[Elecraft] powermeter

[Fred Townsend]

Ross, not to put too fine a point on it, but a power meter and a SWL meter are not the same. Without a directional coupler a power meter will read both forward and reflected power making readings appear overly high with high SWR. A power meter, i.e. watt meter will only be accurate when terminated into a 50 ohm resistive load.

Now assuming you are using a directional coupler with two signals, the tuning process lowers return power so it should located between the amp and the tuner, usually at the amp end of the coax.

73
Fred, AE6QL

-----Original Message-----
>From: Ross Biggar <rbiggar at ihug.co.nz>
>Sent: May 12, 2015 4:06 PM
>To: elecraft at mailman.qth.net
>Subject: [Elecraft] powermeter
>
>This is probably a very naive question, but where should a powermeter that measures Forward and reflected power
>be positioned?
>Should it be between the Amplifier and the Tuner, which could safeguard the amplifier if there was a high SWR,
>or after the tuner, (ie, between the tuner and the antenna)?
>
>Thanks
>Ross ZL1WN
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