Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Sat nav reception

I have been following the thread about where to fix the sat nav. I drilled a couple of holes in the window mounting for Tom Tom and a couple more in the radio cover plate(redundant).
The sat nav is ok there, not ideal but ok.
The problem is that the reception for GPS Signal is not good enough and drops the connection.
Does anyone have this experience? The Tom Tom is a very old Go 300 , do newer versions Have better receivers or do I need to go down the external ancillary route?
Tony