AI roof structure (need to put stuff up there)

[sheakev]

I want to add some things to the roof of my 2017 AI. The existing solar panel appears to be bolted or screwed in. The tops of the bolts or screws are covered with the grey calking which appears to be use whenever there is a penetration, e.g. A/C unit.

I want to add more solar panels and a couple of antennas, one small the other will be larger and only deployed when parked, both for ham radio. The larger one will have a plate which will need to be fastened to the roof.

So, I know the top layer is steel. But what is under it? Are there any drawings showing the layers/construction of the roof surface (outside) thru the ceiling (inside)?

If screws can be used any specs on the length or depth for such screws?

P.S. I have attached a picture of the large antenna mounted on an RV. I intend to mount mine on the roof not on the side as depicted there.
The other picture is the motorized mount and lift which would raise the antenna from a traveling horizontal position to a vertical position when the AI is parked. The picture of the pickup truck is for perspective of the size of the antenna.

[Lily&Me]

Your best source for that information may be Airstream, itself.


Maggie

[Protagonist]

For mounting that large antenna base for the fold-down antenna, your best bet is to mount it near the rear, folding forwards, or at the very front, folding backwards. Probably on the driver's side in either case. My preference would be to mount near the front so the antenna is more-or-less over the driver's door

Both locations offer an advantage— you can access the underside of the roof through a storage compartment. Remove the inner liner and any insulation to install the backer plate*, and through-bolt from the motorized antenna base to the backer plate. Once that's done, you can replace the insulation and inner liner in the storage compartment.

*You were planning to use a backer plate for rigidity and to distribute the load over the entire surface area of the base instead of concentrating the load on the roof at the bolts, weren't you?

[sheakev]

Originally Posted by Protagonist

For mounting that large antenna base for the fold-down antenna, your best bet is to mount it near the rear, folding forwards, or at the very front, folding backwards. Probably on the driver's side in either case. My preference would be to mount near the front so the antenna is more-or-less over the driver's door

Both locations offer an advantage— you can access the underside of the roof through a storage compartment. Remove the inner liner and any insulation to install the backer plate*, and through-bolt from the motorized antenna base to the backer plate. Once that's done, you can replace the insulation and inner liner in the storage compartment.

*You were planning to use a backer plate for rigidity and to distribute the load over the entire surface area of the base instead of concentrating the load on the roof at the bolts, weren't you?

I would likely mount it forward, on the driver side. Assuming that the roof layers are just steel, insulation, and liner I agree a backer plate would be essential. Alternatively, I could use a bull bar to mount it but really prefer to have it inconspicuously mounted/ stored on the roof.

Still wondering how the one solar panel was attached, bolts or metal screws?

[Protagonist]

Originally Posted by sheakev

Still wondering how the one solar panel was attached, bolts or metal screws?

Possibly neither. Could be 3M VHB tape.

[Lotus54]

Another consideration is the amount of RF energy you get. Having it on the roof, especially back from the windscreen a little blocks most of it getting to you (plus generally a null under the antenna anyway).
I installed many, many VHF public safety radios, 50 or 100 watts.
The general rule we used was 6feet away from you- when in radiation ‘zone’.
(If at all possible).

Of course all depends on how much you use it, but HAM guys tend to use it a lot is seems and I know I don’t particularly like any excess exposure. I did do some testing with the testers, and roof mounted on a metal roof wouldn’t even budge the gauge when xmitting

Probably all stuff you have thought about or know about.

Mark

[InterBlog]

I'm liking this thread. Question: would it be possible to replace that attached, articulating style of antenna shown in your example photo with a telescoping model of some sort? Which is maybe installed on a lower-down bracket from which it can be extended?

Those of us who are trying to maximize the use of a "shark fin" style directional cellular antenna face a similar need for height above the roof line. I hadn't found any roof-mounted hinged antennas that I felt confident in installing, with or without backer, mostly because of the anticipated roof stresses especially in a sudden wind and the potential for any malfunction of the contraption to shatter our solar panels (one fall could be catastrophic across multiple systems). But neither had I completed my research. I got diverted into the potential for a telescoping antenna mast instead, perhaps one that could extend upward from either the ground, and/or from our custom hitch carrier, for which a very strong welded receiver could be fabricated that would be much safer than anything attached to the thin sheet metal of the van body. But I had not completed that research either.

I understand the urge to be inconspicuous. In my case, I was planning on dismounting the telescoping antenna and, depending on its folded size, either store it inside the van or lash it to the roof rack when not deployed. Either way, it would not be noticeable.

[FlyFishinRVr]

Originally Posted by sheakev

Still wondering how the one solar panel was attached, bolts or metal screws?

Metal screws covered with Dicor self-leveling sealant.

FWIW, if I were to add more solar panels, I'd use a combo of VHB and Dicor. The VHB would be used at the corners and mid-point where the grommets for the screws are, then I'd screw through the VHB into the roof, then cover the screw w/ Dicor. Can't imagine it would ever leak or come loose....

[sheakev]

Originally Posted by Lotus54

Another consideration is the amount of RF energy you get. Having it on the roof, especially back from the windscreen a little blocks most of it getting to you (plus generally a null under the antenna anyway).
I installed many, many VHF public safety radios, 50 or 100 watts.
The general rule we used was 6feet away from you- when in radiation ‘zone’.
(If at all possible).

Of course all depends on how much you use it, but HAM guys tend to use it a lot is seems and I know I don’t particularly like any excess exposure. I did do some testing with the testers, and roof mounted on a metal roof wouldn’t even budge the gauge when xmitting

Probably all stuff you have thought about or know about.

Mark

From the Sprinter manual:
Short wave < 50 MHz : 100W
2 m band : 50W
70 cm band : 35W

Just picked up an Icom IC-7100 transceiver which has maximum power of HF of 100 watts. And like you said with that big metal roof there will be a big margin of safety both for us and anyone nearby (per FCC regs).

[sheakev]

Originally Posted by InterBlog

I'm liking this thread. Question: would it be possible to replace that attached, articulating style of antenna shown in your example photo with a telescoping model of some sort? Which is maybe installed on a lower-down bracket from which it can be extended?

I understand the urge to be inconspicuous. In my case, I was planning on dismounting the telescoping antenna and, depending on its folded size, either store it inside the van or lash it to the roof rack when not deployed. Either way, it would not be noticeable.

The antenna I am getting has all its electronics in the bottom section. To that there is then a spring and finally a 60" whip. There are HF(shortwave) antennas which do telescope but I wanted to go with this one which is a military model ( rugged and hi quality components) rather than a commercial or amateur radio model. The antenna itself only weighs 11lbs, I suspect the mounting bracket and motor weighs more.

[InterBlog]

OP, you posted a pic... could you also provide sourcing information? Brand, vendor, etc. You said it was "military" grade.

It sounds like you might need a specific config for your intended use, but I'm wondering if your supplier sells other types as well. I ran into a brick wall on my initial searches for a telescoping mast because I cannot judge the quality of that kind of device over the internet. I need to get a "feel" for it and how I might mount it to our Interstate. So I either do an expensive and time-consuming trial-and-error run, or I somehow get referred to the best vendor from the outset and maybe skip much of the search.

Another reason why I was interested in a telescoping model - I already own one of the suction cup devices designed to mount an antenna temporarily on the side of a vehicle. That suction cup is a really good quality device (it was professionally recommended). So I thought if I had a telescoping model mounted off the hitch carrier, I might be able to use the existing suction cup to fashion a two-point attachment system, which would be more stable and secure (potentially) than a one-point anchor.

[Protagonist]

Originally Posted by InterBlog

Another reason why I was interested in a telescoping model - I already own one of the suction cup devices designed to mount an antenna temporarily on the side of a vehicle. That suction cup is a really good quality device (it was professionally recommended).

Folding and telescoping radio masts are a big thing in the boating community, where the need to lower antennas before passing under a low bridge is a perennial problem.

You might want to expand your search to boating supply houses like Defender Marine or West Marine for the type of antenna and mount that will work best for your application.

[sheakev]

Originally Posted by InterBlog

OP, you posted a pic... could you also provide sourcing information? Brand, vendor, etc. You said it was "military" grade.

The antenna was made by Stealth Telecom out of the UAE. My model is the 9300. There was a model made for amateur radio but it was a limited run and there are no plans for that model to be brought back. There is a NVIS antenna, model 9400 which is quite interesting but retails for over 10k although I was offered a demo for $8k, I passed on it.

The 9300 was favored by UN peacekeepers, it relies on HF communication (1.6 -30 MHz). There is someone on eBay offering the commercial version(9610) but I got a slightly better price by dealing with the manufacturer. and the 9300 has better components.

Is this overkill? Absolutely! But for me it was the ultimate in a vertical HF antenna, it is more than antenna, it has an automatic antenna tuner (matching network) built into the antenna itself. Can more simple cost effective solution, of course. Protagonist idea of checking in the marine world is a good suggestion.

Attached is a picture of the vertical antenna on a van and another picture of the NVIS (looks like a luggage rack). BTW, the antenna radiator portion (upside down U ) can be raised or lowered remotely and I am told that it is designed to have solar panels sit inside it so you don't loose roof space).

73, N9JKP

[rmkrum]

Neat stuff!

[InterBlog]

Thanks for the detail. The general subject of any kind of antennae on a Class B is very rare, and of course on the cell side, the technology is still evolving rapidly, so it's hard to know where the investment should be placed. If we are talking about a four-figure cost above and beyond normal supplemental receiver and boosting technology, my tendency might be to cross my fingers and hope that Kymeta gets its wider act together sooner than later (but I'm not holding my breath).

Even Technomadia, the undisputed mobile connectivity leaders, talk very little about this topic in either their subscriber or non-subscriber content spaces. They can recommend what equipment to mount ON a mast for a given scenario, but have less to say about how to choose the physical extension device (mast, pole, whatever) itself beyond the typical market offerings that generally include integrated antennae. But especially for long-range cellular connectivity using directional equipment, size matters. Height can make or break the result.

I'm curious about what kind of radio activity you engage in while on the road. The nearest neighbor to our Canada property is a radio operator, in part because it's an off-grid location with no cell service, so his radio is his only means of communicating with any part of the outside world. But I think he mostly uses it as a time-waster, messing around and chatting with random people here or there. The way he describes it, it sounds like a hobby with declining numbers, as people turn to other high-tech amusements.

[sheakev]

Originally Posted by InterBlog

Thanks for the detail. The general subject of any kind of antennae on a Class B is very rare, ...

I'm curious about what kind of radio activity you engage in while on the road.

The answer is none. If I am driving I don't even like to take a cell call using a bluetooth setup, but will if I am in familair open road way with no traffic. As to the amateur radio, I would only do that when parked. For HF (1.8MHz to 30 MHz) I would have to raise the antenna. If I had mounted it on the front (likely on a bull bar) then I could operate it whilst driving but with a roof mount that would not be possible.

Yes, amateur radio is fading (but so are all of us ) but it something that I have fun with and being to operate it from remote locations will be a joy in my AI.

[InterBlog]

Perhaps I should have said “while traveling”. “On the road” to me means the entire process. I was on the road for almost a continuous month earlier this year, but I probably only spent 100 hours of that driving.

I’ve watched my Canadian neighbor fiddle-farting around with his radio, saying “hi” to people. I’m wondering what else is achievable in that space. Are there chat room-like functions? Independent news sources? Special interest pursuits? Geographic connections? I’m not sure what kind of content is exchanged in that medium at this time, given the enormous growth of other options (internet-based).

[sheakev]

Originally Posted by InterBlog

I’ve watched my Canadian neighbor fiddle-farting around with his radio, saying “hi” to people. I’m wondering what else is achievable in that space. Are there chat room-like functions? Independent news sources? Special interest pursuits? Geographic connections? I’m not sure what kind of content is exchanged in that medium at this time, given the enormous growth of other options (internet-based).

If what you saw from your Candian neighbor was "fiddle-farting around with his radio" then ham radio is not for you. You will be much happier with the internet. There is a large technical aspect of ham radio which I enjoy. It goes well beyond the exchange of infomation using that medium. Whilst there are many of the elements of communication you reference, it can be challenging (a large part of the fun for me) to access them.

Everyday access to the interent becomes easier and more broadly available. If you find yoursel in a truly remote off the grid places there are some satellite phones that will give you that access and will be less than the cost and learning curve of ham radio. Thankfully, the days of a copper pair of wires to 300 baud accoustic coupler are long gone.

[Boxster1971]

Since we are discussing Ham Radio... did anyone see the recent episode of NCIS where Ham Radio played a major role in the story?

[sheakev]

I did and my wife has been calling me Rick O'Shea ever since.