You can find more details here : https://f5npv.wordpress.com/w8jk-moxon/
Marc has build this antenna for a while and according the emails echanged with him , find hereafter the details of this tiny antenna . Marc has aslo performed some tests and compare the W8JK with a COBWEB antenna installed in his location.
-He had choosen the “W8JK Moxon style”.
-The Dipoles (Or monopoles) are insulated from the Boom (important , i have tested with dipole connected to the boom and results are poor, many builders had reported the same issue).
-The boom is about 2.70m long
-The fishing poles are 2.50m long only (5m in total)
-Antenna radius is about less than 3 meters (Hexbeam is about 3.3m)
-One of the dipole is 8% longer (I have not tested this variant)
-The feeding is 10% towards the shorter dipole, This will enhance the directivity mostly on the 20m band , and this band will be not bi-directional anymore but providing a backward attenuation. Many builders has choosen this way to feed a W8JK, but myself i choose a feed point on the middle to keep the antenna to be bi-directional on all bands.
For antenna testing , Marc had used a COBWEB antenna installed a the same high . Tests were performed with another amateur radio located about 8Km from Marc Location (Line of sight).
-All band from 20m up to 10m except for the 15m , the difference is about 6dB means about 1 point S-Meter in favor of the W8JK.
-On 15m band , the signal was about 10dB (1.5 S-Meter) in favor of the W8JK.
This W8JK variant is only 2.70m radius which is not usual and can be very useful if you have a limited amount of space . Factually and according all QSO(s) I had achieved with Marc from Brunei (Real QSO using SSB or CW) , it was really peace of cake and easy peasy to contact him . The first QSO(s) we had together , i was using only a long wire antenna.
All QSO with Marc from Brunei (About 11000km) during diffrent propagation contitions:
Many thanks to Marc F6IIV for the feedback and sharing regarding this tiny antenna.
Antenna is an important part of the Amateur radio station. After handling pile-up on different frequencies almost every night for almost 2 years , i can tell you whatever the antenna you have , a beam antenna or even a rotary dipole will make the difference in a pile up . Most of the time , signals from ENDFED , G5RV or dipole are weaker and sometimes by far. Installing just a 2 elements beam antenna (Hexbeam , StepIR, W8JK etc etc ..) will change the perspective of DXing for sure.
For the avoidance of doubt , the W8JK is not a magic antenna , but just an antenna with decent performances and a great radiation pattern. This antenna will be able to fit in a small garding or your apartment roof.
F5NPV - V85NPV 