Barrie, an easy way out is to use an RF ammeter in one of the legs of open
wire line and simply tune for maximum RF current. If you're running a KW,
you'll probably need a 0-10 A meter.
73, Joe
barrie99@marsweb.com wrote:
> Hello:
>
> I'm building a 160M only link-coupled antenna tuner. Will have a Bird
> wattmeter on the input side, but would like to have a "relative power
> output" indicator on the output side (600 ohm balanced line).
>
> I've seen schematics for such devices in handbooks, but they are used on
> the output of amplifiers running into 50 ohm loads, and include
> provisions to measure reflected power, as well.
>
> I'm thinking that the voltage on the 600 ohm line could be much higher
> than it would be on 50 ohm line.
>
> All I (think) I need is a voltage dropping resistor, a diode, a pot to
> fine-tune the voltage and a DC meter. I just don't know the values of
> each.
>
> Anyone know where such a circuit may be found?
>
> TNX, Barrie, W7ALW
>
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