Circularly polarized fm broadcast antenna 1 to 4-bay, full-wave-spaced (50 pages)
Summary of Contents for Shively Labs 6822
Page 1
Circularly Polarized FM Broadcast Antenna Model 6822 Instruction Manual Installation, Operation, & Maintenance...
Page 2
Congratulations! Thank you for purchasing one of the finest FM broadcast antennas on the market today. The Shively Labs 6822 is the top-of-the-line in its class for its simplicity, superior performance and durability. Your purchase is backed by the best technical support in the industry. Shively is a leading manufacturer in the broadcast industry, providing an extensive range of antennas, transmission line and components.
Page 3
IMPORTANT Please read this manual in its entirety before beginning installation of your antenna! Failure to follow the installation and operation instructions in this manual could lead to failure of your equipment and might even void your warranty!
Table of Contents Chapter 1 Preparation ................ 1 Check the shipment................1 Torque specifications................1 Table 1 Torque specifications ............. 1 Check the parts..................1 Set up the mounting location..............1 Tower-leg mount................2 Support-pipe mount................2 Top-mounted support pipe..............2 Preparing the tower leg or mounting pipe ..........
Page 6
Table of Contents Install the slugged line section (if applicable)........24 Figure 19 Slugged line section installation (if applicable)..... 25 Install the optional fine-matching transformer (if applicable) ....26 Figure 20 Fine-matching transformer installation......27 Connect the antenna bay cables............28 Figure 21 Antenna bay cable connection ........
Page 7
Bay components (without de-icers) ............57 Table 5 Components, antenna bay without de-icer (per bay) ..57 Figure 42 Components, 6822 bay (without de-icers)....58 De-Icer Components ................59 Table 6 Components, de-icer (per bay) ........59 Figure 43 Components, 6822 de-icer......... 59 Mounting system components ..............
Page 8
Table of Contents Table 12 Components, feed system for 4-bay antenna (per array) ..............65 Table 13 Components, feed system for 5-bay antenna (per array) ..............65 Table 14 Components, feed system for 6-bay antenna (per array) ..............65 Table 15 Components, feed system for 8-bay antenna ...
Improper antenna mount- ate unwanted electrical signals, and performance may be degraded. ing is a leading cause of CAUTION poor performance in 6822 Watch for tower components that might interfere with your installation. antennas. It is very Mounting is a little different for tower-leg mounting, support-pipe mount, and important to install the top-mounted poles.
Preparation Tower-leg mount The 6822 antenna may be mounted on a tower leg if the tower has at least 18" face width. The width is necessary to allow separation between the antenna and the power divider, as shown in Figure The tower leg must extend at least five feet (1500 mm) above the top bay and five feet below the bottom bay.
Preparation Figure 3. Tower layout, two-bay antenna IMPORTANT! If you ordered a custom- spaced antenna, please refer to your antenna test data sheet for bay- to-bay spacing.
Preparation Figure 4. Tower layout, three- bay antenna IMPORTANT! If you ordered a custom- spaced antenna, please refer to your antenna test data sheet for bay- to-bay spacing.
Preparation Figure 5. Tower layout, four-bay antenna IMPORTANT! If you ordered a custom- spaced antenna, please refer to your antenna test data sheet for bay- to-bay spacing.
Preparation Figure 6. Tower layout, five-bay antenna IMPORTANT! If you ordered a custom- spaced antenna, please refer to your antenna test data sheet for bay- to-bay spacing.
Preparation Figure 7. Tower layout, six-bay antenna IMPORTANT! If you ordered a custom- spaced antenna, please refer to your antenna test data sheet for bay- to-bay spacing.
Preparation Figure 8. Tower layout, eight- bay antenna IMPORTANT! If you ordered a custom- spaced antenna, please refer to your antenna test data sheet for bay- to-bay spacing.
Bay Assembly Bay Assembly Attach the mount to the bay weldment Mounting pipe size to 3-1/2 NOTE For mounting pipes between 3-1/2" and 6" diameter, see the next sec- inches outside diameter: tion. NOTE The mount is reversible and can be attached to either side of the bay weldment.
Bay Assembly Figure 11. Mount attachment, pipe size up to 3-1/2 inches Table 2. Mounting U-bolt usage Mounting pipe size U-bolt size Up to 2 inches (5.1 cm) 2 in (6.35 cm) outside diameter 2 to 4 in (5 to 10.2 cm) 4 in (10.2 cm) 4 to 6 in (10 to 15.2 cm) Figure 12...
Bay Assembly Figure 12. Mount attachment, pipe size 3-1/2" to 6" Attach the bay arms. CAUTION Do not loosen the hose clamps or move the sliding V-arms. This will spoil the performance of your antenna. a. Locate the inner and outer dipole arms (Figure 13, 7).
Bay Assembly Figure 13. Bay arm attachment Attach the bay cable NOTE If your antenna has more than one bay, skip this section and go on to (single-bay antenna Attach the feedstraps to the endseal. only) a. Attach the angled connector of the bay cable section (Figure 14 on page 17, 8) to the base of the endseal (9).
Page 25
Bay Assembly Figure 14. Bay cable & feedstrap attachment (bay cable for single-bay antenna only) d. Tighten the feedstrap clip hardware, only until the lock washer flattens. Do not overtighten.
Mounting the Antenna Bay(s) Mounting the Antenna Bay(s) WARNING Whenever a rigger is on the tower in the area of the antenna, shut off the signal and lock it off so that it cannot be turned on accidentally. RF emissions at close range are hazardous. CAUTION Do not attach the bays together with the RF cable before mounting them.
Repaint the pipe as needed around the antenna bay mount. Figure 16. Bay mounting on pipe 3-1/2" - 6" OD NOTE The Model 6822 does not require pressurization or purging. The feed system up to the bay may be pressurized. Proceed to Connecting the Antenna (single-bay)
NOTE The Model 6822 bay does not require pressurization or purging. Installation of your Model 6822 single-bay is now complete. Please proceed to Startup on page 51.
Connecting the Antenna (2- to 6-bay) Connecting the Antenna (2- to 6-bay) Mount the power Using a power divider mounting kit (Figure 18, 45), mount the power divider (46, 49, 52, 55, or 58) to the mounting structure with its outlet ports roughly divider.
Connecting the Antenna (2- to 6-bay) Install the slugged line In the event your antenna has non-standard bay spacing or other special fea- tures, we may have provided you with a line section containing a "slug" to section (if applicable). perfect the tuning of the antenna.
Connecting the Antenna (2- to 6-bay) Install the optional One of the unique features of Shively Labs antenna systems is the adjustable impedance-matching transformer (Figure or 73, as applicable) option- fine-matching ally available with the antenna. It allows the installer to compensate for...
Connecting the Antenna (2- to 6-bay) Connect the antenna CAUTION Stressing a coax connection after assembly can detune the system. bay cables. Therefore, never make a connection and then bend or twist the cable, or use the connector to force the coax into shape. Form the cable first, then attach it to the connector.
Connecting the Antenna (2- to 6-bay) Connect the tower a. The antenna system is not pressurized, but the tower transmission line may be. If necessary, provide a gas stop between the tower transmission line and transmission line. the system input (power divider input, or transformer input if applicable). b.
Page 38
NOTE The Model 6822 antenna does not require pressurization or purging. The feed system up to the power divider may be pressurized. Installation of your Model 6822 2- to 8-bay antenna is now complete. Please proceed to Startup on page 51.
Connecting the Antenna (8-bay) Connecting the Antenna (8-bay) Mount the power a. Using two mount bases (Figure 23, 63), two saddles (64), and two hose clamps (65), mount the 1-5/8" 2-way power divider (62) onto the mounting dividers. structure with its outlet end roughly halfway between bays 4 and 5. Locate the mounts as close to the ends of the power divider as you can.
Connecting the Antenna (8-bay) Install the optional One of the unique features of Shively Labs antenna systems is the adjustable impedance-matching transformer (Figure 25, 73) optionally available with the fine-matching antenna. It allows the installer to compensate for changes in the input imped- transformer (if ance caused by the installation (tower, conduit, ladder, etc.).
Connecting the Antenna (8-bay) Connect the antenna CAUTION Stressing a coax connection after assembly can detune the system. bay cables. Therefore, never make a connection and then bend or twist the cable, or use the connector to force the coax into shape. Form the cable first, then attach it to the connector.
NOTE The Model 6822 antenna does not require pressurization or purging. The feed system up to the power divider may be pressurized. Installation of your Model 6822 2- to 8-bay is now complete. Please proceed Startup on page 51.
Remember that conditions may be favorable for icing on the tower, even if they are not on the ground. Shively Labs deicers are designed to prevent ice from forming on antenna ele- ments and are not designed to melt ice that has already formed. For this rea-...
Installing the De-icer System (if applicable) Table 3. De-icer specifications (continued) Heater leg Heater leg (T1 or T2) current draw, amps resistance, 8-Bay, single circuit De-icer installation Installing the de-icer a. Insert the electrical leads (Figure 28, 23) from the antenna mast through the side port of the junction box.
Installing the De-icer System (if applicable) Figure 29. Junction box installed on antenna bay NOTE The access cover of the junction box may be positioned on the left or right side. c. (Top bay only) Using PTFE tape to seal the opening, install the pipe plug (Figure 28, 26) in the top port of the junction box.
Installing the De-icer System (if applicable) Figure 31. Sheath cut back (3) Slide the grommet to the end of the insulation. Unravel the sheath as necessary and bend it back over the grommet (Figure 32). Figure 32. Sheath bent back over the grommet (4) Insert the leads through the body and the top port of the second junction box.
Installing the De-icer System (if applicable) Figure 34. De-icer electrical schematic diagram NOTE Customer-supplied items are shown in broken lines. NOTE Wire nuts, cover with screws, and gaskets, and tie-wraps provided with the de-icer cable sec- tions. CAUTION Shively Labs's de-icer control box, Model 94068, is designed for interior...
Installing the De-icer System (if applicable) f. Inside each junction box, connect the leads as shown in Figure 28, using wire nuts (7) to secure the connections. g. Repeat for the remaining bays, junction boxes, and interbay cables. h. Secure the interbay cables to the mounting pipe or tower leg, using tie- wraps.
To test and adjust VSWR safely, use low-power test equipment, such as a network analyzer. If you don't have access to low-power test equip- ment, please call Shively Labs before proceeding. WARNING Whenever a rigger is on the tower in the area of the antenna, shut off the transmitter signal and lock and tag it out so that it cannot be turned on accidentally.
Retuning Tuning Figure 35. Arm length vs. frequency Figure 36. Feed strap angle vs. frequency a. Tweak for minimum VSWR from there (see Chapter 9). The specification is less than 1.2:1 (Figure Figure 38, and Figure 39).
To test and adjust VSWR safely, use low-power test equipment, such as a network analyzer. If you don't have access to low-power test equip- ment, please call Shively Labs before proceeding. WARNING Whenever a rigger is on the tower in the area of the antenna, shut off the transmitter signal and lock and tag it out so that it cannot be turned on accidentally.
VSWR for each frequency at this point should be below 1.2 : 1. If it is not, call Shively Labs to help identify the problem. g. When you have set the transformer, use a sharp point to scribe the shaft of each control rod where it leaves the flange collar.
Take initial readings, and repeat the readings periodically. c. Performance readings should not change, and there should be no evidence of abnormal heating in the antenna system. d. If any problem is found, fix it now. Call Shively Labs if you need help or advice. Operation.
Maintenance Maintenance WARNING Whenever a rigger is on the tower in the area of the antenna, shut off the signal and lock it off so that it cannot be turned on accidentally. RF emissions at close range are hazardous. We recommend that you keep a log of VSWR readings and any other perfor- mance notes and maintenance history for your antenna.
Parts Parts NOTE Item numbers are consistent across all the illustrations in this technical manual, with the exception of the assembly drawings in Appendix A. Bay components Table 5. Components, antenna bay without de-icer (per bay) (without de-icers) Part Number Description Qty.
Parts Mounting system components Up to 3-1/2" mounting NOTE For mounting pipes between 3-1/2" and 6" diameter, see the next sec- pipe OD: tion. Table 7. Components, mounts for up to 3-1/2" mounting pipe (per antenna bay) Part Number Description Qty.
Parts 3-1/2" - 6" mounting pipe NOTE For mounting pipes up to 4" diameter, see the previous section. Table 8. Components, mounts for 3-1/2" to 6" mounting pipe (per antenna bay) Part Number Description Qty. 36. 98141-06 Mount, balun for 3-1/2" - 6-5/8" OD 1.
Parts Feed system Table 9. Components, feed system for single-bay antenna components Part Number Description Qty. 42. 82912-G506 Kit, flange hardware, 7/8" flange 43. 9068-215 O-ring, silicone, 7/8" EIA flange 44. TY529MX Tie-wrap Table 10. Components, feed system for 2-bay antenna (per array) Part Number Description...
Parts Figure 46. Feed system components for 2- to 6-bay antennas...
Page 73
Parts Table 12. Components, feed system for 4-bay antenna (per array) Part Number Description Qty. 45. 98162-G501 Kit, power divider mount, 7/8" & 1-5/8" 52. 158F-716X4 Power divider, 4-way 1-5/8" EIA flange to 7/16 DIN male 53. 82912-G501 • Kit, flange hardware, 1-5/8" flange 54.
Page 74
Parts Table 14. Components, feed system for 6-bay antenna (per array) (continued) Part Number Description Qty. 60. 97353-G505- (Half-wave-spaced) Coax cable section, 18 216.00 ft (5.49 m) long, 7/16 DIN male on input end and 90° 7/16 DIN male on output end 44.
Parts Accessories and Table 16. Accessories and optional items optional items Part Number Description Qty. 70. Various Line section, slugged, 7/8" 42. 82912-G506 • Kit, flange hardware, 7/8" flange 43. 9068-215 • O-ring, silicone, 7/8" EIA flange 71. Various Line section, slugged, 1-5/8" 54.
Need help?
Do you have a question about the 6822 and is the answer not in the manual?
Questions and answers