LED SWR BRIDGE FOR QRP PORTABLE OPERATIONS
Captains Log , star date 08032014, Act 1 Scene 1
I finally got around to some bench time and managed to build my LED SWR Bridge for Portable Operations.
WHY!
1.) Well its smaller and lighter to carry around in a Go Bag .
2.) I don't fancy the idea of using my AV-601 SWR meter in the field and risk damaging or scratching the instrument in the field.
3.) Its a great feeling home brewing my own ham radio gear and using in the field.
4.) I need to be able to check that my MFJ Antenna Matching Box has in fact matched to my Long Wire Antenna , with as little as possible VSWR on my feed line.
THE DESIGN
Criteria : Simple easy to use lite weight
The design used was gathered from information on the internet.
A Hand Drawn Schematic
Components used were as follows:
3 x 50 Ohm 15 watt 1% Thick Film Resistors
1 x 10 Kohm Resistor 1/4 watt 5 %
1 x 1N4148 Signal Resistor
1 x High Bright (Blue) LED Clear Plastic
2 x 0.01uf Capacitors Ceramic
1 x Toggle Switch
Some PCB Board to make up an RF Shielded Box
Picture Taken From Top Showing UGLY Style Construction
Tune /Operate Toggle Switch
Transmitter Side Connection SO239 (Going to Output of RIG)
Antenna Side Connection SO239 (Going to Antenna or MFJ Box)
How does it work , one word "GREAT" , so far i have tested on 40 meter band as well as 20 meter band and i can get the LED to extinguish nicely , indicating a match.
Now to try it in the field and see if i can see the LED in sunlight and see how it performs on a portable setup.
