COHERENT CW NEWSLETTER (Copyrighted June, 1975) CCWN 75:17

 ASSEMBLY AND OPERATION OF THE COHERENT CW FILTER RAYMOND C.
PETIT, W7GHM
 
    The CCW filter prototype board is a 3.2 by 3.7 inch
double-sided  card with mounting holes on a 2.7 by 3.2 inch
rectangle, suited for  size 6 screws. The board fits easily in a
Bud Radio model CU234  "Econobox" complete with the phase-select
switch and all external  connections.  Refer to the Figure 1 of
the board and make the following modifications to the circuit
board before mounting components.      
   a. Cut away the ground planing around the circled pad, so 
that this pad is isolated from ground.     
   b. Cut the plating between the two pads as marked.          
Since this board is double-sided, but does not have plated-
through holes, it is necessary to solder connections on both
sides of the board. Use a very small, low-power soldering pencil
for this work. If you wish to use sockets for the IC's, and I
recommend this, push the socket into the hole pattern only far
enough to bring the pin tip through on the opposite side. This
will give you room to solder the pin on each side of the board.
In this manner, solder all the IC's (or sockets) in place
according to Figure 1. Be sure that you solder the IC's to the
top side of the board, which is the board having two long wide
segments of plating running parallel to the longer dimension of
the board. Mount and solder - the two 2N2222 transistors in the
places marked in Figure 1. Mount and solder resistors and
capacitors as shown in Figure 2. Most of the resistors are to be
mounted in the vertical, "stand up" position.