 
to install the female headers on the RF board and Control Board and use 
wire jumpers, and perhaps a capacitor or two in place of the actual 
rework eliminators.  Download and identify the headers required.

The most complex part of the rework eliminators is the KNB2 and the 
K60XV.  I do not recommend making the board changes (C71 value and 
D19/D20 addition) until you actually have the K60XV option ready to 
install.  The "Rework Eliminator" boards that you need are easily 
fabricated on perfboard and strips of male pins.

For the K160RX, you need only the header and a bent component lead for a 
jumper - stick the jumper wire in the header and do not install W1.
For the KAF2, you need only the 3 pin and 5 pin female headers mounted 
on the Control Board - do not install the wires for R18 and R19, but 
stick jumper wires made from component leads into the headers.
For the KNB2, you will need the perfboard and 8 pin male header - on the 
RF board install a 2.7k resistor at R88 and a wire at the R89 location. 
Your plug-in "eliminator" needs 3 resistors - a 470 ohm, a 100 ohm and a 
680 ohm.  The 470 ohm resistor goes between pins 1 and 5, the 100 ohm 
resistor goes between pins 1 and 6, and the 680 ohm resistor between 
pins 6 and 5.
For the KSB2, you need to install 3 pin headers at J9 and J10 and a 12 
pin header at J11.  bend 2 wire jumpers to plug into J9 and J10 - from 
pin 1 to pin 3 (do not install W2 and W3) and on a 12 pin male header 
strip on perfboard solder a .001uF capacitor between pins 7 and 12 - do 
not install C167.

That takes care of all the "homebrew Rework eliminators" except the 
K60XV option.  Since I do not recommend installing that until the K60XV 
option is built and ready to install, I have left that off the list. 
The VFO and PLL R30 voltages change with the addition of the K60XV 
changes and cannot be properly tested until the K60XV option is actually 
installed.  If you want to do a partial install of the K60XV, put a 3 
pin female header at J15 and put the leads of the 4.7pF capacitor into 
pins 1 and 3 of that header rather than soldering it to the RF board. 
You can also install the 8 pin female header at J13 and put a wire 
jumper between pins 3 and 5 (leave out W6 jumper).  BUT change the value 
of C71 and add D19/D20 as well as the coax cable only after you have the 
K60XV option built - that is only one capacitor to change.

If you want to install the headers at P3 and P6, you can do that at any 
time - no jumpers are required - one header is supplied with the KAT2 
option and another with the KBT2 - both are supplied with the KPA100 kit.

So there you have the complete instructions for installing the "Rework 
Eliminators" without buying the full kit.

73,
Don W3FPR

On 1/27/2017 6:28 PM, Harry Yingst via Elecraft wrote:
>
> I decided to build another K2 (since I foolishly sold my first one) I figured this time around I would use some Rework Eliminators.
>
> When I checked unpcb.com I found that they no longer stock them.
>
> Does anyone have an unused set with the additional components (full kit) that they want to sell?
>