All you need to build a simple VHF or UHF 1/4 wave groundplane antenna is a coax chassis connector and number 12 or larger wire scraps. Solder the vertical element to the center conductor and attach the radials with nuts and bolts to the four corners, then solder each corner. Make the vertical element a bit longer than calculated and bend the radials down 25 to 30 degrees a short distance from the connector flang