SWR is calculated by measuring the forward and reverse voltages obtained from T507 and calculating the SWR from those.? It there's no power out then those values can still be measured, they will both be close to zero, with noise.? A 'SWR' value can be calculated but it's just done from two noise measurements which is why the value varies widely.? The power is derived from the forward value only.
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Chris. G5CTH
