Here are just a few tips on what to do when assembling a new antenna. The suggestions hold true for both vertical and horizontal antennas.
This is a basic information Tech Tip. The information and tips listed here were compiled while working with top antenna builders/installers. This list is not a do-all, know-all list, and other items can and should be added as needed.
First and foremost: SAFETY is always number one. Be sure to wear the proper safety gear. This includes a hard hat, gloves, and safety glasses. Make sure you are not near any power lines. Stay at least 10 feet away from them.
Order your antenna ahead of time
- Do not wait until the week before you plan to install it.
- It may take time to get the antenna from the dealer. Supply shortages and delivery times have become longer due to multiple reasons.
- You do not want your antenna arriving the day before a scheduled installation—especially if helpers are involved.
When the antenna arrives
- Do not just put it aside to begin assembly the day before installation. Open the box and inspect the antenna parts for any possible damage done during shipping.
- Also, check the parts list and ensure everything is present. This gives you time to contact your dealer in case parts are needed to get things ready for assembly.
Ensure you have the proper tools and supplies for the assembly of the antenna
- Maybe you need metric wrenches and/or a socket set?
- Have Jet-Lube SS-30 for both the mechanical parts and the elements on hand. You may want some rubber/nitrate gloves and rags. SS-30 will not wash out of clothes.
- Have a good supply of 3M Scotch 88 tape.
- Have a roll of Temflex 2155 Rubber Splicing Tape for your coaxial cable connection.
- Get the proper tape measure (might need metric).
- Get a few work stands or “horses” to use for assembly. Trying to assemble an antenna on the ground is not very comfortable and can cause assembly problems.
- Do you have your coaxial cable and/or the proper coaxial connection device (if needed) for your antenna?
- Are there any additional clamps or hardware needed for a proper and safe installation?
- Use small boxes or tubs to put the loose hardware in so small parts will not get lost when assembly starts.
- When attaching elements, use a level—it helps ensure all the elements are in-line with each other.
Start the assembly
- READ the manual that comes with the antenna. Then, read it again.
- Check the Dealer and/or Manufacturer’s website to make sure you have the latest revision of the manual.
- The manual may also point out what tools and additional items are needed.
- Ensure you know the proper sequence to be followed for proper assembly.
- Use a good electrical/RF conductive grease between all elements and also use it for all the hardware to ensure the stainless steel hardware will not gall. Jet-Lube SS-30 is the suggested compound to use for this purpose. The use of Jet-Lube SS-30 is recommended by more than one Contest Super Station for all antenna construction.
- If assembly is going to be in the yard, lay down a large tarp under the work stands. This will make it easier to find nuts, bolts, and washers that may be accidently dropped during the assembly.
- For a Yagi antenna with a round boom, use U-Bolt clamps to hold the boom on to the work stands. You will drill holes in your work stands for the U-Clamps. This does a couple of things. It holds the boom steady. And, when attaching elements and using a level, it helps ensure all the elements are in-line with each other.
- Follow each step in the manual. Re-read each step a couple of times to ensure you understand and complete each step in the assembly properly.
- Double check element spacing and lengths. Triple checking is good, too.
- Do not use end caps on the Yagi elements. You want to leave a path for moisture to drain out. Yes, insects and bugs can get in, but eventually they die and decompose. Any buildup of condensation will help flush that material out of the element. If you plug the ends with caps or other objects, you are blocking the water’s escape route. Winter temperatures will freeze the built-up liquid and split the element tubing open.
- Boom end caps must be modified with a hole at a low point to allow moisture buildup to drain away.
- When attaching your coaxial cable, ensure the connector is tight. Waterproof the connector using Temflex with an overwrap of Scotch 88 tape.
- One installer interviewed for this Tech Tip also recommends using Scotch 88 around the junction points of the elements.
- If the antenna is outdoors, temporarily protect the other end of the coax cable from any moisture. Using an empty plastic water bottle over the coax connector and then wrapping with tape to hold it in place will help ensure this.
Once the assembly is complete
- Go back and ensure all bolts, screws, clamps, etc. are properly tightened.
- Let the antenna sit for a day or two. Go back and check every bolt, nut, and clamp again to ensure they are tight.
- Verify SWR measurements by temporarily raising the antenna to help ensure that all is properly assembled. Be aware that at ground level, the SWR will be a bit higher as compared to the installation height SWR measurement.
Installation on your mast
- SAFETY is always number one. Be sure to wear the proper safety gear.
- Make sure you are not near any power lines. Stay at least 10 feet away from them.
- Follow all proper safety precautions to ensure no one is accidently injured during installation.
- All people helping should be wearing a hard hat in case something drops while on the tower or roof or wherever you are installing the antenna.
- Ensure you have an adequate number of helpers to ensure a safe installation.
- Again, double check what the manual recommends for mounting the antenna to your mast.
- When mounted, it is recommended the coaxial cable be positioned to allow water to drip off and not run toward your antenna connection point. This is called a “drip loop.”
- Additionally, use Scotch 88 tape to secure the coaxial cable to your mast (or tower leg) every three feet or so. Do not use cable-ties or zip-ties; they can pinch the coaxial cable when tightened and eventually cause problems with your feed line.
Once installed, verify proper SWR measurements again. Then get on the air and have fun with your new antenna.
Routine maintenance should be done every year. Follow the recommendations of the antenna manufacturer. Also, inspect coax cables.
Note: To reiterate, SAFETY is the Number One Priority—The user MUST be familiar with, understand, and follow all recommended or mandatory safety and installation instructions that are available or supplied by the original manufacturers of the materials/parts listed in this Tech Tip. DX Engineering is not responsible for any damages or injuries as a result of using this Tech Tip.
This article is based on information from multiple conversations with Tim Duffy, K3LR, DX Engineering CEO, and Tim Jellison, W3YQ, longtime ham, experienced and credentialed tower climber, certified rescue technician, and qualified climbing instructor.
