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Ah, yes...... preparing the radio for eBay: "one slightly used Cobra 142GTL with all the modifications and 'funny' channels. Never mobile. Tech Special. Needs microphone cord."

Looks GREAT! Nice job making the shelf high enough to put even even the largest transceiver below it, and strong enough to hold the boatanchor(s), amp(s), or whatever other goodies you have instore.

Don't know if this antenna is still in production, but look up the Anttron 1600 or 1600s; it's basically like a 'Half-Breed', it's about 6 feet long, center loaded, with the bottom 2 feet in fiberglass and the top 4' as a very FLEXIBLE stainless steel whip. It's long enough for efficiency, and...

Inverted Vertical with only 2 Radials Take a dipole antenna about 16' long, and add an 8 1/2' vertical radiator to it (just dangling down and floating in the breeze, or you can tie it off to the ground.) Feed it at the TOP, with your center conductor going to the vertical radiator, and your...

The Old Reliable 1/2 Wave HORIZONTAL Dipole Up to this point we have been investigating VERTICALLY POLARIZED antenna patterns. Now it's time to share a secret with you.......... A vertical antenna does NOT obtain "gain" from ground reflection, merely ground LOSSES. We run vertical on CB...

The 'Mysterious' Sigma IV, Vector 4000, etc. Demystified Let me start off by saying: "Don't be a HATER"... I do indeed realize that there are several of you in this forum who absolutely adore this engineering marvel, and I do indeed respect and admire the performance of this antenna. This...

3/4 Wavelength Monopole In the model below, please find the 3/4 Wavelength Monopole (a beast approximately 27-30 feet in length) fed against four (4) 1/4 wave horizontal ground radials. Again, the feedpoint is at 20 feet above real ground. Picture 1 shows the antenna RF currents Picture 2...

The .64 Wavelength Vertical Radiator Okay, so does a .64 wave radiator really outperform a 5/8 wave antenna? If so, then WHY do all the so called antenna 'Gurus' out there claim that the maximum gain figure for a monopole element is at 5/8 wave? The answer lies in the fact that there is...

5/8 Vertical with Four (4) 5/8 Wavelength Radials Okay, this antenna is LARGE. The vertical radiator will be 21 - 24 feet in length, and each of the four radials will be the same length as the vertical element (21-24 feet each). But, does it work? I'd have to say that since it only...

5/8 Wave Vertical with Sloping Radials The model below shows what would happen if you sloped your 1/4 wave radials on a 5/8 wave vertical. The TOA does NOT drop (like it did on the Starduster vs. 1/4 wave Vert), BUT the gain DOES increase somewhat, and the sloping radials will certainly help...

The 5/8 Wave Omnidirectional Verticals The 5/8 wave vertical I am modeling here is 21 feet in length, and incorporates four (4) 1/4 wavelength horizontal radials. Picture 1 shows the antenna and it's maximum current flows Picture 2 shows that maximum gain (at a 20' feedpoint over real...

STARDUSTER (M-400 & derivatives) Model To make a 1/4 wave vertical perform better (i.e., lower TOA, better match to 50 ohm coax, less likelihood of common mode currents on the outside <shield> of your coax), we slope the radials downward to achieve the following model: 1 Shows the currents on...

Well, the XYL didn't have any "Honey-Do's" for me this Labor Day weekend, so I figured I'd take a few moments and model some of our favorite CB Antennas. Please note that I am using EZNEC DEMO VERSION, which limits me to only 20 segments, therefore all antennas were modeled at 20' above REAL...

I wonder WHY everybody keeps calling this antenna a J-POLE? I thought the ASTROPLANE was a J-POLE and the Sigma IV is merely a gamma-matched 3/4 (7/8) wavelength monopole with the inverted cone to decouple the coax to prevent the shield (braid) from radiating???