Installing a Rohn 45 Tower requires proper planning, attention to safety, and following detailed steps. When done correctly, this sturdy tower provides reliable support for antennas used in amateur radio, broadcasting, or communication networks. Here’s how to complete the process, from digging the hole to mounting the antenna.
Step 1: Planning and Preparation
Start by choosing a suitable location for the tower. Ensure the site is free from overhead power lines and has enough space to accommodate the tower and guy wires. Check local regulations and secure any necessary permits. To avoid complications later, mark underground utilities by contacting your local utility service.
Step 2: Digging the Hole
Mark the tower’s base dimensions as specified in the Rohn 45 installation guide. Then, dig a hole that matches the required depth and width, typically around 4 to 6 feet deep, depending on your soil conditions. Use a post hole digger or rent a small excavator for precise digging. Afterward, clean the hole of loose soil to ensure a stable foundation.
Rebar Install in Hole
Proper rebar installation is crucial for the stability and longevity of a Rohn 45 tower footing. Reinforcing the concrete with rebar ensures the foundation can withstand the tower’s weight and environmental stresses. Here’s how to install the rebar effectively.
A: Gather Materials and Tools
Start by gathering the required rebar, typically specified in the Rohn 45 tower installation guide. You’ll also need tools like a rebar cutter, bender, and wire ties. Ensure you have the correct rebar diameter and lengths, as well as spacers to maintain proper positioning within the concrete.
B: Lay Out the Rebar Grid
Begin by laying out a rebar grid that matches the base dimensions of the tower footing. Use the tower’s anchor bolts as reference points to position the grid correctly. Cut and bend the rebar as needed to fit the design specifications. Ensure that the rebar extends to the edges of the footing while maintaining a clearance from the soil to prevent corrosion.
C: Tie the Rebar
Once you’ve positioned the rebar, tie the intersecting pieces securely with tie wire. For added strength, make sure the ties are tight and evenly spaced across the grid. Additionally, double-check that the rebar sections are not loose, as this can compromise the integrity of the footing.
D: Position the Rebar in the Hole
Before placing the grid into the hole, attach rebar spacers to maintain proper concrete coverage. Carefully lower the grid into the hole, ensuring it sits evenly. If the design requires vertical rebar for additional reinforcement, tie these pieces to the horizontal grid before placing it in the hole.
E: Check Alignment and Clearance
After placing the rebar, confirm that it aligns with the tower’s base section and anchor bolts. Use a level or measuring tape to verify consistent spacing and clearances. Proper alignment at this stage ensures a secure connection between the tower and its foundation.
F: Secure the Tower Base to the Rebar
Attach the tower’s base section or anchor bolts to the rebar grid according to the manufacturer’s instructions. Use clamps or ties to hold the base securely to the rebar structure. This step creates a strong bond between the tower and the footing once the concrete is poured.
Step 3: Pouring the Concrete
Assemble the base section of the tower, including rebar reinforcements if required. Position the tower base into the hole, ensuring it remains level and properly aligned. Order the concrete according to the manufacturer’s recommendations(usually 4500 psi) and pour it into the hole. Smooth the surface and let the concrete cure for at least 7 days, although longer curing improves stability. I like it to cure 7 days for every 20 foot of tower, for example, a 60 foot tower would need 21 days to cure.
Step 4: Assembling and Raising the Tower
Attach the subsequent tower sections to the base, securing each section with bolts. Use a gin pole and a pulley system to lift sections safely. Tighten the bolts as you add each segment, ensuring alignment. At this stage, install guy wire anchors around the tower base at the recommended distances.
Step 5: Securing the Tower
Once the tower reaches its full height, attach the guy wires to the anchors. Tension each wire evenly to keep the tower stable and upright. Adjustments may be necessary to ensure the tower remains perfectly vertical.
Step 6: Installing the Antenna
Before mounting the antenna, verify that all bolts and guy wires are secure. Raise the antenna by pulling it up, using a gin pole, or a trolley cable system. Check the SWR then attach the antenna to the tower’s top using a mast or mounting brackets. Run the coaxial cable along the tower and secure it with stand offs, clamps, UV-resistant cable ties, or just let it hang. Lastly, make sure to leave enough at top for rotor movement. Ensure proper grounding for the antenna and the tower to protect against lightning.
Step 7: Final Checks
Inspect the entire installation for stability and compliance with local codes. Test the antenna’s performance to confirm proper alignment and functionality. Finally, maintain a clear area around the tower to prevent damage or interference.
Installing a Rohn 45 antenna tower involves precise steps and careful attention to detail. By planning thoroughly, securing the foundation, and ensuring proper alignment, you can create a durable setup that supports your communication needs for years to come.