View Full Version : RV Bonding

Off Pavement
04-08-2012, 07:12 AM

I'm in the process of installing a Tarheel H100 screwdriver antenna on a motorized lift mounted to the ladder on our 25' class C. I'd say this is an experiment of trying to get a pretty good compromise of mobile and portable RV ops with a single antenna.

I've got my mount secured, and I've decided where all wires and cables will run. After spending days over at KBG.com (http://k0bg.com), it quickly becomes apparent that bonding is perhaps the most important aspect of antenna implementation for any mobile application. If you read Allen's web page, he stated it took him 8 hours to bond his Honda Ridgeline. Having a uni-body vehicle made his bonding even easier according to his comments.

My RV on the other has hand has virtually no bonding, so yesterday I spent the afternoon getting started. I have a steel bumper with decorative aluminum riveted to it, so I bonded the aluminum sheeting, bumper, lower portion of the antenna lifter, and hitch to the frame. I've bonded the aluminum coach frame and a bolted frame cross member but there are more cross members to bond.

I can hardly wait to start bonding the generator and support hardware. Everything is bolted and needs bonding. I haven't even started to think about the hood, doors, cab body and engine compartment yet, but I will say that self drilling screws are your friend! It takes me longer to make the bonding straps than it does to install them by far.

I admit that I'm anxious to try out this configuration and will probably hook up the radio and see what happens with the bonding I've done so far. I'm pretty sure it will work at least to some degree until I start the engine or generator, but I guess I'll just have to give it a whirl...

04-08-2012, 11:22 AM
Welcome Brian and thanks for sharing your project with us. Several pictures would be nice.
Sounds like you like the work of the project rather than the hamming at the end.
Why not try using the radio before all that additional bonding is complete. You already may have gone far enough.
The pictures would help understand your objective.
You mention mounting on the ladder and bonding the antenna lifter. Does the antenna get lifted when you are parked? If so you don't have to worry about your engine.
Much bonding can be accomplished with strips of solid metal, copper/aluminum, not as much prep as braid and better if there is no movement between the members being bonded, just snip it off the sheet/roll and drill/screw it into place.

Wondering are you setting up mobile or portable. I only operate when parked.

JIM :bag:

04-08-2012, 03:51 PM
Question for Brian...

What are you using for bonding straps?

Off Pavement
04-08-2012, 08:13 PM
Jim... I don't really anticipate operating mobile but I suppose it could happen as long as my XYL is doing the driving at the time. I just can't imagine pounding brass and driving, though I've run across several mobile CW ops that do. Actually, I do enjoy the construction portion of this project and I am patient. I'm working on a write-up of this project so once I get it complete, I'll let you know. My objective is have a decent performing antenna system on our RV that can be raised and lowered easily without needing to get up on the roof for deployment.

Radio... I'm using tubular tinned copper braided wire soldered to lug terminals screwed into the frame.

04-09-2012, 01:28 PM
My class A will be easier -- it's nearly all wood and fiberglass, so there's little to bond other than the frame itself. I'm considering various screwdrivers, leaning toward the KJ7U versions. Currently using a vertical dipole consisting of the ladder (lower half of the dipole) and a stainless whip (upper half of the dipole). The ladder isn't grounded, so it works as the lower half, and I feed with coax at the top of the ladder, which is the bottom of the whip. All running from an Icom IC7000 and LDG IT-100 tuner, which will tune it everywhere from 6 meters to 40 meters.

Unfortunately, though it tunes, no one hears me. Gotta do something better.

Off Pavement
04-17-2012, 02:18 PM
I will get some pictures of the screwdriver antenna lifter and mount posted in a couple days, but so far performance has been good! 1st QSO was from near Cozad, NE to FL with the second getting me a 599 from Poland.

I have not tried 80 meters yet though it did load fine. I've had QSO's on 40, 30, 20, and 15. I haven't found 10 open yet. My operating location is pretty lousy with a brick 3 story building right next to me so shadowing should be a concern, but I've worked stations between me and that building.

One minor issue came up with my initial tune up on 20 while hooked to shore power... I showed nearly flat SWR on 20 at 5w during antenna adjustment, went to 100w and the air conditioner started to sound like it was trying to start. I tripped the breaker for the AC and problem solved. Cut the shore power, reset the AC breaker and no problem. I didn't try it again on any other bands, but I'm thinking some beads are in my future.

For my first shot at portable ops, I'm a pretty happy camper! :bounce:

06-18-2012, 08:03 AM
Here is a really good article about screw driver antennas and matching. K0BG.com/match.html