(29 July 2012, 21:32)Lightspeed Wrote: (29 July 2012, 20:37)NorthernRaider Wrote: (29 July 2012, 19:42)Paul Wrote: If this is your only vehicle and it has a boot, why not fit a boot lip mount instead.
No holes to drill, and it doesn't mark the paint work (on the outside anyway).
cos its a Transit van and has no boot 
You can get mobile cables with what is called a pig tail. This is a very thin 1/8th" ? short length of coax that passes from the antenna through and across the door seal. Its quite flexible and being thin is less cruched when the door is closed.
Are such cable available for CB Paul or are they only available from ham shops?
No, too faddy for CB'ers let alone PMR installers. Pigtails weren't generally used by us when I was a PMR and cell phone installer as they tended to cause more problems than they solved.
THe addition of either thin coax, Bi strip, or the older oval types of tails can muck up your SWR as well as introduce losses through the extra connectors (be that SO or PL259, RCA, UHF sub min, or TNC).
Granted it's not a lot but typically minus 0.5 db per foot of pigtail.
Add typical losses of .05 db for a radio connector times two and you've potentially lost 0.6 of a watt out of your 4 with a street legal CB.
Thats 15% of your power.
Additionally, the higher the frequency the more the transmission loss.
800 Mhz plus was a nightmare to fit bespoke cellular wiring in unusual vehicles. The losses were brutal when using pigtails. Better to just take the hit and occasionly change a chewed coax.
Boot lip and hatch back mounts on cars aren't terribly complicated things as are the car rubber seals. THe only time I've had problems was with high end cars.
Vans, never. Their door seals are "generous" to say the least.
With those I used gutter or mag mounts as standard. PMR and CB aerials were usually mounted on twist off mountings and the mag mount stayed put on the top of the van.
I also used to fit taxi aerials on magmounts. It's all in the fitting where you angle the coax and tywrap it to the rubbers.
Again only on high end cars did I ever see chewed coax. .
Those we sleeved the coax with 6mm ID pvc pipe at the point where the cable ran through the door seal.
THe main problem we had was removal of the magmounts at night when the drivers would just chuck them into the car. Broken coax at the mag mount was the common fault.
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