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eHam Forums => Mobile Ham => Topic started by: K9OHI on June 28, 2001, 08:52:21 PM



Title: Operation from ragtop w/fiberglass body
Post by: K9OHI on June 28, 2001, 08:52:21 PM
Has anyone come up with a good way to get decent antenna performance without a good ground plane?  I am operating 2M APRS tracker in my convertible with 5/8 whip on trunk lid which is fiberglass.  Performance is terrible even when running 50 watts.  Have tried setup with same rig/antenna (except used mag mount) on metal body car with lot better success.

On the positive side, GPS rx works great even when sitting on the car seat.  

Love my ragtop, but sure isn't very good for mobiling!

 


Title: Operation from ragtop w/fiberglass body
Post by: PE7JVB on June 30, 2001, 11:25:07 AM
Weird idea maybe but what if you stick aluminium-backed tape,used for insulation etc., and stick this to the inside of the fiberglass trunk lid. Maybe if you try it first on a piece of cardboard too see if it works .I don't know if one layer is enough though. I used this tapes as an antenna on my FM radio when the telescopic one strangly dissappeared. The old valve radio's had them too , on the inside of the wooden casing. And if it works as an antenna it might work as a GP for your antenna too.

Good luck , Jannes PE7JVB


Title: Operation from ragtop w/fiberglass body
Post by: K9OHI on July 01, 2001, 11:48:16 AM
Thanks, Jannes, I'll give it a try.


Title: Operation from ragtop w/fiberglass body
Post by: G8OSN on July 07, 2001, 04:04:34 AM
Hi,

I have fibreglass MPV (or people carrier where I come from) and use a Maldol dual bander (1/2W + 5/8//5/8) which works very well with no ground plane.

I also have a 'rag top' which I plan to build a splitter and automatic switch for so I can share an antenna between the broadcast radio and the Ham gear.
My 'rag top' has a metal body, so I don't have your problem there and plan to use a 1/4W + 5/8 dual bander.

73

Brian
G8OSN