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160m mini portable End Fed Half Wave Tuner - MkII.
A small portable 160m EFHW tuner design.

This is the mini version of the previous version. The air core inductor is replaced with a toroid and the variable capacitor is replaced with a fixed capacitor combination.
 
 
160m EFHW testing
 
 
Schematic

The schematic of what I've used. The capacitor is a fixed value because little tuning is required. The antenna can be further tuned by altering the length of the antenna. UPDATE:Practical field tests verified this - that altering the line length of the antenna (shortened by 2 metres in one instance) a vswr of 1:1 could be achieved.

 
 
160m mini EFHW tuner testing
 
 
Put in a box.

Here's a photo of the bits in a box being tested.

 
 
160m mini EFHW tuner testing
 
 
Field testing.

What better way to test this set up than to conduct the 160m VK5 WIA callback on a Sunday morning! Not bad, considering the kite only came down once during the callback, went back up and stayed there. Low power and portable. Great day on the beach, too.
The photo below shows the tuner connected in series with the broadcast reject filter feeding the radio using 50 ohm coax. The glove is for handling the kite wire!
 
 
160m mini tuner in use.
 
 
Finished project.

The final project with label. Another project completed. Just the thing to do, on rainy days ....
 
 
160m mini tuner - finished.
 
 
Portable kit.

Most of what is seen here, is placed in the backpack (not shown) for the radio, with the exception of the kite (stored in it's own bag), the wire and spool assembly and fold-up seat (not shown), which are carried by hand.
 
 
160m & 40m Portable kit.
 
 
Summary:

The setup for 160m and 40m using an end fed half wave tuner and a kite is simple and easy to setup. The results prove that good signal reports can be had using a half wavelength antenna with minimal grounding.
 
       
    2006 - 2009 S.Spirat 
Another SPIRAT initiative