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Tom Bray · 06-17-2008, 10:08 PM

Unfortunately my AS doesn't appear to have a spare tire under it.

What I have done so far, since I had everything removed from the insides, was to run 2 coax cables and a control cable next to the Blackwater tank in the back. Currently the coax and cables go into the rear locker by the bumper through individual water tight fittings. I am thinking about replacing the fittings with SO-239 barrel connectors and put covers over them when not in use. For the control cable I was thinking of using a trailer vehicle connector with a cover over it.

My reasoning for doing it this way is to keep the cables from lying in the bottom of the locker and sitting in water. That is where the cables are now and one of them already has water in it even though they were taped up.

Has anyone ever tried this? How fast did the connector die? I have plastic covers for the barrel connectors when they aren't in use.

I am still contemplating how to put the VHF/UHF antenna on the roof. One thought was to use the Fridge vent (someone on another thread came up with that). I think Comet makes one of those motorized mounts that will lower the antenna when it isn't in use. I am worried about the stress on the vent.

My other approach for the VHF antenna is to put it in place of where the TV antenna control came out. The old antenna is gone and there is a large sheet of aluminum covering the area.

Any suggestions?

Thanks

Tom Bray
WB8COX

olddog299 · 06-18-2008, 01:39 AM

Quote:

Originally Posted by Tom Bray

What I have done so far, since I had everything removed from the insides

How about setting up a couple of stainless steel mounting plates, while it's all open, tied to the roof "ribs"? NOW is the time to make sure your antenna mounts will be bullet proof in, oh, a hundred mile an hour wind, so you can do emergency services duty. The VHF shouldn't be too much of a problem and putting in strongbacks for anchoring points in case of putting a heavier beam or other antenna into play should be a cinch with everything open. Also a great time to install those pass-thru's and the like -- the Shack used to sell a nice Lexan pass-thru with replaceable caps which allowed one to do whatever you want while retaining the ability to have only temporary installations remain watertight between uses.

BTW, not currently a Ham, but am thinking about it.

Good luck!

B4WEDI · 06-18-2008, 04:51 AM

Jetstream dual bander 2M & 70CM

Works great and a clean install if I do say so myself !

I came in through the A/C trough which gave me clean open access to the inside

Tom Bray · 06-19-2008, 06:08 PM

I had the TV antenna removed when I had the dealer install a new air conditioner. It was in very rough shape anyway. They covered the holes with a large (12" square) piece of aluminum.

I have decided to put an NMO mount near the front vent and run the wires past the vent and into the front area. I am planning on using one of those 12" high 2m/440 antennas so the height doesn't get unreasonable.

I plan on leaving the fridge vent area clear for now in case I want to put a cell or internet antenna there.

That will give me 3 ham antenna possibilities which should be enough (I know it won't be but what can you do?).

Tom
WB8COX

DPeakMD · 06-19-2008, 07:53 PM

Good ideas abound!

The metal of the fridge vent is very flimsy. I'd stick with a small antenna as Tom mentioned. Mount it closer to an end which is supported.

The other option would be just flush mounting an NMO-style antenna near the middle of the trailer. It's easier to get access underneath on the inside in that location. Then you can use the length of the center strip as a cable tray if needed.

B4WEDI, I really like the idea of putting it on the crank-up TV antenna! That's a good one!

olddog299 · 06-19-2008, 07:57 PM

Nice job - having that overhang on the shroud of your A/C must have been a help. It does look very clean.

Tom Bray · 06-19-2008, 10:06 PM

Well I shot a 3/4" hole in about the same spot that the old TV antenna control went up through the roof. Mounted a reasonably decent NMO (I think it was Antennex) antenna mount. The trick with the installation is to get the mount to line up in the hole so that everything tightens down correctly and doesn't spin.

The ring that holds the mount in place has a rubber grommet along its lower edge so it makes a pretty good seal. The antenna had an O ring that provided another seal.

I have a short, maybe 18" long antenna that I had on one of the other cars that I installed and that worked out pretty good.

I already had the roof vents removed for servicing so I removed a few rivets from the ceiling area and was able to get it down far enough so there was room to fish the coax through to the control panel area. There are slots in the ribs on the port side of the ceiling channel that allow RG8X to go through nicely all the way up to the front. I used an unbent coat hanger to fish the wires through the holes and insulation.

I also had the windows and the lower panels removed in front (due to looking for water problems) and I had enough rivets removed so I could get at the AM/FM radio antenna (I am about to replace that too). So I was able to fish the cable from the ceiling area down to the floor without too much trouble.

I wiggled the antenna and it doesn't appear to have enough mass or length to vibrate the roof much at all, it is surprisingly solid considering how flimsy the roof area is. I don't think I would want to put a really big antenna on it though.

Be very careful with the roof. I pretty much stayed on the ladder. I also used the nifty pad that a mechanic friend gave me that is really for lying on or sitting on. It is about 1" thick and made of fairly solid rubber, sort of like one of those garden knee pads but larger. I put that down on the roof so that when I put my hand out I didn't deform aluminum. It worked pretty well.

Tom
WB8COX

pixiehat · 01-15-2009, 10:40 AM

Those are great ideas for UHF/VhF which of course was the point of the thread i guess. To get a little off topic and, pretty late actually as this is an old thread, My AS has a hitch reciever on the back. I had a mount made that pokes up 4 or 6 feet depending on my mood to mount my new HI Q. Havent put any smoke to it yet as I'm still waiting for the weather to clear enough to run upstate to get my trailer. Will be exciting a Henry 3KD Classic with a TS2000. Got the trailer to serve as my ham shack. Secondary use will be travel. One must get ones priorities in proper order.

73
Lee
NI7I

Tom Bray · 01-16-2009, 01:17 PM

The HiQ should work pretty well. I have been drooling over them for quite some time now.

I did pick up a 6" diameter bug catcher at a swapfest earlier this year and now have a mount on the AS's rear bumper. The little testing I have done with it so far indicates that it blows the doors off of the Hamsticks that I have.

I still have a couple of months of work to do on my AS before it can go out again, plus I keep adding more stuff to do to it.

One feature I am also considering is to use a drain pipe in the front with one of the sewer covers on it and pass cables through it so I can have more antennas. To hold it in place I was thinking of using the top part of 3" drain valve (maybe I'll use the whole valve so I can close it off inside).

I picked up a fairly heavy duty 25' flag pole that I can hang a couple of VHF and UHF beans on.

Tom
WB8COX

ffwilliston · 01-16-2009, 02:11 PM

Greetings. . . I have a FT-8900 and external speaker mounted on a small shelf (white board avail at any lumber supply) with rubber feet. In order to meet my wife's "no holes drilled" policy, I use an external antenna that is situated on a mag mount that goes on my tow vehicle (Nissan Armada). Using a double female through a bulkhead connecter mounted in one of the battery boxes drain holes (on the front of the trailer), no drilling is required. I simply screw on the (four band) antenna's coax connecter to and place it (mag mount) on the Armada. The other end of the through-bulkhead is connected to a short patch coax that connected to the rig. Since the DC supply for the trailer is mounted under the couch, I run the coax cable parallet to the suppy connection that supplies the 12 volts. Both cables tuck away under the couch when not in use and the rig itself hides in the over-couch cabinet. I have gotten very good signal reports, including activity on the 10 meter FM calling channel, with this setup. Since the tow vehicle is almost always parked immediately in front of the trailer, I alway have it available and it is easier to get to than the top of the trailer. Photos available on request. Good luck. Fred, AF4MB

w5wi · 01-16-2009, 03:52 PM

All good ideas!

On my vintage airstreams they both have a radio antenna coming out the street side. It would be easy to replace that antenna with an old 102 inch CB whip cut to 10 meters. That with a good tuner would allow access to most HF bands.

cheers,

dale

mistermike · 12-08-2009, 03:08 AM

I am thinking for HF that an OUTBACKER mounted on a 6' piece of mast with a quick disconnect attached to the 'A' frame would probably be the best way to go.

73,

MisterMike,
W1RC

sailors · 12-08-2009, 09:18 AM

Hi,
I have a sidewinder mounted the jack post on the front of our 2006 20ft Safari. Havent run cables inside yet, usually set up outside on a table. I get a lot of company when operating. 2M i keep in the truck. Good luck. Mike N6ERU

Ag&Au · 12-08-2009, 09:40 AM

Quote:

Originally Posted by mike dean

Hi,
I have a sidewinder mounted the jack post on the front of our 2006 20ft Safari. Havent run cables inside yet, usually set up outside on a table. I get a lot of company when operating. 2M i keep in the truck. Good luck. Mike N6ERU

I have not decided what to do about an HF antenna. I am concerned about the large aluminum object being close to a high Q mobile antenna.
Is this the type of sidewinder antenna you are talking about?
Snyder Antenna Systems | an extensive history of finding answers to tough RFID problems!
If so I would like to find more info on it.
I have one of these and am considering using it near the trailer.
http://transworldantennas.com/
However the instructions say to keep it 50 feet away from large metal objects. I am pretty sure that includes an Airstream.

Thanks,
Ken W7TS

mistermike · 12-09-2009, 03:56 AM

Quote:

Originally Posted by w7ts

I have not decided what to do about an HF antenna. I am concerned about the large aluminum object being close to a high Q mobile antenna. ......

However the instructions say to keep it 50 feet away from large metal objects. I am pretty sure that includes an Airstream.

What? I would think that you would WANT a "large metal object" such as a trailer and tow vehicle UNDER the loading coil to act as a ground plane. Otherwise much of your presious RF is wasted.

Of course you need to get the loading coil high enough so it clears the top if the trailer; otherwise it won't be anywhere near as effective. The problem with using a "Bugcatcher" type center-mounted coil vertical is that you have to be able to conveniently reach the coil to change the taps as you change bands. I use a fold-over mount that makes this chore much easier but I still need to stop and physically get out of the vehicle which sometimes is not very convenient or safe. Still, this arrangement is preferable to using a tuner which is much more convenient. However, when you use a matching network there are going to be losses.

Finally you would probably want to use a capacity hat of some kind to maximize your mobile antenna's effectivness and increased bandwidth, especially on 80/75 and 40 meters.

My good friend Neil K6SMF drives a mini-van all over the country going to hamfests and flea markets. He has an Outbacker smack in the middle of the roof on a mag mount. He works all kinds of DX on 17 and 20 meters.

Never forget that HALF of the antenna system is the part you don't see - your ground. This is the secret that goes back to the very eariest days of radio.

I apologize for any non-amateurs for this semi-technical discourse.

73,

Ag&Au · 12-09-2009, 09:18 AM

Hi Mike,
Most of what you said I agree with, but it does not pertain to what I was talking about. I am not going to attempt to find a way to mount a HF antenna on roof of an airstream trailer. That is the only way you are going to get the trailer shell to act as a ground plane. It is not the loading coil that has to be above the trailer, it is the base of the antenna. Unless you have modeled it, there is no telling what the pattern of your antenna looks like,but I would guess it is pretty strange.
The antenna I have does not benefit at all from a ground plane. It is a half wave, center fed, and capacitively loaded dipole. Did you look at the link in my post? I have had experience with HI-Q antennas in proximity to other metal objects. They don't work well in any sense of the word.
If you want to continue this discussion, please PM me and I will send you my email address.
Regards,
Ken

airedale · 12-09-2009, 09:41 AM

YAY! I love ham talk!

W8JUZ

SailAS · 12-09-2009, 10:12 AM

If you've been a Ham long enough you may remember an HF Mobile
Antenna made by Webster (long since OOB) known as a "Band Spanner". It's basically a center loaded whip with a rather long center coil fed with a copper sprial tape from the bottom. The antenna is less than 1 1/2" in diameter, a good radiator (easy to match) but is pretty heavy. Does not work well on the bumper at speed w/o a good HD Spring mount.

I have intentions of putting mine on the AS for HF and than doing what B4WEI did for 2m (that is a slick install!!!). I have the same issue discussed earlier (how to get it above the Coach).

Has anybody seen a "Fold-over" mounted on the AS bumper or A-Frame?

SailAS
WA5IDX

aircooled4 · 12-09-2009, 11:14 AM

Ive given some thought to using the existing TV antenna for 2m/440...This spring Ill be redoing the AM/FM antenna. Would like make that spot available for something ham related...

Mikethefixit · 12-09-2009, 11:43 AM

I have a bracket mounted on the side of my tower with a HF Mobile antenna with a quick release and break over for easy changing of the coils that I use for vertical operations here are home. I have not tried this as of yet but I am considering modifying that mount to work on the AS.