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I need an antenna that will get me on the channels above 27.3. My Galaxy
goes to 32 mhz. Simply shorten your coax 2.01734695436248538129 feet. An even easier method for achieving a similar result is to simply modify the coax cable a bit, so as to change the dielectric constant of a small length of the cable's internal insulation. This generates an impedance "bump" which acts as a short matching section, tuning out the higher SWR which results if you try to "push" an antenna beyond its normal resonant frequency range. The DC can best be modified by displacing a small amount of the insulation to the side. Simply measure back along the cable from the antenna approximately 1/4 electrical wavelength, and then drive a small nail straight through the center of the coax - it must penetrate the center conductor, and (ideally) the braid/shield on both sides of the cable. Typically, a 1-penny nail is of the correct length and diameter. For small-diameter cable, try a carpet tack. Test the freeband transmitter's SWR and see how well it transmits. You might find it necessary to adjust the cable at several points, a few inches on either side of the quarter-wave-away-from-the-antenna point to get the best match. I have not actually tested this procedure with a Galaxy radio - your results may differ, and (as with any homebrew electronics or antenna modifications) they're done entirely at your own risk. -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
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