For those using a calculator with a square root function on it - the 0.35355 is the sq.rt. of 2 divided by 4. I find that one easier to remember than a seemingly arbitrary conversion factor. Each to his own as they say. 73, Don W3FPR ----- Original Message ----- > Direct conversion from pk-pk to rms voltage: > > Vrms = Vpp x 0.35355 (ARRL 1998 Handbook conversion factor, page 6.6)