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Old October 18th 05, 09:42 PM
John - KD5YI
 
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Default power formula for vswr?

Paweł Stobiński wrote:
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,
Paweł Stobiński, SQ9NRY



SWR = -1?