Re: Does QCX Mini have DIY emission indication function? #qcxmini


Arv Evans <arvid.evans@...>
 

If connecting a resistor and a diode to output of your transmitter, you
should probably put the resistor between the transmitter output.  This
provides isolation and neatly steps around the ancient myth of diodes
in SWR bridges and RF voltmeters causing harmonics.

There is also the possibility of using a single transistor or mosfet
amplifier to increase output of the diode detector.

Arv
_._


On Thu, Mar 18, 2021 at 9:57 AM <jakob@...> wrote:
Interesting! Are you sure the diodes are 1N4148? I will experiment with this circuit to find out how the led current is generated. Whatever it is, it is most likely a non-linear circuit and induces harmonics, as every non-linear component does in RF. But not a problem if applied before the LPF. BTW, what band is this QCX Mini?

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