how to mount a groundplane on a magmount

[nato 2000]

Ive recently made a groundplane for my magmount to use with my tankwhip, just how do you mount it to the magmount/antenna, I guess it cant be touching the antenna as thats made my swr go mental as I guess that effectively lengthens the antenna so it has to be insulated from the metal mount where ive designed mine to fit..

[stampman]

put a mount through the center of the ground plane and mount the tank whip direct on to it

[Dragonfly]

Are the legs steel , If so then just put your magmount in the middle . You might have to make one of those ground plane legs 103 ins long to ballance the SWR . If your groundplane is alluminium then you will have to purhase a 3/8/ mount . http://www.thunderpole.co.uk/fixed-body ... t-kit.html

Here is my magmount on top of the garage .


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[nato 2000]

It's made of aluminium, il get more pics of how ive made it to fit to get my point across as its hard to explain.. But pretty sure ive got it wrong as it shouldnt touch the antenna itself.

[andy@thunderpole.co.uk]

I think the easiest way is as Stampman says, just use a body mount bolted through the middle.

This will then earth out on the ground plane and the tank whip can be screwed into the top of it.

Something like the Snail mount that Dragonfly suggested should work... http://www.thunderpole.co.uk/fixed-body ... t-kit.html

You might need to drill the centre hole out slightly as I think need a 10mm hole, roughly.

Andy

[nato 2000]

This is how ot mounts, sits ontop of the hex magmount part, then the radicals screw and then locate onto thw flats of the magmount and then the antenna is then screwed ontop of it to secure it further.. Now thats the issue Is whether the radials and indeed the 'boss' part mustnt touch the magmount/antenna as it may mess up the swr?

[Dragonfly]

Your Groundplane must go underneath the Magmount not on top of it , It purpose it to increase the size of the magnetic field from the magnet , dont let it touch the Tankwhip antenna . Sometimes you can take the bolt off the bottom of the magnet and bolt the plastic mount to a groundplane .

[nato 2000]

Ok so I will insulate it from touching the whip, but the tristar gp kits mount similar to how ive mounted mine and they work ok?

[andy@thunderpole.co.uk]

The Tristars are not technically ground planes, although everyone calls them that.

They work by changing the radiation pattern of the transmitted signal, and don't do anything to provide a groundplane. It is a common misconception.

A groundplane should always be connected to the 'ground side' of the antenna mounting, therefore making up the bottom half of the complete antenna assembly.

Andy

[Dragonfly]

Here is a Radiator or fridge mount i made for someone in a flat .

[nato 2000]

Cheers for the diagram update dragonfly, clears it up abit, but then mounting it would require drilling a hole in the roof? Not too keen on that which is why ive made this so I can use a Imax 2000 or whatever antenna I choose to be static mobile with.




Took some welding this did! 8mm aluminum.. So I can basically park the car onto the plate, then fit how ever many lengths of pipe into this and then fit the antenna ontop of that... Probably not 100% ideal as the car is directly underneath but I'm sure it wouldnt effect it too much expecially with a proper ground plane on that. Hope you like the handywork!

[Dragonfly]

That is a super antenna stand and will keep your expensive Imax from falling over and getting damaged .
Sorry i was a bit slow on the ground radial u made i didnt realise it was ment as a tristar radial I thought it was for a Loft ground plane , Ive never seen a tristar that big and think it would radiate to much and mess the signal pattern and SWR up .

[stampman]

you could use fishing line as steadiers if it was not too windy

[wildfire]

i have read on forums by uses who are using the tri-star for there antennas & they say that the 3/8 tri-star helps a bit with the SWR but the 3/8 tri-star also helps with the radiation pattern as what Andy has said but in the end of the day it all comes down to what the user would like to use & try

Dragonfly your roof or gutter on your garage would have been much better if the roof or gutter was metal or steel.

[terrym]

Hi Nato 2000

Nice bit of kit you have made there, could you tell me what lengths you made the radials, and what made you make them this length, is there a measurement or calculation you have to use. might try and make one to fit my Sirio 5000 as I have trouble with my ground plane, thought about a tristar mount but not heard any reports on them.