Jeff, thanks for your reply.

The XM/Onstar antenna is just above the top edge of the rear windshield on the Malibu. You said that the AURA had that antenna "near the windshield" (would that be the front or rear one)?

You drilled a hole about 8" from the rear window edge, did you notice any 'braces' or other reinforcing pieces near the location that you selected? Were there any cables for the broadcast (or XM/Onstar) radio or other equipment near to that location?

You said that your radio was mounted in the trunk. Did you run your power wires all the way to the battery (as K0BG has stressed as 'best practice' on his website)? If so, could you provide a brief description of where you located those wires, and most importantly how you got the wires from the cab to the engine compartment in the AURA? Is there a convenient grommet in the firewall that can be used, etc.?

Thanks,
Dave N4DBC

Clint, I've already got an Austin 500C (2m/70cm) antenna (about 18" high, metal <not the flexible model>), and a NMO mount/cable. I'm just looking for some details on mounting on the Malibu roof. I'd much prefer to mount it there, but with all the bracing, side-air bags, accessories that could be affected by dropping the liner, I'd really like to hear from someone who's already done a roof-mount on this model car.


Alan, I am considering using a hood seam mount if I don't find someone who's familiar with the new style Malibu (for mounting antenna on roof). I have browsed some 'hood-seam' mounts, which may work on the Malibu, but the seam clearances are pretty tight (even considering it is a GM...ha). Thanks for the suggestion.

You're right about the trunk opening, it may even be a little more than 90 degrees, which means even the small antenna would hit the rear glass (hard if you're not paying attention...like my wife......uh, did I say that out loud?)

73, Dave N4DBC

Antenna mount information for 2009 Chevy Malibu

I posted the following questions in the "Elmers" section of eHam a couple of months ago, and didn't get much of a response. I noticed that the quantity & quality of responses to similar questions is much better in the "MobileHam" forum, so I'll try it here. K0BG has good information, but not specifically for my vehicle.
   
I was hoping that someone has more specific information for a 2009 Chevy Malibu (new style Malibu).

I've read that you can take the dome light off of some vehicles, and get enough access to make the hole for an NMO mount, without having to remove the whole roof liner (or a big part of it). Has anyone done this (specifically) on a 2008-2010 Chevy Malibu? (new style Malibu)?

Do you recommend routing the coax to the left or right, front or middle (or even rear or c) pillars? There are 'tweeters' for the stereo in the front pillars, and seat-belts (and who knows what else/airbags?) in the side pillars. I know that the xm radio/onstar and broadcast radio antennas are near the rear of the vehicle. Do you know how those cables run (under the roof liner, rear pillars, etc.)?

If you had to remove the liner (whole or half) to do the job, are there any 'pitfalls' that I should look out for that are specific to this vehicle?

I'm not so much afraid of drilling the hole in the car, as long as I know that I'm not drilling into anything that's important, like roof braces, and that I can get the coax routed without too many headaches.

I thought about putting the antenna on the trunk, but it opens so far that the antenna will strike the rear glass. Besides, the roof is preferred if not too much trouble.

Thanks for any assistance!
73,
Dave N4DBC

<Quote>from N6AJR: "go to the junk yard and buy a matching lid from a werck that matches the color of your car. drill this one any way you choose, and when selling the car later reinstall the original lid." - </Quote>

Nice advice, about an "original lid" and such. Thanks

I know that there are plenty of topics on eham.net talking about NMO mounts for antennas on vehicles.

I've read a few of them, but was hoping that someone has more specific information for 2009 Chevy Malibu.

Some folks say that you can take the dome light off of some vehicles, and get enough access to make the hole for an NMO mount, without having to remove the whole roof liner (or a big part of it).

Has anyone done this (specifically) on a 2008-2010 Chevy Malibu? (new style Malibu)

Is the dome light difficult to move/remove if I want to try drilling that way?

In any case, should the mount go in front of or behind the dome light? Do you recommend routing the coax to the left or right, front or middle (or even rear) pillar?

There are 'tweeters' for the stereo in the front pillars, and seat-belts (and who knows what else) in the side pillars. I know that the xm radio/onstar and broadcast radio antennas are near the rear of the vehicle. Do you know how those cables run (under the roof liner, rear pillars, etc.)?

If you had to remove the liner (whole or half) to do the job, are there any 'pitfalls' that I should look out for that are specific to this vehicle?

I'm not so much afraid of drilling the hole in the car, as long as I know that I'm not drilling into anything that's important, and that I can get the coax routed without too many headaches.

If removing the liner is too much trouble, or if it is a 'pain' to get the coax through and out out of the liner, pillars, etc., then I'll just put the antenna on the trunk (it's not much lower than the roof on this car anyway). However, you know that 'real hams' want their antennas as high as possible, so the roof is preferred if not too much trouble.

Thanks for any assistance!
73,
Dave N4DBC

FROM: KC8HXO on June 18, 2008
http://tentecwiki.org/doku.php?id=crackedknob

This fix works well.

73-
Greg, KC8HXO
---
Greg,

That is an excellent idea! Thank you for sharing it with everyone (especially me). I Googled for something like this webpage, but obviously didn't use the correct 'keywords'.

I superglued the old knob back together for a temporary fix. I'll definitely do the "JB Weld Mod" on the replacement.

73,
Dave N4DBC

I received this message from Paul WD4EBR at Ten Tec:

"Dear Dave:
 
Yes, we have a different knob that is reinforced, $3.00 each plus $3.00 shipping and handling.
 
73,
Paul R. Clinton
WD4EBR
Service Manager"
---
I'll order a couple to see if they are better than the original knobs.

I'm still interested to hear from anyone who knows of a source of replacement knobs with brass inserts. I know that the antenna switch shaft has certain measurements that you'd have to match. I'll have to try and find my calipers or something small to take measurements, and hope that there are common size knobs that would fit.
---
W5GA on June 17, 2008     
"I got a new knob from TT, and no brass insert. They last just fine as long as you don't strong arm the set screw...that's what breaks them."

I'll keep that in mind. The way that the knob cracked makes me think that the set screw was overtightened. Maybe the previous owner had to take the knobs off in order to 'restring' the inductor indicator pulley or something.

73,
Dave N4DBC

WB0MCO - "I had the same problem the knobs are junk! No amount of Lub as suggested could fix the problem. I replaced the knobs with new ones that had brass inserts, the way "real" knobs are made,that way when you tighten
the set screw the knob would't crack."
---
Thanks for the comment. Did you buy new knobs, and if so from where?

I looked through the "junk pile", but none of the knobs that I tried would fit.

If anyone knows a source(s), other than hamfests, of suitable knobs (that sounds funny huh), then please let me know.

73,
Dave N4DBC

I purchased a used Ten Tec 238 tuner, and the antenna switch knob is cracked, making it unusable.

The construction of the knob is not very good in my opinion, as there is nothing but plastic and a set screw.

Not that the switch requires "lots of force" to turn, but I would have expected some sort of metal reinforcement in the knob, but there is none.

I've written to Paul Clinton at Ten Tec about a replacement, but if they have not changed the design, then I'd rather go to an aftermarket source.

If anyone has already gone through replacing the antenna (or the "bypass" knob, which appears to be the same), then I'd like to hear from you.

If you got a replacement from Ten Tec, was the construction any better than the original? If not, is there a simple modification that will help the knob last longer?

If you didn't get a replacement from Ten Tec, could you make some suggestions so that I don't have to 'guess' where to go and what to order?

Thanks in advance!
73,
Dave N4DBC

It's just not right, all of these liberals running ads on eHam!

|

Just kidding! If google is helping to pay the bills, and they get an ad space, then I guess it's ok. BUT I'M NOT KIDDING ABOUT BOTH OF THE CANDIDATES BEING LIBERALS! Ha

If you don't want to see the ads, then download the Firefox browser and add-on extension AdBlock with AdBlock filterset.g updater. I would not have known about those ads except from the complaint by NI0C.

I know that we don't rate Internet browser software on eHam, but for me Firefox is 4 of 5 while Internet Exploder is 3 of 5.

73,
Dave N4DBC

Gray is a good hamfest. I've gone for the past two years.  

There are enough 'tailgaters' to make hunting for bargains interesting. Not too much junk (like 12 year old pc's, 15 year old Atari video games, etc.), and I hope that they keep it that way!

I went to a 'swapfest' in Winston-Salem, NC a few years ago, and it was a total waste of time. There may have been a few decent items right at opening time, but I came about two hours after opening and there was nothing but junk! So far, Gray easily beats Winston-Salem.

I saw some decent Ten-Tec, Icom, Kenwood, Yaesu, and other used equipment at Gray. Of course, you would have to be a good 'haggler' to get the prices to decent levels. But at least there was something to 'haggle' over.

Gray needs more dealer participation, but they have more than most of the small hamfests that I've been to in the last few years.

If you live within three or four hours of NASCAR's Bristol Motor Speedway, then you should consider attending the Gray hamfest next year.

73,
Dave N4DBC

I went to Gray again this past weekend.

It's not a Dayton, Shelby, or even a Charlotte.

It is a great little hamfest.

The sponsors have done a great job, and I hope that they continue to do so.

73,
Dave N4DBC

Yes, I said 3-legged.

I'm interested in trying a Y-doublet as described by L. B. Cebik, W4RNL. I know that won't give me any gain over a normal doublet, but you can somewhat control the direction of signals.
link - http://www.cebik.com/edz/wy.html

Perhaps there are some industrial engineers, manufacturers, etc. among the eHam community that might know of a suitable material to make a triangular (or round) spacer as described in the article.

To quote the master himself: "We can create a trio of pairs by using circular spacers of the type shown in the figure. For HF work, Plexiglas or polycarbonate spacers should be satisfactory. We can cut a hole in the center of each to reduce the weight. The holes can actually be slots if we add bridge wires to hold the spacers in place. In essence, we are adapting techniques normally used to create caged elements and applying them to the feedline. Such lines might permit the use of the antenna on all bands with a wide-range antenna tuner and will go a long distance in maintaining something close to the modeled ideal geometry we used in the test cases."

My question (or challenge) to anyone caring to participate is as follows:

Does anyone know of an economical (and easily attainable) source of materials that could be used for spacers?

Please keep in mind that a lot of folks don't have a lot of tools or experience that could be used to fabricate these spacers (especially me).

I looked for some material to use from McMaster/Carr, and it seems to me that it would take considerable time, tools, and expense to fabricate spacers from the prices and types of material that were available at their website. Maybe I was not looking at the site correctly, it is somewhat complicated due to the nature of their business.

I would like to find a source of suitably sized discs, triangles, etc. that are commonly used in some fabrication or industrial application that I'm not aware of. (but someone out there might know about)

If so, I would very much appreciate any suggestions.

Also, if someone knows of a pre-made or easily made switch that would allow switching between legs A - B - C of the Y-doublet (either at the rig or remotely), that would be great too. Please name sources (especially Internet based) for these parts too if you don't mind.

If I had the time, tools, & money then I'd just go for it from scratch. However, the reality is that if I can't find something that can be easily (& quickly) used for spacers, and still economical (read: cheap), and yet still light and tough enough for outdoor use, that this antenna project will probably be dropped for a simpler doublet/dipole or horizontal loop.

I know that this sounds like I'm trying to get out of all the work to make the antenna/feedline. I'll admit that if there was an antenna dealer who made a kit that I'd probably look at that first. However, I'm just trying to do as little as possible, without having to "reinvent the wheel" (or spacer) so to speak.

Any helpful advice, links, articles, sources, etc. will be appreciated.

73,
Dave N4DBC

Thanks for some good answers. They have given me some different things to consider.

73,
Dave - N4DBC

I've been considering buying a balanced tuner because I plan to primarily use a single balanced loop or doublet as a multi-band antenna at my QTH.

The tuners that I'm interested in are the MFJ-974HB or the Palstar BT1500A. I know that those tuners are "light years" apart in quality and design, and some people will want to comment on those differences alone, but please stick to the topic of whether using either of the balanced tuners with a balun on the output & feeding coax would be practical (to an ant. such as a trap vertical, etc.).

I can't see any reason why that wouldn't work, but I know that there are more "learned" folks here that could either verify or expound upon my question further.

Someone may have addressed this question before, and if so I apologize, but I could not find the answer on a quick search.

73,
Dave N4DBC