Per the attached photo example, I would like to make a copper foil antenna for my 2 meter, VHF ham radio, 36 inches long, and tape it to the inside of the fiberglass cap. Anyone know if there are any metalic elements near the front top center cap of a 1997 U270 that may interfere with the signal?
I like the possibility of drilling no holes, yet be able to talk to my ham radio buddies.
Pretty sure the framework on mine up around there is aluminum.
Clearance lights. They are not all metal but they have metal in them.
Metal frame where the roof meets the walls.
Above and below the clearance lights underneath the vinyl foam lead (I think this what it is) insulation, there is the unfinished fiberglass endcap. The aluminum framing is not in the area where the compound curvature of the endcap. Depending on how much clear space around the antenna, it might work out if you removed the insulation (which is probably very deteriorated and disintegrating anyway.However, there is a fair amount of dismantling necessary to get to that area.
Don
Easy to see the back of the top front cap. Remove all vertical wood trim boards that you see when you open the top front storage space that usually holds video switch, VCR etc. These boards should also be removed to reduce the heat gain in that captive air space.
But you may be better off with an external roof mounted antenna.
We installed a sealed to the roof cable 'combiner' box that has a large inside weather proof access hole through the roof. We attach all antennas with silicon to a large aluminum grounded plate that is firmly attached to the roof. And all antenna and solar power cables enter the coach through the single combiner box.
Do you have a photo of the ground plane / plate and the combiner box? Thanks.
I could not find any roof view photos, but did find the combiner purchase info. Also took a few front photos from below & inside.
Purchased 2011, AM Solar $50 p/n 002-420
I temporarily placed combiner box on roof near front cap seam, marked the about 1"x 3" hole in forward part of box onto the roof, removed box, cut rectangular hole through roof which came out behind front of wood cabinet about a foot curbside from center of motorhome.
Box is screwed to roof, hole siliconed to underside of box.
Combiner box lid is a weather tight cover. I added two more lengths of grounding bus connectors in box.
I drilled holes in side of box to pass antenna cables into box and then down roof hole. Drilled holes siliconed to keep weather out.
Photos show the front edge of the black combiner box. Antennas are attached to the aluminum plate, which is not shown.
The grounding strips carry solar positive and negative connections from each of our six solar panels.
Thanks for the photos. Wow, that's a lot of cooling power for your electronics!
Just regular 12-volt computer fans that turn on with inexpensive home furnace/cooling mechanical thermostat. Gotta keep our entertainers happy and cool. DVR's, SWM-8, Amazon Fire TV, Ethernet switch and power supplies put out some heat. But most heat is from the sun on the front cap, which is insulated from top to bottom and side to side.
We use two similar but larger size fans on inside of refrigerator access door, but turn them on from kitchen only when hot outside. They blow air in and up out the top to keep air moving across the backside of our household electric fridge.
On our coach, Foretravel had installed a cell phone (I assume) booster antenna on the roof above the cockpit. I took that off and just attached a 2 band (2M-440) antenna to the Motorola antenna mount. Don't think there's much if any ground plane up there, but it works fine with my 5W HT or my Yaesu FT-857 and it was easy. If you don't have the center cellphone antenna, maybe replace the CB antenna, if you don't use that?
Nice layout there B&C. And I am really digging the modified Bat'leth painted on the upper front cap.
Yes, one of these options may be a good route. If you have the CB in your coach, but won't be using it, then consider pulling it out and using the space for the 2M radio. The antenna wire and some power is already is already run to that location.
There is a lot of wiring and metal framing in the front cap that could couple/interfere with an exposed foil antenna.
The clearance lights in the front cap receive power from two parallel wires that run the width of the coach inside the front cap from the driver's side to the passenger side. Each light is then tapped into those two parallel wires.
If installing something on the roof, instead of using silicone caulk consider using butyl tape for bedding items (including screws), and a good sealant like 3M 4000UV or Sikaflex. 3M 4000UV can also be used for bedding items.
Eternabond has both single and double sided adhesive tape products that are waterproof and rated for 18-35 years. Their double sided tape would work for attaching a ground plane, antenna mounts, etc. Their single sided tape would work for covering and securing cables, etc. You might need a crowbar to remove the product down the road, but it will stay in place.
3M also make VHB (Very High Bond) tape that would work for attaching a ground plane.
I just removed an antenna install on our rig that was done using silicone caulk. In under a year the silicone was starting to strip and peel away from the antennas. The installer plugged the hole in the roof with the same silicone and it sagged and left a gap around the edges. It was a mess to remove, clean up, and redo in a better fashion.
Chris
(AK4OD)
Tim, re the combiner box you can get a good one from Home depot etc in electric dept that are used for outside connections etc. I use a 6x6x6 box for my roof connections of solar lines and made up my own connection blocks for + and -. Drilled holes in side for weatherproof fittings and away we go. Fasten to roof with VHB tape and caulk.
JohnH
Silicone contaminates gelcoat/fiberglass...just a public service announcement. Google for more info.
I removed the CB antenna, cut the antenna insulation off and converted it to a 1/4 wave 2M ham antenna, 20.1 inches high and put heat shrink tubing over it. The SWR / performance is OK. I will be grounding it to the aluminum cap joint to lower the radiation angle.
I was on the roof today to replace all the cable split loom that was eaten by the UV monster. I tried to buy UV-resistant split loom, but could only find long lengths available, so I used regular split loom again.
While up there I took antenna photos to answer Tim's request. . .
Looks like my Lazy Daze roof did. What my solution was on that was to drill a 1 1/4" hole thru the roof into a cabinet. Sleeved the hole wit a sink tail piece, capped it with an easy to remove RV sewer vent cap. I could then run and remove antenna feeds & wire as I wanted. Kept the tail piece plugged with high density foam that I could remove and replace as needed.
Dave, That is a great idea to run cables from roof to inside, and you could easily add more wires and cables in the future using the same through-the-roof-pipe. That is how we use our combiner box.
But with our center mounted Wineguard Directv antenna, we ran the 4 coax and 1 control cable down fridge vent, then into cabinet next to fridge and then under floor of above-couch cabinets to the SWM-8 located over dash next to DVRs.
I notice you have several cell phone antennas. I guess you have an amp. What do you think is the best combo for 4g? [att]
Thanks, Jim
Jim, We gathered the antennas in one place for ease of mounting, knowing that some of the transmissions would be better served if antennas were further apart.
We have fallen behind on cell boost technology, so now our older Wilson boost amplifiers just handle the older 900 & 1800 mhz bands, but our Verizon 4G is more likely using 700 mhz. So right now, I would say we don't have a working boost.
Only one antenna is cellular. Antennas are dual-band Wilson-Trucker cell, CB, XM-small, XM-tall-marine, FM-radio.
New cellular boost amplifiers and antennas are more legitimate, have to satisfy FCC & carriers, and must not interfere with low-power cell tower signals. And there are many different cell bands being used and new ones coming on the horizon. Some original bands are being dropped. We have no idea what boost to buy. Fortunately Verizon has such good tower coverages, that we often have good voice and data coverage without boosting.
Just think about the cell phones themselves, as they have to be built to connect to the new bands. I figure that new phones can connect to new technology & bands before they are widely available. This business is a moving target, but will benefit us all with faster data speeds. Some new bands probably only handle data, and not voice. Boosts are getting more expensive and usually have limits to what bands they boost. A boost purchase choice today will not be the best choice in a few years.
Cell Phone Signal Boosters: The Definitive Guide (http://www.wilsonamplifiers.com/cell-phone-signal-booster-guide)