Technical post.
Wavelength=234/frequency in megahertz
Assumption: antenna broke for your GMRS FRS radio.
Tools: wire cutters, needle nosed pliers, measurement tool. (All are found on a Leatherman ® tool)
Parts: wire (electric fence wire, home electrical wire, coat hanger, barbed wire, etc) a SO-239 Antenna connector (female).
Given the GMRS FRS service shares some of the same frequencies we will need to know where those frequencies are. Channels 1-7 and 15-22 all are found between 462.550 and 462.725Mhz. going for the middle of those we find the frequency of 462.637
Plug that into the formula. 234/462.637 and you get a measurement in feet.
.5057 or just over 6 inches. (15.4cm)
Cut your a section of wire to this length or slightly longer. Next we'll cut the radials. They are 12% longer so 17.25cm but we'll cut them even longer for this Antenna. Cut four 7in sections.
Assembly: place the 6in section into the center of the so-239 connector. Using a lighter (unless you have access to a soldering iron in the woods) heat the wire and connector and solder them together. Note: solder flows to the heat.
Once completed, attach the radials by placing 1/2 inch of the radial through the chassis mounting holes and crimp them to the so-239. Soldering is preferred here to ensure good electrical connections.
Angle the radials to approximately 45° down this increases the impedance from 35 ohms to 50 ohms for coaxial matching. Hang the Antenna and make contact
This is NOT my design.
Note for the above: channels 8-14 are 467mhz FRS channels and so are the GMRS repeater inputs. You can RECEIVE ONLY on these channels. To avoid damaging the radio beyond a broken Antenna DO NOT TRANSMIT on channels 8-14.
Good solid antenna build. Good job! One of the easiest to make and fairly effective...way better than no antenna!
Kind of makes me want to make my own antenna for my GMRS radio. Great information.
That's the idea... I mean sure, the best fix for a broken antenna is not breaking it in the first place. Second is purchasing a factory replacement and simply swapping the broken antenna out, and third is something you can make out of procure on site materials.