The newer generations of SatNavs have much more sensitive receivers - look for SIRF 3 or equivalent. If you want to continue with your old SatNav then you'll probably need an external antenna - lots on eBay, but many do not seem to provide any assistance. Seems silly needing such a thing in a Morgan, but my older Garmin was just the same.

Cheers,

Graham (G4FUJ)

Sold L44FOR 4/4 Giallo Fly
'11 MINI Countryman Cooper D All4
'90 LR 90 SW