I have finished the PCB layout for the SWR meter. The SWR meter circuit is given again below for reference Click for full sized image. The circuit consists of two identical channels. The forward voltage channel is J1 to log amp U3 to voltage follower U1A. The corresponding reverse voltage channel is J2 to U2 to U1B. A regulated 5V supply is provided by U4.
The diagram below shows the KiCad circuit board layout for the circuit, looking from the top of the board. Red traces are top copper, and blue traces are bottom, which is mostly the ground plane.
The Vf and Vr signals come in on SMA connectors at the left edge of the board. The log amps U2 and U3 are SOIC surface mount devices. The buffer amps are in the dual DIP package U1. The output signals for Vf and Vr go out J5 and J6 respectively. I used through hole inductors L1 and L2 for isolating the DC supply from the log amps. DC signals are sent off board using 0.1" headers J3, J4, and J5. All the capacitors and resistors are 0603 SMD parts. These 0603 parts may turn out to be too small to handle. I still have not tried practice soldering of these parts.
The figure below shows the KiCad generated 3D image of the board. I really love the 3D image feature of KiCad, it's very helpful for sizing board size before ordering. You can plainly see the rf coax inputs on the left, the going right the log amps U2 and U3, the dual buffer amp U1, and finally the measured forward and reverse signals coming out the headers on the right edge of the board.
The board was ordered from PCBWAY on April 14. After clearing up a question about solder mask on one part (my mistake), the sent me a note that the board had been completed and shipped. For low cost I elected for USPS shipping. I believe the board should arrive sometime the first week of May. I have two more PCBs to order: 1) the control board for the Philmore 12V supply, and the NE602 direct conversion receiver.
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