CB 27 Glass Mount CB Antenna (210-0985) Preparation Faxback Doc. # 33100 TUNING THE ANTENNA For the best performance, tune the antenna using an SWR meter. Follow the SWR meter's instructions to connect it to your CB and the antenna cable. To adjust the SWR, turn the tuning capacitor in the coupler box using the supplied plastic tuning tool. NOTE: A very small change in the tuning capacitor's setting can make a big difference in SWR. Tune the antenna in very small increments. If you cannot get an acceptable SWR, clip the supplied ground wire to the metal collar on the coupler, then secure the other end to a metal vehicle part. If the supplied wire is not long enough, attach another wire between the supplied wire and a metal vehicle part, but keep the additional wire as short as possible. (YO/EB 5/14/96)