Gudmundur wrote:
If I know only the power in dbm is there a formula to arrive at
vswr without conversion first to watts or volts?

outbound = +63dbm (2kw)
reflected = +36dbm (4w)


Take the formula for calculating vswr from P in watts, previously converting
the dBm into W.
You'll get the following vswr=(1+10^(0.5*(Pout-Pref)))/(1-10^(0.5*(Pout-Pref))).


Regards,
Pawe³ Stobiñski, SQ9NRY