||07-18-2007 12:00 AM
Relax - a quality 48" whip vs. a 48" firestik; the whip will outperform hands down.
If you look at a firestik you'll notice it's basically a fiberglass rod with some copper wire wrapped around it at spacing that varies. The higher you go up the antenna - the closer the windings get. This results in an impedance increase as you go up the antenna physically (decrease electrically as it's a top load antenna); impedance being the resistance to electrical change (in this case RF). What this means is that only a select portion of the firestik is physically used in effectively transmitting.
Why the impedance ramp? It results in easier tuning across a broad range in frequency - very usefull when you have such a short antenna for such a long wavelength (11 meters - a 5/8 or 1/2 wave antenna would be 5.5 meters or so, a 4' firestik is barely over 1) which makes tuning a challenge.
Compare this to a standard whip on top of an impedance matching coil (we'll ignore the 102" whips in this case). This system relies on the natural impedance of a metal length of wire to be adapted through a series of windings in order to match the 50 ohm load most transmitters expect to see for the peak power output. This means once this is achieved - the WHOLE length of antenna is used to radiate RF energy, instead of only a small portion of the antenna being used in a significant way. Downside? They're a bit more specific in where they are considered 'tuned' as they are tuned to a very specific frequency.
Creating impedance matching coils is no easy feat either however. IMO a cheap radioshack whip deal with a half ass coil will lose to a marginal antenna such as the Firestik, however get something decent (which there is quiet a bit out there), and you'll have a pretty significant upper hand.
I do run a firestik... why? I got it for free, and even if not it's a cheap antenna - which is important to me since I don't really care about my CB setup as long as it works on the trail [I have a ham setup for anything more demanding]. However FireStiks are a LONG throw from a quality antenna if that's what you're wondering.