Beeline system. Which antenna?

[Rocketman248]

So I just got my HAM license and I'm getting ready to buy a Beeline system. I'm just getting the normal 70cm transmitter. No GPS at this point. For the antenna, I want to get one of the Arrow antennas. My question is, which one should I get? They have 3, 5, and 7 element yagi's.

[troj]

For the antenna, I want to get one of the Arrow antennas. My question is, which one should I get? They have 3, 5, and 7 element yagi's.

Get at least the 5, and I'd recommend the 7 -- the more elements, the narrower the "beam", which means tracking is simplified a bit.

If you get the 7 (it's what I have), get the split-boom. Makes storage and transportation easier.

-Kevin

[sylvie369]

I have split-boom 7-elements as well. They work well. I don't know about the shorter ones - never tried 'em.

[daveyfire]

I have the 5 element, only 'cause thrashing through a corn field with the 7 is a bit awkward. Whenever I've used my friend's 7, I feel very "top heavy". Either one should work well. I'd also recommend getting the attenuator box (or building one); the Beeline works REALLY well and puts out tons of signal, even with it backed off several dB of transmit power, I still get saturation fairly quickly, and having an attenuator is really helpful for getting up close to it.

[n5wd]

So I just got my HAM license

Congratulations! Be sure and let us know what call sign you wind up with.

... I want to get one of the Arrow antennas. My question is, which one should I get? They have 3, 5, and 7 element yagi's.

Well, before I give you MY recommendation, lemme ask a couple of questions, ok?

(1) Do you think that the only thing you're going to be interested in doing with your ham radio license is tracking rockets? Or, can you see yourself taking your little VHF/UHF handie talkie along with you on family trips, campouts, etc? Can you see yourself getting interested in doing any of the public service/community preparation kinda things that a lot of folks are in to?

(2) Would you like to try a little bit of home-brewing before you go out and plunk down the money for an Arrow?

Lemme know the answers to those questions and I can give you a better idea of which antenna I'd recommend. Personally, I use the 2m/435MHz cross yagi (3 elements on 2m (which is where the APRS normally runs) and 7 elements on 435 MHz (though I normally use a frequency in the 446 MHz simplex portion of the band for my Big Red Bee), which is a split boom thingie (like Troj mentioned). I can use all 7 elements if I need the gain, but usually only use the back three (reflector, driven element, 1st director) when I'm tracking a rocket.

Besides the APRS use on 2m and tracking rockets on 446, I originally bought the antenna for use on the low Earth-orbiting communications satellites and used it when we went to Belize a few years ago (you can see a picture of me holding the Arrow and talking though one of the satellites from a dock on a lagoon in Belize , below. Finding out I could use it to track rockets was a plus, just one of those synergistic things that happen in ham radio!

73 Wayne N5WD & good luck, again!




With that antenna, and a little 4 watt HT, the Yaseau FT-503, I talked with 8 different countries, and over 100 QSOs on the UO-14 and AO-27 satellites while we were in Belize.

[Rocketman248]

Sorry, nothing against the HAM guys, but I have no interest in anything other than tracking.

I also don't have the proper tools/skills/patience to properly build an antenna.

I'm most likely going to go with the 7 element split boom. Thanks guys!

[tomar]

Get at least the 5, and I'd recommend the 7 -- the more elements, the narrower the "beam", which means tracking is simplified a bit.

If you get the 7 (it's what I have), get the split-boom. Makes storage and transportation easier.

-Kevin

Get an attenuator for close in work. Once you get within a hundred yards or so it will be very difficult to get any directivity without one.

[n5wd]

I'm most likely going to go with the 7 element split boom.

Yep, then...that'd be the one that probably works best, though you'll probably use the full 7 elements very rarely.

BTW - make sure you get an adapter for your antenna connection if your radio does not use a BNC connector, which comes standard on the Arrow.

G'luck!

By the way... HAM is not capitalized, since it's not an abbreviation for anything. Now that you are one, thought you should know! And, don't worry - you may not plan on it, now, but sooner or later you might find other aspects of amateur radio become part of your interests.

[troj]

Attenuators are nice; they can indeed simplify your life, but with learning a few techniques, you can avoid the need for them.

1) Shield your body with the antenna. If you hold it flat against your chest, and turn your back in the direction of the signal, you'll get little or no signal.

2) Hold the antenna just above the ground and use the ground as an attenuator.

3) Knock your radio off-frequency.

I have an attenuator, I rarely remember to bring it with me. When I do, it does make life a bit easier, but I've done significantly more tracking without one than with one.

BTW, if your radio has an SMA connector, get a BNC-SMA cable; it's easier than messing with adapters. I have both a BNC-BNC cable and a BNC-SMA cable, and prefer not to deal with the adapter.

-Kevin

[Rocketman248]

Thanks for the help guys. I just ordered the Beeline TX and the 7-element antenna. Eventually I'll upgrade to the GPS system. A guy at work knows all about the APRS stuff. He said he'd help me make a base station when I'm ready to upgrade.

BTW, my call sign is KJ4WKG.

[n5wd]

I just ordered the Beeline TX and the 7-element antenna.

Cool! That'll work well for you.

Eventually I'll upgrade to the GPS system. A guy at work knows all about the APRS stuff. He said he'd help me make a base station when I'm ready to upgrade.

See, I told you! Already, you're talking about getting something installed at the house! It's addictive, you'll see!

So what are you going to do for receiving? Something to consider: you ordered a 433MHz transmitter which is good - but unless you're going to order the UHF GPS unit later, most folks go with the 2m APRS GPS unit, so it shows up on the national APRS system (and there are more folks equipped to help track). There's nothing wrong with the UHF GPS Bee, but just consider whether you need a single band (UHF) receiver / talkie, or a dual band (VHF / UHF ).

Ask Troj about his new GPS-equipped Yaseau HT - it's the Cadillac of HTs/trackers right now (until the new Kenwood unit comes out later this year).

BTW, my call sign is KJ4WKG.

Remember, you can always request a vanity call sign to change it if you don't like the sequential call sign.

73 Wayne N5WD

[bigredbee]

Congrats on the new license Nick, your transmitter will ship out tomorrow.

I have to agree with Troj re: the attenuator. Nice, but I, too, have learned to live with out one. One technique to add -- rotate the antenna 90 degrees to change the "polarization" -- that will dramatically reduce the amount signal coming in the the antenna.

I once had to locate my GPS transmitter in a 38mm ebay that had came in all by itself in a field of dense sage -- GPS coords led me to w/in 50 feet or so, but had to locate the signal using just my radio. No antenna, and the body shielding technique that was mentioned did the trick!

Practice...practice....practice....

[troj]

Practice...practice....practice....

...and practice some more.

It's always best to do your first few practices on someone else's rocket.

Find someone in your area who flies a transmitter you can track, and ask if they mind if you track their rocket, too. Then, work on your technique that way. It takes some of the pressure off and lets you get more experience.

Putting your tracker in rockets that are easy to track visually is a good way to get experience, too.

Also, no matter how good the equipment is, it all comes down to technique. Practice and patience will make your life much easier.

-Kevin

[sylvie369]

Of course you can practice without flying a rocket as well. When I first did this with a student group, I had the students practice with the transmitter just sitting on the ground somewhere. By the time we flew the transmitter, the student I had with me was able to walk directly to the rocket without any trouble, even though she'd completely lost sight of it in the air (I saw it land, but I kept my mouth shut).

[daveyfire]

Awesome tips -- hadn't thought of the "turn the antenna 90º" trick before. I'll give that a try this weekend!

[WillMarchant]

Ditto on the "practice practice" advice. You might want to see if your local amateur radio club does "fox hunting" with transmitters. A club member will hide a transmitter somewhere and then every body tries to find it.

http://www.arrl.org/ has a club search engine at http://www.arrl.org/find-a-club

[jcsalem]

I own the 5-element Arrow and have never needed more. While the 7-element is narrower, it's easy enough to triangulate just by moving your position. For the recoveries I've done in the New England woods, the 7-element is just too bulky.

On the other hand, DON'T buy the 3-element Yagi nor their Fox Hunt loop antennas. I tried those first and there was very little directionality to either. Fortunately, the kind folks at Arrow gave me a full refund.

As others have said, PRACTICE IS ESSENTIAL. I had my kids hide my BeeLine. It turned out they hid it under a pile of leaves! Practice at home in a variety of locations -- it will make recovery in the field much more relaxed.

I don't use an attenuator. That gives me one less piece of equipment I need to manage. I can get the same effect just by tuning off-frequency. I use the smallest channel step possible (5kHz on my HT). When I get real close, I remove the antenna entirely and just use the "body blocking" technique described above.

I've never lost a rocket equipped with a BeeLine TX. I've had successful recoveries in the middle of cornfields, tall thorn bushes (ouch!), and under water (the battery died only about 15 seconds after I'd located the general area of the landing). While the GPS version would be cool, I don't think it helps much with the close-in part of the recovery which is often the hardest part here in the heavily wooded northeast.

Jim

[FredA]

We love the beeline.
But the BeeLine GPS is extra cool...and can save the bacon.

At our last launch, one of my team mates flew a BeeLine GPS to about 14k AGL. He didn't use a large enough drogue charge and his rocket came in ballistic until 1000ft where the main poped and tore things apart.
Only nobody saw any of this.
We had packets all the way plus a yagi for direction.
We drove out near the rocket and walked in from the road...to find only the NC and a chute....cut the strap.
The guys walked the "line" back to camp -- over 2 miles of high desert sage -- and came up empty.
I downloaded the GPS data....
Pinpointed the slope change when the strap broke.
Gave the guys that point plus two data points later.
The went to that point and had the lower section within 10 minutes.

Love those Beelines!
FredA

[Rocketman248]

Got the transmitter today. Talk about fast shipping! Now I just have to wait for the radio and the antenna.

I'll be going to a launch this weekend. One of the club members has a Beeline. I'll see if he'll let me practice tracking his rockets. Once I get proficient at it, my G3 gets the J570!