QRP L Match With SWR Bridge

So with the new year comes new projects, I am not going to set out what my overall plans and goals are as I have started way to many things and never bothered to see them through or to complete them. So with that in mind, I am building a L match

Its hard to make out, but you can just see the LED glowing, the signal is 10v p-p from the signal generator, the load is a decade resistance box. At infinite swr there is 1/2 the p-p voltage at the junction of the rectifier and capacitor. As swr approaches 1:1 the voltage drops to a point where the LED turns off. Its simple and its a winner.

It will get paired up with the sotabeams switched inductor and a 8-370pf air capacitor. as an L match. Should be good enough for the kinds of girls i go out with. Below is the schematic I am following for this project and a link to the authors site is at the bottom of the page. In the final build I will use 3w 50ohm resistors and the diode i used was a Schottky, i don’t recall the numbers it was just something i had in the parts box, I used the Schottky for its lower voltage drop, though that is probably not all that critical seeing that LED’s are current limited, not voltage.

Link to authors blog post: HERE



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