Week 7

Another week down, transmission lines, antennae, and propagation were on the menu this week. The differences between a balanced feeder , (like open wire feeder, 300 and 450 ohm ribbon) and an unbalanced feeder (coaxial cable), the electromagnetic characteristics of each (and the facilitators preference).
Dipoles, horizontal, vertical, folded, 1/2 a dipole (a vertical antenna with a groundplane as the other side), as well as yagi and log periodic antennae were all discussed, feedpoints, that dreaded SWR, baluns and antenna tuning units.
One little nugget I gleaned, in respect to an OCF dipole (off centre fed) is where you feed it makes a big difference. Basically it is a windom and is traditionally fed 1/3 from one end. The disadvantage of this is that the antenna will not work very well at the 3rd harmonic of it's designed frequency. So an 3.5Mhz antenna fed at 1/3 will be a poor performer on 10.5Mhz etc.... We can't have that. It was suggested that feeding it at 1/5 will take the "useless" frequency about 18Mhz, and I can't use that one anyway. The beauty of wire antenna is that if it does not work, pull it down and build another one!!
Next week recievers!!

On the way home, I had a chat to a fellow amateur about the callsign issue, and he made a few suggestions. VK7LVM is a possibility or another linux based one. I really should have used VK7FSCK for my foundation call, but I was too overcome from passing to really think the callsign bit through.

Anyone reading this, please think of a witty 3 letter suffix, in the range of:
VK7Haa, VK7Laa, VK7Maa, VK7Paa, VK7Vaa, substituting the letters for aa. And VK7HAM is already gone!