May 10, 2007

It is not quite finished yet but this is a prototype 3 element yagi antenna for Jupiter radio astronomy work.  
This particular antenna is for 18.7 MHz.  The boom is 20 feet long made from 2 lengths of 3/4" black pipe.
The elements are made from bamboo fishing poles which hold insulated copper wire ( lamp cord )  taped to the bamboo.
The driven element connects to 75 ohm coax.  It is connected to a Sangean ATS-803A radio inside
the observatory.

Director element :  23' 8-13/16 "
Driven element per side:  12' -7 3/8 "
Reflector element:   26'  8-21/32"
Spacing :  9' 11-13/16"

(In the background left part of the above picture is my regular Jupiter antenna which is a Hy-Gain tribander for 14, 21, 28 MHz.)





I am trying first to get by without a "beta match" for this antenna.



Due to super high mountain winds I have the back of the antenna tethered to a weight on the ground. ( Weight is out of the picture.)

The antenna receives the rise of the galactic center SagA*  but I am still waiting for Jupiter to emit at 18.7 MHz for proof and "first light."

Here is a link to my other Jupiter work and sound files.
Jupiter_Pulse_&_Power

Thomas Ashcraft
New Mexico
ashcraft(at)heliotown.com


.