Active on AO-40 from the very beginning, i use mostly 70 cm uplink with 50-60W on a 18 els crossed yagi,but i have made several qso´s with the 23cm uplink.

I found that i was able to hear myself at the noise level with a power as low as 2 Watts in a 15 elements yagi (yes!) , and with 40 meters of small heliax !

Increasing to 5 W gave a readable signal, and 10 W gave a S-3.

Note that the downlink is a 3 meters dish , with a modified AIDC 3733 converter.(crystal+filter+stub).The converter is directly fixed on the feed,and the probe soldered in place of the original dipole.

I have built two helix antennas for portable operation, but had no time yet to try them:

I now you can see nothing, my camera is just a toy :-)

For the groundplane reflectors, i used backelite PCB .It is much easier to solder the connectors on it. Then i cut a 15mm thick plastic disc,bolted with one 8mm srew in the center.The screw will serve for the fixing of the antenna.The PVC tube that holds the wire is srewed in the thickness of the plastic disc , in 5 places .The 6th one can´t be intalled because of the connector.

Click HERE to see construction hints for a 13cm feed with adjustable F/D.

 

 

 

 

 

 

 

 

 

 

 

 

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