My child’s dream came trough

Since I was young I have ever dreamed on the day that I could talk to distance places with a tiny radio and antenna on my hand.

On October 29, 2004 when I was complaining 54 I could realize my dream.

The radio is a nine AA battery operated 10/11 meters AM/FM/SSB handy talkie coupled to the base of a small magnetic loop by the belt clip.

This type of 10/11 meters AM/FM/SSB radios was sold in great quantities with brand names like Cherokee AH 100, Titan RPSY 1020, Magnum 1010, Dragon, etc.


I have two versions of these magnetic loops that can be attached to the belt clip of the radio.

The smaller is my very first one made with coaxial cable and a 3 / 30 PF capacitor covering between 24MHz to 60 MHz. The tuning on 10 meters and 12 meters is a little tight.

The second one is made with soft cooper 6 MMS tube.

On this loop I decide to use a low capacitance split capacitor and a small piece of coaxial cable to be paralleled to the variable capacitor acting as a parasitic capacitor. This solution allows the frequency to be adjusted between 25 MHz with the capacitor closed to 30 MHz when the capacitor is completely open resulting on a smooth frequency adjustment.

Another problems is the absent of a SWR meter, that I compensate making a miniature pick up coil connected to a germanium diode, a tape recorder VU meter and a 50 K small potentiometer near the top of the antenna sensing the RF energy on a AM transmission. In other words a FSM (field strength meter) is always living on the antenna.

On the cooper tube antenna, I have I adapted a plastic cylinder inserted on the antenna wood boom to adjust the view angle of the FSM with the radio on the upright position.

My first DX was to the North Brazil region, after that I have made contacts to Slovenia, Argentina, Russia from shopping centers parking, on walks and on my condo balcony surrounded by buildings.

PY1 AHD ALEX (Alexandre Grimberg).

e-mail: py1ahd@ig.com.br