Truck stop antenna shootout, part 1 and warning

tz1

To do the warning first, the inside antenna connector on my Kyocera card wasn't soldered very well, so after a few insertions (probably less than 20) it broke off. It was covered with the $50 deductible replacement plan (which I am happy I got, they are overnighting a new card). I was suprised as the connector came out and I could see the copper - the pads were large enough, but the surface mount soldering must have been inadequate.

Since I like to drive and listen to internet radio, I was going on the freeway and decided to stop an an AmBest truck stop. I usually look over the tools and various other things, I noticed they had a complete cellular antenna section.

Two were especially interesting. One was a thin magnetic car roof mount with thin coax for $30 (which seemed to work a bit better than the tombstone model but used the same TNC? adapter connector), and another which was larger and used side bars instead of a ground plane with thick coax for some kind of standard truck mount for $10.

I wrote a program that did AT+CSQ? every second so I could try them out.

The bigger and cheaper antenna gave the best signal, around 22/31. The roofmount was in the 20-21 area, so still very good. Sans external antenna, it was around 15-16. The tombstone seemed not to be working very well, but that is when the connector was breaking, so I will report back later after I can retest.

It seemed the card (or tower?) was tuning in over time. It could take 15-45 seconds to come up to full signal strength, but it didn't diminish after it hit unless I did something.

The $10 antenna would be cumbersome (and I've not yet figured out quite how or where to mount it, and those things would increase the cost a bit). But it might be the best value for truly mobile use. (When the KR1 comes out, I can attach it and the antenna to a jumpstart pack). The longer wire also allows it to clear obstructions.

The $30 (probably cheaper elsewhere) is a good compromise, but you still need a groundplane inside, which can be the top of a nearby metal file cabinet. A bit less signal, but a lot less size. (It also might be the coax).

I can't compare it with the booster antenna but will report back when I get a chance.

wankel7 · Posted: Tue Jan 10, 2006 12:00 pm Post subject:

Intresting write up...what are the dimmensions on those two ant. you found?

I am gonna have to swing by a few truck stops!

James

tz1 · Posted: Tue Jan 10, 2006 12:19 pm Post subject:

Smaller one is 12 inches high with a 12 foot RG174U cable (only slightly thicker than the connector to card cable).

Larger one is 33" from bottom to top, but the top 12 inches is the actual antenna with the prongs just below it. There are four 4 inch prongs. The cable is 10 feet of RG-58A/U to the connector. The bottom is a "universal truck antenna mount" which I don't really understand except there was a picture including a spring and a hefty mounting bracket on a truck, however the bottom is a hexagonal shape ending in about 1/2 inch of what is just like a standard coaxial cable (as in cable-tv) connector, so something with the same thread and diamater should accept it.

(there was a $50-$60 model that looked identical to the bigger $10 antenna)

tz1 · Posted: Tue Jan 10, 2006 12:24 pm Post subject:

Continued...

The RG 58A/U cable is about 3/16th in diameter - a lot thicker.

The mag-mount smaller antenna is just a stiff wire with an inductor/spring bend in the bottom and two adjustable collars, but is very light and thin (and has a rare earth magnet in the base).

The larger antenna is about 5/16th in diameter for the rod, but the top portion has a thick cylinder (probably the inductor that does what the spring part does) with the same as the small antenna rod with collar at the top. It included an allen wrench so I could move the collars, except I don't have any equipment or knowledge as to how to adjust it.

tz1 · Posted: Tue Jan 10, 2006 12:48 pm Post subject:

The big one sort of looks like this:

http://alternativewireless.com/cellular-antennas/wilson-antennas/wilson-trucker-antenna.html

Except, it was $9.95, and had four radials instead of three. It may have been a sale or price mistake - if you search the web for the part number the price is around $39.95 (I'll see if I can find the store info from my receipt).

(note the above link also has the mounting stuff).

The one I got (reading from the cardboard back):

Tracker (brand) Truck mount dual band with FME connector

Tracker / 7800 51st Street West / Rock Island, IL / 61201
Model 304-1100, UPC 20126-17700
"will adapt to all current so-239 connectors currently used in most antenna mounting hardware).

---------------

Handy coax calculator page

http://www.ocarc.ca/coax.htm

(the loss on the big antenna is about 1/2 the smaller one, mainly since the cables are both long).

tz1 · Posted: Tue Jan 10, 2006 1:34 pm Post subject: On my VX8100...

I found my antenna adapter for my phone. Some quick results for those interested:

The signal levels are comparable to the Kyocera card.

(AT+CSQ, range is 0 to 31)

Phone on Desk: 14-16

With "booster antenna": 17-18

With (big) trucker antenna: 20-21

I think the booster antenna is rated at 8db and the trucker antenna at 15, so these are probably reasonable.

I don't know quite how these translate into bars, and I don't think it is linear. In any case, size matters, but in two ways. The booster antenna is easy to place around my desk and unobtrusive. The trucker antenna might be a great geek toy on my desk, but isn't very convienient - it isn't going into my laptop case.

Another note on the big trucker antenna - there is probably two more feet of cable between the base and the actual antenna.

RoundSparrow · EVDO User Joined: 12 Aug 2005 Posts: 56

$10 - that is A STEAL! Too bad I don't have a Ambest truck stop nearby. That antenna normally sells for $40.... I looked for the part number on the web.

mwyatt · EVDO Newbie Joined: 21 Dec 2005 Posts: 5

So the "trucker" antennas don't require a signal booster?

I've been looking at getting the Wilson Trucker antenna and their cheaper adapter (357014) for my KPC650 (home setup). Anyone know if this would be sufficient?

tz1

The trucker antennae don't require a signal booster any more or less than the booster antenna, or maybe are somewhere between (but to the booster antenna side).

I checked my receipt - it wasn't AmBest, it was TravelCenters of America, or TA as the logo appears:

http://www.tatravelcenters.com/taweb/home.aspx

It was at the Porter, IN (I94/US20) location. (There is an AmBest there too, and I think I stopped at both).

They are throughout the US. Again, I don't know if the price was a mistake.

The pigtail connector on the card had a problem in that the inner barrel got bent a bit so wouldn't fit (until I bent it back). But that probably lifted the connector slightly so it was misaligned so even beveling the block wouldn't work (mine will fit into either the black or white connector). It also didn't look like it was soldered that well, so if I beveled it too far, it would be more misaligned more often and would have popped off earlier.

tz1 · Posted: Wed Jan 11, 2006 4:35 pm Post subject:

If you go to the link, They have a location finder with PDF and spreadsheet links. I got the antenna at a stop with a "CB Shop", so you might want to see if these are nearby (there are only a few). There are many more stores and they might have it, but the CB/antenna/communications section at this one was huge.

WPSANTENNAS-MATT · Posted: Wed Jan 11, 2006 8:10 pm Post subject:

tz1 · Posted: Thu Jan 12, 2006 1:16 pm Post subject: Part II, now I got my new card.

New card...

The normal signal level might be the 1xRTT which might be a closer but non EVDO tower.

The ARC desktop (carefully placed in an optimal location) works about the same as the trucker antenna pointing up from my cube junction.

With just the card's antenna I get around 55kbps. (two bars on the app)

With either of the others I get around 135kbps. (three bars on the app)

I generally get just slightly higher AT+CSQ numbers with the ARC (14 to 16), but higher with the truck antenna (18-20).

MaximumSignal

dshaffer

Hi, I worked on the KPC650 design. We offer antenna adapter cables with a form fitted overmold on the plug end design to eliminate the forces required to pop the RF connectors off the board.

Can you let me know if your cable had this feature? If not, wrap some tape around the plug to get an interference fit and the problem will be minimized.
_________________
Don

MaximumSignal · Posted: Tue Jan 17, 2006 7:42 pm Post subject: