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[ghondie]

hi all, do any of you know if there is a technical buliten available that shows manufacturer recommended positions for mounting aerials and power/antenna cables for a PMR radio? im pretty sure most manufacturers have them?

Regards
Nathan

[Dave DND]

I thought that the golden rule was to keep the antenna as centrally mounted within the groundplane as possible to ensure even coverage.

What are you fitting this to?

There are technical bulletins etc available from the PMR manufacturers, but unlikely to cover very old cars such as Omegas.

[ghondie]

this will be going on my omega, i was thinking more about any computer related cables that i should be avoiding, im gunna run the power cable down the left side kick well to the boot where i will put the main radio unit, the remote head mic and speaker signal cables i will run back down the side well . the antenna should not be a problem as it will be contained to the boot.

the main thing im woried about is the airbag ecu. as im not sure where thats located.

Regards
Nathan

[Dave DND]

Personally wouldn`t worry about the airbag ECU -

PMR`s have come a long way, and both they and ecu`s are very well shielded these days.

 

[Kevin Wood]

Panorama do some nice PMR / Amateur antennas that you can mount in the hole occupied by the existing mobile phone "bee sting" to the rear of the roof.

See the posts towards the end of this thread: http://www.omegaowners.com/forum/YaBB.pl?num=1229127041/3

I mounted the radio in the rear "cubby hole" on the opposite side of the boot to the spare wheel (saloon).

Run a separate fused cable from the battery positive terminal to the radio, as you would for an audio amp, ground the radio to the vehicle body close to the radio and make sure the antenna is making a good ground connection to the roof.

For good measure pass the connections to the radio through some split ferrite cores or wind a couple of turns on a toroid to keep any RF off the wiring through the car.

As Dave said, I would imagine most electronic systems in a car (especially airbags) are engineered to cope with high radio field strengths. I have certainly seen no issues at power levels up to 40 watts.

Kevin

[Dave DND]

There were a few scary stories in recent years with Airbags and PMR`s, both centered around Mercedes and Ford vehicles primarily.

The cause of the problems appeared to be from those using glass mounted aerials, but no self respected PMR user would use anything other than a body mount aerial drilled and grounded correctly.

 

[zirk]

hi all, do any of you know if there is a technical buliten available that shows manufacturer recommended positions for mounting aerials and power/antenna cables for a PMR radio? im pretty sure most manufacturers have them?

Regards
Nathan

MPT1362 (Code of Practice) is the document your probally looking for, can be downloaded from the Goverments RA Dept or Ofcom.  

[ghondie]

There were a few scary stories in recent years with Airbags and PMR`s, both centered around Mercedes and Ford vehicles primarily.

The cause of the problems appeared to be from those using glass mounted aerials, but no self respected PMR user would use anything other than a body mount aerial drilled and grounded correctly.

 

exactly, dont see why anybody would want to use a glass mount, even a boot mount is better than nothing. i will probably put one on the roof in the existing hole as suggested, and then have one on eac side rear quaters, guess i could put them on the top but would rather not be drivlling holes in the roof and playing with linings.

Mainly this is for ham use, but also other things as well.

i do like the look of the combined gps/vhf and mobile phone antenna. could be handy to have it all plumbed in still.

Regards
Nathan

[VXL V6]

One thing to check while trying to centre the antenna (more equal ground plane the better) is to just check how far the sunroof goes back!!!!

[ghondie]

One thing to check while trying to centre the antenna (more equal ground plane the better) is to just check how far the sunroof goes back!!!!

luckily or unluckily(depends how you look at it) i dont have one of those most modern of devices in my car.
now i have come to the dilema, where to mount the remote head, i think i may remove the ashtray bit as i dont use it anyway, plus it will give me a good position away from the middle of the console, i have quickly eyed it up with the gear stick as well, seems like a good place to put it. also then it means i can hide the wires into the dashf or a nice neat install. now to find some black plastic or similar to make a plate to cover around the sides of the head and make it look better.