magnet for 102SS whip

[Lost Ram]

Hello CBRT,
Has anyone had any experience with using a quad magnet for a 102" whip? Redman has this one, I am not worried about the coax I can change that. (see below)
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I do not want to put a hole in my Durango and this is not working. (see below)

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I can not get enough counterpoise using this method, the hoop part of the radial element is a 102 whip which is making continuity with the aluminum luggage rack, the rack then has a large gauge ground wire to it coming from the hinge of the rear hatch. I am thinking the quad magnet is a good option. I thought about a Wilson 1000/5000 but I am really partial to a 102" whip. Any help on this one?

[Bombero]

Hey Kerry...

From what I hear from the buddies I have that use this quad mag, it is a PITA when you need to get it off...depending on how strong the magnets are.

[drdx]

That would definitely hold one, and yes they're hard to get off. For positioning one of those, your best bet is to tape cardboard under the magnets until you get it where you want it then remove them.

-drdx

[Lost Ram]

I am really looking for performance opinion or experience.
I have never put a 102" whip on a magnet, do they still perform relatively the same? I assume it would but, I have no personal experience with any magnetic mount antenna. I have only had hard mounted mobile antennas. Does the magnet make the SWR higher or more narrow banded etc.
Heck, does anyone have a clue on how to make the set-up I have now work LOL!!!! I figured I could create a ground plane for it, well I was wrong!! It not like building a di-pole for a base!
Anyway, I think the quad magnet will work, I just wanted a second opinion or three or four. I have a tractor with a bucket and forks, it will come off!

[drdx]

I've used 102 inch whips with mag mounts similar to that with the same success I've had with hard mounts. You may have to run a spring to get the swr down but I've gotten away without one as the whip is very broad banded. The antenna will get its ground via the magnets to the vehicle but some will also run a ground strap(s) to the roof rack bolts or whatever to help in that department. Many will knock the mag mount but I've personally done it and there is a local to me that runs a 1x4 on a mag mounted predator 10k and sounds great- he's done that for years. I'm sure there is some compromize there, and coax routing gets messy as it has to go in somewhere, but the trade of getting the antenna mounted in the best location you can more than pays off. That said, nothing replaces a good hole/puck mount. You can always do the puck, and do it above a map lamp so you can access the bottom withoutt headliner work, and cover it up later with an XM antenna if you have to. Unless that truck is just a couple of years old, save yourself some money and drill away, you'll end up doing it anyway. Once a vehicle is over a few years and 50,000 miles old, that hole isn't going to effect the resale one bit and you'll never be in doubt that you've got the best mount possible.

-drdx

[Lost Ram]

Thanks DRDX!! I figured it would do the job and I do have that large gauge wire already there for an extra ground. This install is not a long term one so I do not want to put a hole in it. If it was not going to work any better then a shorter Wilson 1000/5000 I was just going to get on of those.

[drdx]

If you do the ground, don't use a big wire, use flat braid and keep it as short (as in inches) as possible. On this band when you're talking rf ground, every inch counts and under a foot long strap is what you want, the shorter the better.

-drdx

['Doc]

Why would you want to 'ground' a mag-mount antenna? If you 'need' to, then it's not being used correctly to start with, so do it right to start with.
If you are going to drill a tiny hole for that 'ground', why not just drill a larger hole and 'hard' mount the antenna? It would make no difference in vehicle value no matter how old/new that vehicle is. If you think differently, you're mistaken.
- 'Doc

[Lost Ram]

No holes here doc, I have a wire from the hatch hinge but its not a braided type so it will get removed.

[tim2]

i,ve got two car and truck both work great swrs flat.only problem i,ve had is if u have one a long time moisture gets in between magnut and housing and will rust and lose grd .

['Doc]

This isn't directly related to the topic but I think it's something that really should be thought about. So take it FWIW.

There is absolutely nothing 'magical' or super important about using 'braid' as a ground strap. There are as many disadvantages to it as there are so-called advantages. Braided copper does not stand up well to weather, not to mention the acidic 'stuff' usually found near vehicles/roads. I don't mean it just turning 'green', but being totally eaten up. Tinned braid isn't all that much better than plain braid, primarily because of the added resistance that tinning contributes. Braid does have flexibility, but so does several other types of 'strapping'.
RF ground straps are area dependent. The larger the area of those straps the better till it gets absolutely ridiculous. That surface area does a couple of things, it reduces impedance (AC resistance), is typically flexible, and while it may turn 'green', it usually take much longer to get 'eaten up'.
I had an unbelievable amount of trouble keeping an antenna tuned when using braid ground straps. There was a gradual, not quick, change in tuning. I'd re-tuned the @#$ and it would be fine for a while, but then start to 'loose' it again. (This was on a car bumper type mount, the bumper had to be grounded to the frame, shock absorbers and all that for 'bumping' things.) Finally got tired of the whole mess and had a 'C' plate welded to the frame just in front of the bumper. That 'change' in tuning stopped. Finally reasoned out why, and don't use braid any more, if I can help it. Suit yourself...
- 'Doc