LF: Re: Vintage RF current meter

[Rik Strobbe <rik.strobbe@fys.kuleuven.be>]

Hello Luis,

 

one way to change the range without opening meter is to use two 4/1 radio transformers:

- first transformer high side to the TX, and low side to one and of the meter

- second transformer low side to the other end of the meter and high side to the antenna

Drawback: the transformers will introduce some additional loss

 

  -----                  -----

       }|    Meter     |{

       }|     +--+     |{       

TX     }| ----|  |---- |{       Antenna

       }|{    +--+    }|{

  -----   ------------   -----

 

73, Rik  ON7YD - OR7T

 

PS: drawing needs a monospace font (eg. Courier New)

 

---

Van: owner-rsgb_lf_group@blacksheep.org <owner-rsgb_lf_group@blacksheep.org> namens VIGILANT Luis Fernández <luis@vigilant.es>
Verzonden: woensdag 4 mei 2016 10:46
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: LF: Vintage RF current meter

 

Hi xyF

 

Yesterday I got a nice gift from a local friend, Pascual EA5JF :-)

 

https://dl.dropboxusercontent.com/u/7162072/Fotos%20varias/MF/IMG_20160504_091006.jpg

 

Unfortunately the current range under 1A looks unusable 

Still not opened to have a look. Seems to use a thermocouple. Is there any chance to make it

more sensible and usable for <1A currents ?

 

73 de Luis

EA5DOM