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Author Topic: OK...who here uses a tri-magnet mount????.....  (Read 12986 times)
G7MRV
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« Reply #45 on: August 12, 2012, 09:11:43 AM »

"Oh, and professionals do use mag mounts, as the section of my compalny that intalls emergency services will tell you, there are many reasons why."

So what is the name of your company, what position do you hold in the company and who do you install emergency services for? Name them please.  Smiley

yes, i'd love to breech corporate confidentiality to argue with a nobody on an internet forum. Dream on.


As said, we do use mags for emergency services (although, that term perhaps should be 'law enforcement' for you in the US). Why? well, look at it this way, not every vehicle used is a marked vehicle. Some of them are required to look like a less ominous car. we also diplex broadcast antennas and use special rear heatere elements.  SOmetimes the last thing you want is an obvious permanent antenna mount...
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G7MRV
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« Reply #46 on: August 12, 2012, 09:14:43 AM »

...Oh, and professionals do use mag mounts, as the section of my compalny that intalls emergency services will tell you, there are many reasons why....

Only if there are absolutely no other alternatives.  Here in the states on officer assigned patrol cars, police will sometimes have their own radios or scanners mounted in the car besides their official radios.  You'll see trunk lid clamp antennas much more than you'll see magnetic mounts used simply because those officers KNOW that the magnetic mounts aren't fully reliable.

Professional installers will never put a magmount on a vehicle as a 'permanent' antenna--again unless the customer wants it--and then the installers will try to talk the customer out of using one.

There are other mounting schemes that are much more reliable--and less expensive, both to purchase cost AND removal cost--than magmounted antennas.

Precisely. Unless its a requirement, permanent antennas are used, because we know that mag mounts can fail. There are occasions however when a mag mount is required, because thats the 'normal' type of antyenna used on that type of vehicle, and the law enforcement vehicle has to match. Even then, if at all possible other covert solutions are used. That then prevents any obvious antennas.
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KI4SDY
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« Reply #47 on: August 12, 2012, 01:37:57 PM »

"yes, I would just love to breech corporate confidentiality to argue with a nobody on an internet forum."
I was just trying to determine the value of your opinion. Why would a responsible communications equipment supplier knowingly sell defective antennas to law enforcement agencies? Especially magnetic antennas that "separate" at 60 MPH with a light antenna load. Did you inform the police about that?  Shocked

At least I have provided the official research source supporting my position. Now where is yours (other than personal testimony)?  Wink  

By the way, do you also believe in the Loch Ness Monster?  Grin

« Last Edit: August 12, 2012, 01:45:38 PM by KI4SDY » Logged
G7MRV
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« Reply #48 on: August 13, 2012, 04:19:42 AM »

"yes, I would just love to breech corporate confidentiality to argue with a nobody on an internet forum."
I was just trying to determine the value of your opinion. Why would a responsible communications equipment supplier knowingly sell defective antennas to law enforcement agencies? Especially magnetic antennas that "separate" at 60 MPH with a light antenna load. Did you inform the police about that?  Shocked

At least I have provided the official research source supporting my position. Now where is yours (other than personal testimony)?  Wink  

By the way, do you also believe in the Loch Ness Monster?  Grin



official proof? no, you provided links. Again, your opinion is that you cant see anything says anyone was injured, therefore it cant happen. What a stupid way of thinking.

All you have provided is 'personal testimony' as well, and you could well be anyone. Your whole argument is based on the idea that you think your right, therefore everyone else must be wrong.

Incidentally, do you ever have anything go faulty? or does all your kit continue to work perfectly for ever? Do you live in a hermetically sealed, controlled atmosphere enclosure (sounds like you should)? If not, then like the rest of us, your kit will wear, corrode etc, and perhaps fail. A mount based entirely on magnetic attraction is far more of a risk of failure than one based on physical bonding and forces.

Anyway, as much fun as its been baiting you on here, im bored now. As an aside, visit www.arrse.co.uk to see one of the forums im involved in. You'll see that dealing with self opinionated muppets is a regular sport with us. As they say, never argue with a crazy mind... it might also give you an insight into where some of my knowledge came from

For the rest - simple answer to the original post - use a mag mount only if its your only choice,a nd then be very conservative of the loading. Use a guy line if the antenna is tall, if using a tri-mag, face two towards the direction of travel, and ensure full contact by all the magnets to the steel.
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K1CJS
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« Reply #49 on: August 13, 2012, 04:23:58 AM »

It is not always so simple. Antennas with very high torque loads on mounts like HF antennas can easily distort, bend or fracture thin roof metal in todays cars unless hole is properly gusseted to make it stronger. A tri mag mount spread torque load over a very large area and will hold it better.

It's still a compromise mount--and a cheap alternative to having a mounting done properly.  Permanent installations of larger antennas will have the sheet metal backed up with another metal sheet or plate to reinforce the installation.

Getting back to the original discussion--Magmounts are OK for incidental use.  Just take the proper precautions such as lanyards to prevent unwanted--and unneeded--damages if the magmount were to let go its grip.
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W8JX
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« Reply #50 on: August 13, 2012, 05:58:56 AM »

It is not always so simple. Antennas with very high torque loads on mounts like HF antennas can easily distort, bend or fracture thin roof metal in todays cars unless hole is properly gusseted to make it stronger. A tri mag mount spread torque load over a very large area and will hold it better.

It's still a compromise mount--and a cheap alternative to having a mounting done properly.  Permanent installations of larger antennas will have the sheet metal backed up with another metal sheet or plate to reinforce the installation.

Actually this is not the proper way to gusset. When done properly and  "professionally" the reinforcing metal is secured to base metal via bonding/adhesive, spot welding or rivets not just used as large washers.

Getting back to the original discussion--Magmounts are OK for incidental use.  Just take the proper precautions such as lanyards to prevent unwanted--and unneeded--damages if the magmount were to let go its grip.

Here we go with magic flying antenna again. One more time, IF you use the correct size mag mount for antenna in use you will not have any problems.
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K1CJS
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« Reply #51 on: August 14, 2012, 06:53:32 AM »

...Here we go with magic flying antenna again. One more time, IF you use the correct size mag mount for antenna in use you will not have any problems.

Here we go with the supposed permanent ideal situation again.  Problems that would knock or blow that antenna off can happen.  Why do you think they call it an 'accident?' 
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W8JX
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« Reply #52 on: August 14, 2012, 08:45:07 AM »

...Here we go with magic flying antenna again. One more time, IF you use the correct size mag mount for antenna in use you will not have any problems.

Here we go with the supposed permanent ideal situation again.  Problems that would knock or blow that antenna off can happen.  Why do you think they call it an 'accident?' 

And yet no documentation of another car or person ever being hit or hurt by these "dangerous" missiles. Also a force on a tri mag mount strong enough to unseat it would likely rip the thru roof mount out of roof of a car with todays thin sheet metal.
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K1CJS
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« Reply #53 on: August 14, 2012, 06:24:20 PM »

Geez, a broken record sounds better.
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W8JX
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« Reply #54 on: August 14, 2012, 07:35:46 PM »

Geez, a broken record sounds better.

It must because you keep spinning it.
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K1CJS
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« Reply #55 on: August 16, 2012, 05:10:08 AM »

All right.  I concede.  You can have the last word.  You are just not worth arguing with any further.
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AI4HO
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« Reply #56 on: August 18, 2012, 03:59:30 PM »

I used a tri magnet mount on the roof of my 09 Ford Ranger, had a Tar Heel HP 40A screwdriver antenna attached.  I went from my home here on the east coast of Florida to Dayton, Oh. some times my speeds would be in excess of 80 mph.  Never did come off, even at those speeds, so using one on the trunk of your car shouldn't be a problem.  I don't think you will get the result you expect from a ham stick on a tri magnet mount on the trunk of your car.  If you are bound and determined to use the tri mag mount, put it in the center of the roof of your car.  That way you will have a bit more of a ground plane beneath your antenna. I have since graduated, and now have my Tar Heel on an all aluminium mount attached to the bed of my truck.

I thought that my Tar Heel worked well when it was on the roof of my Ranger..and it did..it worked very well.  When I bought my Tundra a year ago, I knew that I wouldn't be able to put it on the roof.  So I bought the mount and attached it to the bed of my truck..WOW..what a difference it did make. As is very thing in this wonderful hobby..your mileage may vary.  You may do very well with the tri mag on your trunk, but I would seriously consider placing it,(with 2 magnets towards the front) on the roof of your car. Just my incoherent thoughts on the subject.  I hope it works well for you, I do, I wish you the best of luck.

73 de Mark
AI4HO 
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G7DIE
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« Reply #57 on: August 19, 2012, 02:42:13 AM »

Rightly, wrongly, or otherwise, I'm not too fussed by opinion, however my trimag, with High Sierra Sidekick screwdriver, has clocked up around 50,000 miles so far, and no one has been slain by it in that time Wink
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W5DXP
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« Reply #58 on: August 19, 2012, 07:28:07 AM »

... and no one has been slain by it in that time Wink

If it ever happened, a lawyer might present your callsign as prima facie evidence.Smiley
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73, Cecil, www.w5dxp.com
The purpose of an antenna tuner is to increase the current through the radiation resistance at the antenna to the maximum available magnitude resulting in a radiated power of I2(RRAD) from the antenna.
W8JX
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« Reply #59 on: August 19, 2012, 08:58:05 AM »

... and no one has been slain by it in that time Wink

If it ever happened, a lawyer might present your callsign as prima facie evidence.Smiley

You have a much better chance of getting hit by lightening than a flying magnet mount and chances of getting hit by lightening is pretty darn slim.
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