Often I receive emails from people asking for the dimensions of the HF2V elements because they want to build one themselves. Well, here are the dimensions for all the coils and capacitors. Good luck with your experiments! Continue reading “Do it yourself HF2V”
Category: Antennas
Articles and blogs about antennas. Both commercial off the shelf antennas as well as home made DIY experiments by Alexandru Csete OZ9AEC.
HF2V on the Air
As you can see on my HF2V pictures, my HF2V is mounted in between a lot of trees. There is even electric fence only 10 meters from it. Nevertheless, it performs very well both on the RX and TX side. It has also been standing for more than a year now and can cope well with the winds on the Danish west coast.
Lucky DX, again…
I don’t know how it happens, but very often I find myselv being on the right frequency at the right time. The right time means when a DX station starts calling but before the crowd begins shouting.
Pile-Up on Me
Finally, an evening without any significant QRN on 40! I was doing pretty well, working UA9O, UN9, 4L1, when suddenly there started to be a small pile-up on me.
Listen Twice as much as You Speak
I am sure there are many biological reason why a human has two ears and only one mouth. However, some poeple chose to interpret this fact as humans are supposed to listen twice as much then they are speaking.
Tuning the Butternut HF2V
Like with any other multi-band vertical the different bands are coupled with each other. This means that modifying the settings on one band will influence the others. This effect is worst on the low bands (40 and below) and less noticeable on the higher bands. If you only have the basic two-band HF2V there are only two bands/parameters to adjust and you can easily get through the alignment by doing a few iterations on each band. However, if you have the 30 or the 160 (or both) extensions mounted, aligning all 3 or 4 bands can become an endless process.
My HF2V is now OTA!
Now that my HF2V was tuned rather well, it was time to test it on the air.
I started out on 30 meters where I worked SVØXAO right away. He gave me 589 and I gave him 599. Despite the good reports there was a lots of QRN on the band. This didn’t stop me and the HF2V to work VO1TK who was using an IC-735 and a dipole. Not bad.
Later on I worked many more contacts, including TU2 and VP5 on 40, and OY3 and CN2 on 80. The HF2V is doing very well!
New Strategy for HF2V Tuning
Tuning the 80 meter coil of the HF2V messed up my settings on 40 and 30 meters in a way that I ended up with barely acceptable SWR on all 3 bands. I definitely needed a new tuning strategy.
Tuning the 80m Coil
Now it’s time to adjust the 80 meter coil. The current setting for all three bands are given below
Tuning the 40m Coil
With the current settings on 30m (26cm 2.5 turns shorted), fc on 40 shifted to 7.188 MHz – even with 8 turns shorted. Moving the shorting strap to 7 turns, fc shifts to 6.988 MHz. With 7.5 turns shorted fc = 7.039 MHz.