C2,
That piece of RG-174 coax is used as a 1/4 wave phasing section on 440. At 145 Mhz it acts just like a plain piece of wire, but at 440 Mhz it acts as a timing or phasing section to make the 17" above and below it into a two section vertical array. Nothing wrong with doing that, but I have 'qualms' about using RG-174 for anything (just a personal thingy, not very important).
- 'Doc
How about this one?