Antenna Mounting
The attractive molded housings are easily removable for installation or adjustment. Simply remove the two silver-color screws located at the rear of each housing and gently pull the housing forward, away from the black metal rear plate (Fig. B).
For portable or temporary use, install the included AT8667 brackets with BNC connectors and 5/8"-27 threaded mounts. Attach each bracket to an antenna using two small, black machine screws (included). Direct the screws from inside the antenna’s rear plate through the inner pair of small holes, and screw them into the tapped holes in the bracket. Prepare the free ends of the short cables as shown in Figure C.
For permanent installation, the antennas may be attached to a wall or other vertical support with appropriate fasteners. They also may be mounted to a single-gang electrical box, via the outer pair of small holes on the rear plate (using #6-32 screws, not included). When installing, position the units so the gain switches and screw terminals face to the right.
The PC board may be removed for safety or convenience while installing the metal rear plate, if desired. Simply remove the two screws indicated in Figure B. When re-mounting the PC board, note that the board goes on the “outside” of the rear plate’s mounting ears.
Fig. B
Antenna | Power | |
Housing | Indicator | Rear Plate |
| | PC |
| Center | Board |
| Mounting |
| Conductor |
| Screws |
| Lo Mid Hi | Cable |
| Clamp |
| |
| Gain | Cable Clamp |
| Housing Screw Switch | Screw Locations |
Internal Connections
Cable Selection
Screw-terminal connections in the antennas are designed for use with RG58-type or RG8-type RF transmission cables, or with Asian RF cable types 3D or 5D. Make certain the cable selected is intended for UHF operation and has a full braided copper shield, not just a metalized foil shield. For runs of 25' (8 m) or more, a low-loss cable such as RG8 should be used.
Cable Stripping
RG58: Observing the dimensions in Figure C, remove a section of the outer jacket and a portion of the inner coax insulation, being careful not to cut or nick the shield or center wires (C1).
Note: If the cable jacket’s outer diameter is less than 7/32" (0.21", 5.3 mm), wrap the jacket with electrical tape to build up its diameter before folding back the braid over the jacket (C2). Trim the shield wires to 9/16" (15 mm).
RG8: When using RG8-type cable, more jacket material needs to be removed and partially replaced with shrink tubing. When installing the tubing, heat the tubing and cable only enough to shrink the tubing. Allow the cable to cool fully before manipu- lating it further. The drawings in Figures D and E are actual- size; the shrink-tubing indications show the actual length of pieces to be cut, and their correct placement on the cable. Cut the required pieces from the included shrink tubing.
RG8 / Rear exit: When connecting antennas from the rear, fol- low the cable-stripping dimensions in Figure D. Then install a 1"- long (25 mm) piece of shrink tubing as indicated. Remove the cable clamp and carefully insert the cable end into position through the rear plate.
RG8 / Bottom exit: When connecting antennas through the opening in the antenna housing, follow the cable-stripping dimensions in Figure E. Then install a 2.5"-long (63 mm) piece of shrink tubing as indicated. Remove the cable clamp and carefully position the cable to exit at the bottom edge of the rear plate. The end of the cable’s jacket must be located about 1/4" (6 mm) beyond the end of the rear plate to clear the bottom of the housing. Then secure the clamp and center conductor.
