Saturday, January 8, 2011

Roof Antennas

There are a number of different types of antennas to be found on the roofs of RVs. The two standard ones that come with a Lazy Daze are the AM/FM radio antenna and the crank-up Winegard TV antenna. Other antennas include those for CB radios, cell phones, satellite TV dishes and even short-wave radio.
AM/FM Antenna
There's not much to be said about this antenna. It's installed by the factory with a hidden cable terminating behind the dashboard, where it plugs into the radio. It's mounting includes a swivel fitting so the antenna can be laid flat on the roof should you want to put a cover on your LD.

If you should somehow damage or lose this antenna, you can replace it with the mast portion of a Metra Universal Rubber Antenna available at most auto parts stores for about $10. It's a perfect fit down to the retaining screw and diameter of the split-ball swivel base.
TV Antenna
This is the ubiquitous Winegard crank-up antenna found on virtually any RV with a TV. It's controlled by an interior ceiling-mounted crank which is used to crank the antenna from a flat-on-the-roof position for travel to an upright position for TV viewing.
Caution: More than one of these antennas has been damaged or even worse, ripped off the roof, when the driver left camp without ensuring that the antenna was down. It's a great idea to use some sort of reminder such as a clothes pin: when the antenna is stowed for travel, put the clothes pin on the crank handle; when the antenna is up, clip the clothes pin to the gear shift lever.
Some basic preventive maintenance is needed to keep your antenna working. Basically it consists of lubricating the crank mechanism on the roof with some silicone spray. See the owner's guide for complete details.
Should you neglect the lubrication, you may find it difficult, if not impossible to, rotate the antenna. One possible fix is to get some PB Blaster (a penetrant), soak the mechanism really well and wait over night. It should be free the next day.
Crank won't work? Check for broken shear pin. Check for loose set screw and tighten as necessary. Check the worm gear and crank handle. If replacing the handle, be careful when buying it; you can purchase the white handle to fit either the round worm gear pole, or the hexagon pole. The beige only comes with the round. Both will fit, but the round handle will dig into the aluminum hexagon pole after a while and strip it. The handle can be purchased from PPL or other RV suppliers. You can see the two models here: PPL Crank handle
CB Antenna
If your LD came with a factory-installed CB radio, it of course also includes an antenna, with hidden cabling down to the radio.
If you install a CB radio yourself, you'll have to mount an antenna for it. The LD with its aluminum roof creates a situation in which a normal CB antenna that you might mount on your car roof, either with a magnetic base or a permanent mount, will not work, since there is no steel to provide the necessary ground-plane. This can be resolved by using a special non-ground-plane antenna such as those manufactured by Firestik.
To hold the antenna, aluminum brackets can be glued to the roof with the proper epoxies. All surfaces need to be bare and wire brushed or sanded. Use an etching solution on the surfaces to be bonded and then glue. I use West Systems epoxy and aluminum etching solution. Make the brackets large enough to provide plenty of bonding surface area. Paint the area when finished.
For best operation, you'll want to use an SWR meter to "tune" your antenna to your radio. The Firestik antenna has a bolt on its top, under a vinyl cap, that one turns very slight in or out, depending on the readings on the SWR meter.

Having trouble tuning your antenna? Check for poor connections. Here's what one RV'er discovered:

I unbolted the antenna assembly from the roof and hidden within the caulking (sealing putty) was a small connector that the screw that holds the antenna assembly down went through. That connector was nearly completely covered with caulking, so it was not making a good, or any, contact. I scraped all the caulking off the connector, and off the bottom of the plate that holds the antenna to the roof. That connector goes to the metal ground plate that is somewhere under the roof. I then re-screwed the antenna assembly back to the roof and checked the SWR. I could not believe the results. After some very minor adjustments I have 1:5 on channel 1:1 on 19 and 1.6: on 40.

A great source of information on CB radios and antennas can be found at Right Channel Radios.
Cell Phone Antenna
Through-the-glass antennas: Most folks agree that these are of dubious value. While this *could* be an improvement over the little antenna built into the cell phone, it's nothing compared to the improvement to be had with a directly-connected outside antenna. The rooftop is the best place for any antenna, but for a small cell phone antenna that doesn't present much of a wind load, you could also consider putting a hole through a side wall up near the roof line, and using a right-angle side-mount antenna. As long as most of the antenna extends up over the roof line, you shouldn't see much of a directional effect from the LD house. The bed area over the cab would be one possible site, or inside one of the overhead cabinets ifyou wanted to hide the hole on the inside. The same sealing caveats noted in another response would apply to a hole through the side.

Most RV'ers use the Wilson Truckers/RV antenna, which provides a major improvement in cell reception, which can be magnified even more by using a cellular amplifier with the antenna. The antenna can be permanently mounted on the roof in several ways, either in a hole drilled through the roof, or on a bracket or luggage rail.
There is a problem with a permanent vertical mounting, however: near the top of the nearly 3-foot antenna are 6 small ground plane rods. They are VERY fragile, easily broken off by a low-hanging tree branch. Thus it pays to get a little inventive and devise a way to mount the antenna so it can be easily stowed in a lowered position to reduce the chance of damage to the rods.
One method is to use a marine-type railing clamp, mounting it on a luggage rail near the ladder. You can then step partway up the ladder and with a flick of the wrist, you can position the antenna for either use or travel.

Another approach is to mount the cell antenna on the crank-up TV antenna mast. Now you won't even to go outside to stow or raise the antenna. When you lower the TV antenna, the cell antenna also come down to an almost horizontal position, keeping the ground plane rods a few inches above the roof. I've had mine mounted like this for several years and have yet to break a rod.

If you really like to be out in the boonies, you might want to consider the installation of a directional yagi antenna on a telescoping mast.

For any antenna you add to the roof, you'll have to get creative in getting the cables inside the rig. Various entry possibilities include an LD-installed roof cable vent, the bathroom vent stack, or the refrigerator vent. And of course, if you're brave, you can drill holes - just be sure to thoroughly seal them.
Satellite Dish Receiver
This can be a rather complex subject beyond the scope of this article. Suffice it to say there are several different types, ranging from simple manual crank-up dishes to full in-motion systems.

Contributor: WxToad, Buckeye707, Danny, Larry Wade

Revised: 7 Apr 12

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