Combined VHF/GPS Antenna #2

[Rob_Brookes]

Way back in the mists of time I posted information about through-body combined VHF and GPS antenna for vehicles. This time it's a magnetic mount version aimed more at team members private cars than at team vehicles. These are usually Landrovers and are mostly aluminium so a magnetic mount isn't a lot of use. On your own car however, this is a very neat option if you have GPS tracking added to your own vehicle radio.

This particular one is made by Panorama although I'm sure there are others.

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The whip section is flexible and plastic coated although you can have a rigid steel section if you prefer.
When described as 'flexible' it most certainly is but it stays largely upright at legal speeds and there's no noticable difference in performance between this and a 'standard' rigid-whip magnetic mount antenna. In fact this antenna actually appears to perform slightly better than the last mag mount I used.

The magnet is man enough for the job and an anti-scratch rubber boot is provided. Not only does it not detatch at normal speeds but judging from the dust and salt on the roof of our car, it doesn't move from where it was originally stuck either.

The supplied cable is thinner than the normal URM76 you get with mag mount antenna and is a figure of eight twin style as it also has a cable for the GPS antenna that's built into the magnetic mount.

I did wonder about this initially as crushing your antenna cable in a car door is a sure fire way of ruining its performance and this wouldn't take much crushing. However in practice, being thinner, it actually fits between the door and the rubber door-seals much better than conventionally sized cable does and after many months of use and much boot-slamming, it's come to no harm and continues to work fine. The connections required by a Simoco SRM9000 with an MA-ASIGF GPS board fitted, are already on the cables and it's literally a five minute job to fit it.

This type of antenna has now been in use by myself and the team leadership of Langdale Ambleside MRT for several months and has given faultless performance so far. The whip section is an easily replaced part should it ever come adrift but none have as yet.

I have no idea whether the performance of the GPS element is any better than that of the patch antenna that comes with the GPS accessory boards but for the convenience of having it all in the one place on the roof and technically only having to feed a single cable into the car, it's worth a look.