I didn’t realize vehicle bonding could be so much fun and I learned a few lessons along the way. My Icom IC-7000 has been in my vehicle for the past year, ever since I got the Icom IC-7300 for the shack. I did a little vehicle bonding a long time ago, but not good enough for the Tarheel 200A that is mounted on the rear of my 2006 Hummer H3. It’s a large mobile screwdriver antenna, see the video.
The Tarheel 200A is an outstanding mobile screwdriver antenna for HF and to get the most out of it I needed to do some proper vehicle bonding. Most of you have probably already read the articles on vehicle bonding from other Hams or from the Tarheel website, so I won’t bore you. It’s a lot to take in.
What I will mention are the tools and parts used, because I searched long and hard trying to find some good ones that matched up. See the parts list at the bottom of this article.
Braided Grounding Strap: I used a 3/4″ copper braided grounding strap since I had it on hand. It’s tinned copper and comes in 10 ft lengths. You can also get 1″ copper braid too. Not a bad price on either!
Lugs: I bought Gardner Bender® Xtreme 6 AWG Steel Heavy-Duty Lugs at Menards and later found similar one’s on Amazon for a much better price. However, they are not as heavy as the Gardner Bender from Menards and will require a washer on top. They are 6 AWG marine grade copper lugs. The 3/4″ grounding straps are a snug fit. The 1″ may not fit , but you can always get a larger lug if you want.
Lesson #1: Not all lugs are created equal.
Screws: The screws came from Menards and they are stainless 14 x 3/4 HEX self-drilling with washer. You can find similar one’s on Amazon or your local hardware store. The vehicle steel thickness will determine if this screw is suitable for your vehicle. I was drilling through “medium” thickness steel.
Lesson #2: The screws I got from Menards are high quality and came with a neoprene EPDM bonded sealing washer. I used the washer, but in the future I will use serrated lock washers.
Misc: Although probably not necessary, I used some electrical tape on the lugs and then some liquid tape to fill it in. For a professional job I should have used heat shrink tubing. I’ve used liquid tape on cable before and it’s okay, but heat shrink tubing is the best.
Lesson #3: Someday I should invest in a heat gun.
Tools: Electric drill, drill bit, cable cutter or tin snip, hammer, screwdriver, blow torch and solder.
Lesson #4: Buy a good bit and drill slow into steel, the bit cuts better.
Here’s my vehicle bonding video:
The Icom IC-7000 is fantastic mobile rig and I love operating mobile or portable with it. The little bonding I’ve done has made a noticeable difference in engine noise, especially the brakes. It was the exhaust grounding that fixed that. The Hummer H3 has electronic brakes and I used to hear noise in the radio everytime I applied the brakes. Not any more!
I still have a lot more to do like bonding the body to the frame and I’m trying to figure out a place to put a bonding strap on the front doors and the rear door. It’s tricky.
Updates on this project to come.
After shooting the video clip I ran another bonding strap from the Tarheel hitch bolt to the receiver (see above, strap to the left).
This is not meant to be a definitive guide on how to properly bond a vehicle. For that see K0BG.com.
In the past I have received some great ideas from other Hams, so if you have any comments, questions or suggestions, please feel free to comment below. How did you do your vehicle bonding and did it help?
Thanks and best 73 – Rich, K0PIR
Vehicle Bonding PARTS LIST: