Hi Gary, Yes, I noticed the advert said -20dB coupling which would equate to 10 turns, but the 7V DC for 100W did not match, it would be closer to 10V and there looked to be more than 10 turns on the example shown. Provided the turns ratios match on both sides, Scott should be able to calibrate the bridge with a known power source/meter.
It seemed a bit odd that 50 Ohms was fitted on the FWD side (100//100) and 51 Ohms on the REV side. I assume it is to reduce the FWD resistor power dissipation under normal low SWR conditions, although the PCB would allow for 100//100 on both sides.
