Construction Info for a W6TED loop

The loop is built in a small shielded box made out of PC Board material.  
The Box measures 1.0" x 1.75" x 2.0" and the sides and front are assembled using 
solder beads on the inside surfaces.

4 ea .75" spacers are mounted in the corners of the front panel using 4-40 Pan head screws. 
The back panel is also attached with 4-40 Pan head screws.

Male and Female BNC connectors and a loop support bracket are mounted on the outside of the box.  
The tuning capacitor is mounted to the center of the front panel.  
It should NOT be grounded to the box!

The loop is formed, using 1/4" copper tubing, with a Spring Type tubing bender.  
The inside Diameter is not critical, and should be in the 2 to 2.5" range. 
An oval access hole is made at the bottom of the loop opposite the GAP to 
allow the inner wire to exit.

Attach a small support bracket at this point using solder.
The unit should be wired as shown in the schematic. Try various
STUBBY rubber ducks and use the one with the best pattern. 

Adjust the capacitor for MAX signal with the Sense Antenna removed!
Then, with the Sense antenna connected, the signal should peak  with the 
signal source facing you.  If it has a NULL in front of you swap the wires going to the loop.  
This will rotate the Cardoid pattern 180 degrees.  The optional 2k POT can be adjusted 
for best pattern.

The capacitor I used was actually a 4 section unit from my JUNK Box.
It is the type commonly used in transistor radios.  I use 2 sections in series to reduce 
the total capacitance to approximately 15 pf. 

The capacitor also provides a convenient mount for the coil.
My loop tuned from 120 to 160 MHZ but this will be dependent on the capacitor tuning range 
and the actual loop size.

The only thing unique in this design is the use of a parallel inductor (L2) to REDUCE 
the effective inductance of the loop (L1) itself.  
This allows tuning to the two meter band with a common value capacitor range!

I hope you find this to be a helpful addition to your T-Hunt bag of tricks!  
I would also like to get some feedback on your success and any modifications you 
may like to suggest.


	Please contact me at - - - >  w6ted@sbcglobal.net


	73's  Bruce (W6TED)