TLCA Max Antenna Length

[DaveInDenver]

Not necessarily oscillation but the energy imparted into the whip is quite a bit higher when there's 3+ tons of built Land Cruiser doing it.

Think of the way a bull whip works when you accelerate it and then suddenly change directions. The end of that the seemingly light strip of leather actually gets to beyond 700 MPH, the end is breaking the sound barrier momentarily which is the 'snap' you hear. Keep in mind that energy is mass times velocity squared, so speed is critical here. Heck, how much does the end of a snapped towel hurt? What about a 55 grain .223 bullet? That's just 7/100th of a pound, but when you accelerate it to 2,000 ft/sec it has a whole lot of energy.

You've bounced down plenty of trails, you know how jarring an obstacle can be. The sudden changes of direction that your head experiences are not insignificant, now put them 8 feet out on a whip. Getting smacked by an antenna whip is a real thing.

 

[NMC_EXP]

No doubt in my mind regarding the velocity at the tip and the relationship to energy.

What I do not know is how far the tip will swing on a rough trail. When running in timber it catches a lot of low hanging limbs but I never saw the antenna recoil far enough down to come into my field of view. That is what my little test attempted to replicate.

Not being argumentative, just curious. Aside from being indestructible, a 102" steel whip is kind of a pain. I doubt I'll use one again.

 

[DaveInDenver]

I had a 102" whip on the rear bumper of my old Ranger and it was got to swinging so good once it broke out a side window on my camper shell. I haven't run one since although I do still have it. It gets put on top of a mast as a hasty ham radio antenna with a tuner at the base, it's excellent for that. I'd run one again but would figure out a way to tie it down. There are some things you learn and gain experience from, such as this. There are others that you learn the hard way, like people who hook recovery hooks around trailer hitch balls.

 

[mtnbike28]

When I first got my 40 series, I went on a ride with some friends and was running topless, the only antenna I had was a KM40 magnetic whip - 15 minutes in, it was banging all over front/back and side to side. I took it off, tried one more time using a string ties to the windshield frame, same problem. Bought a firestick and never looked back. I know it can break, but hasn't yet....

 

[NMC_EXP]

I always used a large "pot belly" spring used between the 102" whip and base. Never thought about why until now. Starting to think the purpose of the spring is to limit and dampen out whip oscillations.

Could be the 102" whip moves at lot farther w/o the spring and that is how it got its bad rep for reaching out and touching someone.

 

[AlbanyTom]

I put a 102" whip on a 78 Blazer. It worked great. I thought the spring was to keep the antenna from gradually tearing the ball mount out of the sheet metal - and that sheet metal was a lot heavier than any 21st century SUV's. Used a plastic clip to hold the tip of the antenna to the gutter, so I wouldn't knock out bare fluorescent tubes in garages. It would pop out all the time, and hit anything and everything.

My bet is the rule is from someone nearly or actually knocking someone's eye out. They were kinda dangerous. And annoying. But I bet there are way more eye injuries on the trail and campgrounds from those stupid bungee cords than from antennas. Best thing to accidentally kill your vision since spray oven cleaner and those miniature cut-off wheels for dremel tools.

I'm with you guys on the club = rules = suck the life out of things.

With any group, there's always at least one guy that just does dumb things. That guy always seems to run into the guy that either never pays attention, or who is unlucky. And this either leads to some kind of accident, or almost as bad, a near accident in front of the groups "I'm afraid of being sued" guy. That guy then talks to self righteous thinks he's a lawyer guy. Then there are meetings, and the sky is falling, witches are hunted, and lots of rules are drawn up, complete with circles and arrows. And it just goes downhill from there.

The 347th thing I would do if I were in charge, is issue a set of lawn darts to *everyone*. Damn. Now I want to make myself a set.

 

[NMC_EXP]

I'm with you guys on the club = rules = suck the life out of things.

Then there are meetings, and the sky is falling, witches are hunted, and lots of rules are drawn up, complete with circles and arrows. And it just goes downhill from there.

Good one.