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eHam Forums => Station Building => Topic started by: N0URE on October 26, 2012, 03:32:58 PM



Title: Watt meter - Antenna Tuner - Who's first?
Post by: N0URE on October 26, 2012, 03:32:58 PM
For the first time I have independent Digital watt meter and auto tuner.
Both LDG. DWM-4 and Z-11Pro II.

Now the questions:
If I put the watt meter first I will read total watts including those lost to heat in the tuner.
If I put the tuner first will it still see the true impedance of the line & antenna or just the front side of the watt meter?
Is the watt meter transparent for impedance to the line and antenna?

John


Title: RE: Watt meter - Antenna Tuner - Who's first?
Post by: KH6AQ on October 26, 2012, 06:47:17 PM
The watt meter is always mounted between the radio and the tuner.


Title: RE: Watt meter - Antenna Tuner - Who's first?
Post by: K1CJS on October 27, 2012, 04:47:17 AM
It really depends on whether you want to see how much power is being delivered to the antenna--or to the tuner.  The wattmeter usually is transparent as far as impedance goes.  If you're going to leave the wattmeter in the circuit, though, yes.  It should be left in between the radio and the tuner.


Title: RE: Watt meter - Antenna Tuner - Who's first?
Post by: WB2WIK on October 27, 2012, 09:29:27 AM
The watt meter is always mounted between the radio and the tuner.
This is the correct answer.

Placing the wattmeter in line between the tuner and the antenna will yield inaccurate readings unless your antenna is well matched to begin with, in which case you don't need the tuner.