antennas?

forgot to ask, for mounting the XM box... what would be neat would be something like the vibration mounts for an ignition box... but in a sticky back flavor. Does anyone make anything like that? I know there are sticky back standoffs for PC boards and I think they'd ALMOST work but I think I would prefer something with a little vibration isolation and a real threaded stud, not a plastic clip.

nate

Yes. XM will sell you one for permanent install that works nicely.

Yes. At 27 MHz, the wavelength is about 35 feet long... so even a quarter-wave antenna is pretty big. There is no substitute, sorry to say. Pretty much all of the antennas out there are less than a quarter wave and have a loading coil at the bottom to make the transmitter happy, but the coil really doesn't improve the effectiveness, it just makes the transmitter see a proper load.

There are some smaller antennas out there, but they are much less effective.

--scott

I just went to the hardwarestore.com store (Aubuchon) and got some super velcro and velcroed it to the ashtray (I smoke but never use them..). But then, with 3 different cars on the road at any time...

Interesting story. When I was back there in seminary school, there was a student who put forth the...er, I mean when I was going to my exclusive New England prep school, there was a guy there who played a mean guitar. He also played a mean banjo and fiddle. He was from eastern Mass but wound up living with his brother in Vermont for a while.

I got into a band with a guy and his wife, and we were talking about his annual summer party. He mentioned the guy's name...wait, how do you know HIM?!?!? The guy's brother and my friend's brother are brothers...you know what I mean. So, I went to school with him! No, I didn't see him at the party cause I was sick that year. Bummer!

My drummer friend looks at me and says... "Did you know his father invented Velcro?"

Sure didn't!

Yes, they will. My first XM was a Roadie, and that antenna was always a problem.Too many wires of all types. When we bought a new car a couple of years ago, we got XM added to our car system and the antenna is a little nub of a thing mounted in the space under the backlight (rear window). Most wouldnt even notice it.

I am buying a new car within the next week or so, and would also like to have CB capability (if anyone out there still uses it), but the large antenna is a detractor.

The CB channels are still used by truckers, and they're still very useful on long drives to get traffic information from folks coming in the other direction. If anything, they are more useful than they were back in the days when everyone and his brother were yammering on the bands. Don't expect much in the way of conversation, though.

You can get a magnet-mount antenna that you can remove when you aren't using it, and just put it up for long drives when you need it.

--scott

Any particular model that you would recommend?

I'm thinking of trying to work a setup that would be easily moveable from car to car, although I don't know how well it would work. I understand that the radio chassis likes to be well grounded, would grounding to a lighter plug be sufficient, or would I need an aux. ground as well?

nate

If you just want to listen the antenna can be quite small. To transmit the antenna must impedence-match the transmitter. A quarter wave antenna is an easy way to do this, but it is possible to shorten it with a technique called base-loading, which uses a coil at the base, and the antenna will be shorter. However, the larger the coil and the smaller the radiating element, the less efficient the antenna is, so you would not have as strong a signal with antennas which are too small.

I've had very good luck with the K-40 brand antennas. I have a K-30 model that works very well and sounds just like what you are looking for. You can check it out here. Click on the link to read the review also.

If that doesn't work try this.http://tinyurl.com/d2ptv7>> I'm thinking oftrying to work a setup that would be easily moveable fromcar to car, although Idon't know how well it would work. I understand thatthe radio chassis likes tobe well grounded, would grounding to a lighter plugbe sufficient, or would Ineed an aux. ground as well? The lighter plug should work just fine. I run myradio that way and withthe above antenna it works great.>> nate>> --> replace"roosters" with "cox" to reply.>

I have a 140 mile commute.

After years of trying, I am currently running a Cobra 29LTD with a Wilson antenna.

Don't scrimp on the antenna. A shitty radio will work great with a good antenna

thanks for the recommend. Are all Wilson antennas decent, or are there ones to avoid? A web search kind of indicates that they are good, but there's a lot of fluff out there. Was thinking of just getting one of the lower-priced magnet mount antennas as this will be occasional use, and also likely receive-only barring emergencies.

Is a SWR meter really required, or is it just a "nice touch?"

nate

Wilson is TOTL, a "fire stick" is good too, longer is better. As mentioned in this thread a 10 meter signal is almost 40 feet in length. A four foot stick is necessary to "get out". If you are primarily just going to DX, a cheap Uniden and magnet mount will do.

An SWR meter is a great help in tuning a good radio. You may not really need it if you just listen.

My addy is good and I have a spare rat-shack SWR meter I'll mail ya if you go large.

Al

heh, well guess what, I have a cheap Uniden, and really inexpensive too :)

so I shouldn't even consider a 3' antenna?

I really appreciate the offer, but a quick google shows that there are some available for $20ish... unless you are invoking the magic words :)

(my friends know what they are... "you see this part for a 50 year old car/obscure tool/whatever? I don't need it, and it wouldn't bring any money at a swap meet... I'm going to THROW IT IN THE TRASH UNLESS YOU WANT IT." This causes an uncontrollable reflex action that makes "upstairs at my garage" look like Fred Sanford's yard...)

I guess the reason I brought it up was that I'd seen dire warnings on a web search about how a way-off SWR would let all the smoke out... but yes, unless I'm convoying with some other guys with CBs, I probably would never transmit... unless I'm REAL bored. :)

Truth is, I'll probably never use the thing, except on road trips. My thought process behind getting it, other than the fact that the opportunity was there to get it for almost nothing, was that my employer takes a dim view of radar detectors (as in, if they find one in your car, they take the car away) so if I ever want to take a road trip in the company car I wouldn't be able to use my V1, so I thought that maybe listening in on CB might provide a somewhat-acceptable substitute... Granted, I've done plenty of long drives without any electronic countermeasures whatsoever, but you can never be too safe.

nate

Perhaps your employer needs to be introduced to the studies produced by the insurance industry that all showed that people using radar detectors were safer drivers. Those studies led to the SAS/SWS radar detector construction / ambulance / emergency warning systems.

I could try, but I don't think I'm particularly high up on that food chain. I think that there are some people who listen to me when I have product suggestions, but fleet policy... not so much.

I think if I *did* have influence, I'd try to get myself a Jetta TDI before I'd try to fight radar detector policy :)

nate

Studies have found that people who don't speed in the company car don't get speeding tickets in the company car. I know it's a crazy idea but.....

Steve B.

My wife has a K30 magmount in her car (and sometimes on it, on long drives) and it seems an okay performer.

At the truck stops I often see these little things that have a post about a foot and a half long, and then an insulator, and a driven element about two feet long... they use the bottom part as a centerpoise in theory... but actually they don't work worth a damn. Avoid them like the plague. They seem aimed at people who want a temporary antenna for occasional drives but they don't work well for that either.

With these things, tuning doesn't actually change the antenna resonance, it just changes the load the transmitter sees. Since the antenna is way shorter than optimal, there's a loading coil that makes the transmitter see a proper load. Adjusting the loading really just makes the transmitter happier and reduces the loss through the feedline... but your feedline is only a couple feet long anyway. So if the transmitter is happy and doesn't go into protection, you're doing as well as you are going to do under the circumstances anyway. Don't worry.

--scott