Tennadyne T6 LPDA

In October 2010 I replaced my old Fritzel FB-33 tribander (20/15/10m) trap Yagi with a Tennadyne T6 6-element LPDA (Log Periodic Dipole Array) which now works very well and offers no-tune coverage continously from 14 to 30 MHz. The antenna resides 15 meters above ground level on the top section of a Versa-Tower which is mounted on top of an unused chimney. This chimney contains a reinforcing steel tube and is filled with concrete all the way down to the basement of our house. However, a lot of work had to be done before I could take this picture from an attic window ...



After dismantling the old antenna, I cleaned and re-painted the top-section, installed the new antenna rotator Create RC5A-3 with the UC-1 universal coupler plate, the CK-46 mast bearing and the stainless-steel supporting mast assembly. The result is shown on this picture. Note the tiltable joint in the mast assemby - it plays a vital role since it allows final assembly of the partially assembled antenna on the roof.



A close-up view of the rotator and coupler plate. The tower top-section is welded to a 1" thick steel-plate covering the chimney.



Emirates Airline brough my T6 from Toledo / USA to Frankfurt / Germany. After inventory of all antenna parts on the basement floor ...



... I pre-assembled the four boom-sections with only the two inner sections of each element ...



.. and brought these four pre-assemblies up to the balcony to put them together - this is the result.



Now this assembly was mounted on the supporting mast ...



... and subsequent tilt-and-rotate allowed me - standing between the chimney and the roof - to reach the pre-assembled section ends in order to install more and more tubing sections.



The T6 comes with nothing but two holes and screws to attach coax at the feedpoint, a solution which is not good at all ! So I constructed this weatherproof feedpoint-assembly with sliding hood from aluminium stock, PCB material, an SO-239 connector, stainless-steel hardware and grey perspex.



This balun-assembly was constructed in the same fashion - the balun is a common-mode choke made of 7 turns of RG-58 coax on two stacked Amidon FT140-43 toroid cores.



The feedpoint-assembly with hood, installed at the boom end with the shortest element ...



... and the balun-assembly still without hood, installed at the boom-mast insulator. Except for the balun windings Aircell-7 coax is used.



All elements, the feedpoint-assembly, the balun-assemby and the shorting stub at the boom-end with the longest element are installed now.



This is my plasic crow named "Karl-Theodor" (after Germany's former defence minister Karl-Theodor zu Guttenberg) - he defends the T6 against pigeons and 8 months after the installation I can say that he does an outstanding job, since I have never seen any pigeon sitting on the antenna ;>)



A view over my hometown Pforzheim, standing on the chimney below the T6 heading North.



... mission completed !



This is the roof of our house with the Tennadyne T6 LPDA installed on the chimney and the Titanex V40 vertical on the balcony. My radio shack is the corner-room behind the steps with a door to the balcony.