I've considered swapping out the RC-style antenna for a stub, but I live and work in an area that has a lot of fringe signals. Since the RC antenna is tuned to the FM broadcast band, and reception is generally marginal/spotty already, I'm assuming that I'd run out of string with the stubs that seem to have lengths determined purely by aesthetics. The iPod is the main entertainment provider but sometimes you need to go live.

Now if someone would design and manufacture a stubby antenna with a loading coil to make it a 1/4-wave equivalent, we'd be good to go. Has anyone seen such an antenna?

I have the gear to test the resonance of FM broadcast-band (and other) antennae but where to start?

 

I have a 4" helix stubby, I think there is a little loss of reception. I use mostly sirius though now.

 

I bought a 3" stubby, and I havent lost any signal strenth at all.

 

Halifax,

Given how many FM and AM stations there are in your area, go with whatever size antenna you want. You could tune out the reactance with a loading coil, but in the North East your main problem is going to be line of sight, i.e. is broadcasting antenna behind a mountain.

 

personally, I thought the car looked better without the large antenna you get from the factory, so I plucked it

Looks much more sporty, to me.

I was considering having a fin, similar to the ones on the bmw's fabricated to fit my mini i know someone who could do it.

 

4in. Alta actually better than my stock was, but Im in Germany if this matters?

 

With my car sitting in my driveway and the radio tuned to an FM classical music station with marginal reception, I did some tests to see how reception was affected. Then tried a stronger station.

First with factory antenna, next with no antenna, third with the Craven Speed Stubby (not the half-size super stubby).

Conclusion: I could tell any difference between any of the options. I couldn't hear any difference between factory whip and no antenna at all.

I suspect there are situations where the factory antenna would pull in something that smaller antennas don't, but I could make it happen.

 

I put on an S2000 antenna and the reception sux. Looks much better than the long stock antenna though.

 

Any stub antenna will give worse FM reception than stock, because there are specific antenna lengths that resonate with specific frequency bands. The appropriate lengths are based on doubling or halving the wavelength at the center of the FM band (100MHz), or roughly three meters. An antenna half as long will capture less than half the signal strength of a longer one. Cut it down to 1/4 wave and lose more than 3/4 of the signal strength vs a full-wave antenna. The MINI stock antenna is an eighth-wave antenna - about as short as is useful.

You may not find the effects of a stubby noticeable, particularly in an urban environment where signals are strong, as FM is pretty tolerant of low signal strength, and the effect of moderate signal loss is the mostly missing high and low frequencies, neither of which you are going to hear much of in a MINI.

You can easily test whether a stub antenna will work for you by using the seek feature of your MINI radio, and counting the number of stations it finds when using the stock antenna vs. with a stub.

To do this without buying one, cut a piece of wire as long as the stub antenna you are considering, unscrew the stock antenna, and stick the wire in the hole.

Bottom line is that even if someone says "it doesn't matter," you will lose reception and fidelity with a stub antenna. Whether that matters to You is mostly a factor of where you live relative to the stations you listen to. I took my stubby off and now use the stock antenna again, as I live in a rural area - reception on the stations that matter to me was much worse with the stubby.

I recommend "The ARRL Antenna Book" as a source for anyone who wants to understand this in depth.

 

FM stereo is actually two signals, the station transmits a Left plus Right and at a lower power Left minus Right. This allows really old radios to detect Left plus Right which is Mono. The TV broadcast system that is going to be phased out does the same thing, the black and white signal and separately the chromiance information. As you put on smaller antenna, they lose gain and then you recieve only mono. Essentially FM reception is Stereo, Mono, or the station can't be detected. For AM as antenna gets shorter the volume would decrease, but since AM is around 1MHz and has a wavelength of 100 meters the difference in gain between the antennae under discussion wouldn't be noticeable. In the old days when car antennas were made of telescoping metal tubing, kids would break them off to play with. I've had good luck sticking coat hangers in the hole, and I even used a potato once.

 

I understand all the tech reasons why a longer antenna should receive better than a stubby, but reality seems to be different.
I tried the same tests as Robin did with the same results. My stubby was an Alta and at least on FM, I saw no difference with the stock, stubby or no antenna.

 

I have the one form OUTMOTORING, great reception

 

Robin and other respondents,
Thanks for the test and analyses. Always enlightening, and this one especially since I'm a longtime ham radio op. I'm going to pick up a stubby from OutMotoring and just keep the factory antenna in the boot for use when I might need it. I do live and motor in a fringe area, so...
Thanks again!

 

so essentially there are *5* places to get these:

outmotoring (~ $26)
craven speed (~$20)
alta (~ $30)
namotorsports.net (~$30) <-Perrin 2" an 4" stubby
way motorworks (~$20)

Am I missing any?

 

I have the Craven stubby (I don't know which version - I think it's about four inches long), and there are a LOT of stations that the factory antenna will pick up that the Craven won't. I've found this to be true in the Norfolk, Virginia area as well as around Monterey, California.

I wasn't too bothered by the aesthetics of the factory antenna, so I ended up putting it back on.

 

Hi Scott,
OK, that's good to know. Living in the fringe areas of a lot of stations, I imagine that if I swap to a stubby, I'll be running out of string too often.

Palo Uber makes a few different designs - including copper-core types - but I don't think that any stand out as signal magnets.

So the take-home conclusion seems to be to use the stock antenna when you need good signal-pulling power and to use a stub if and when you just can't take the RC-model look.

Thanks Gents!

 

I have the Outmotoring stubby and have not noticed any difference throughout the hills and valleys of PA.

 

Thanks Speedwing. I'm going to order the Outmotoring stubby today. We live in a similar landscape so it's probably the best that I am going to get.

 

Also:

coopersport.com - micro antenna ~25
minspeed.net (not minispeed.net)- stubby ~27

 

I don't know if there is anything really special about some of these listed antenni, but I can interchange my 350z/mazda3/s2000/mini antenni. Basically if I were to see a car with a really cool/stubby antenna I'd go to the make's dealership and get it there. Done.

 

I have purchased mine from Mini Mania for both cars,and listen to the stations i like without any problems what so ever.Q

 

I have the craven antenna and there is no noticeable loss in reception, I'm in LA where almost every FM channel is used as a station.

 

I ordered the Ultrik stubby antenna from Mini Mania.

I have some suspicion that these - along with most/all of the stubby antennas being sold, are not actually functional.

If you examine the OEM antenna and base, you will see that there is apparently an insulated center contact. That is, insulated from the screw-in stud.

If you look at the Ultrik, you will see that it is simply a solid piece of aluminum drilled and tapped to accept a stud. (I got the newer one that works on the 07-08 models as well as earlier ones. It comes with two different studs.)

Without seeing a circuit diagram or examining an antenna base off of the car, I can't be absolutely certain. But it appears to me that most of these antennas are just decorative. Screwing it in would SHORT the antenna contacts, and you'd be relying on leakage through the coax cable for reception.

If this is a case, there should be NO difference between using one of these antennas (including those that telescope), and simply sticking a screw in the hole (as some here have done).

There was a very significant degradation vs. the OEM antenna while parked in my (concrete) parking structure. Of course, I expected that, as I didn't expect it to perform as well as the OEM antenna.

BTW, I DO own an ARRL Antenna Handbook, being an ex-ham (lost interest after college and discovering computers) and I've worked for a Bluetooth company as well (writing software, but my curiosity led me to "talk antennas" with one of the hardware guys I know...) so I know a bit about antennas.

Now, has anybody designed a proper active antenna to fit these bases? Or is there already active circuitry in the base? That would be ideal, but I'd think that a stubby helically-wound antenna (like the OEM, but shorter) would certainly do a better job than these decorative bits of metal.

 

My concern, exactly, when I originally started this thread. It looks like we may have to design one ;-)

73 de N1QVE

 

Anyone with experience with the replacement antennas from Moss MINI?
http://www.mossmini.com/Shop/ViewPro...35&SortOrder=3