My center fed inverted-L doublet is an excellent teacher. First, I'm learning to be patient with #18 AWG stranded copper wire because it loves to kink, bend, and twist. Secondly, I'm learning to deploy my condo contest antenna without an extra set of hands and arms. And, the fiberglass telescoping mast broke earlier this morning -- a 3-foot section failed to lock due to wear at the interlocking joints. However Murphy isn't going to get the best from the problem. Three-hundred mile-an-hour tape or duct tape solves situations like this. More photographs of the center-insulator will follow in the very near future. Last night, I listened on 30-meters and worked Minnesota who reported KA3DRR's receivability, strength, and tone (RST) as 449, not bad for zero sunspot conditions. One will find an insightful article written by L.B. Cebik, W4RNL about the All-Band Doublet. It is especially helpful for entry-level opertors like myself who are on the steep learning curve. Likewise, one can download EZNEC which is an antenna modeling program written by Roy Lewallen, W7EL. His free EZNEC demo program v 5.0 is limited but offers a great opportunity at expanding one's antenna knowledge base and run rudimentary models as well.
73 from the shack.
Cebik, L. B. (2005). 10 Frequency Asked Questions about the All-Band Doublet Retrieved on August 18, 2007 from http://www.cebik.com/wire/abd.html
Lewallen, R. (n.d.). EZNEC Antenna Software by W7EL Retrieved on August 18, 2007 from http://www.eznec.com/.