Crap reception?

What we have:
Status omin aerial in our caravan consists signal high/low booster leading to tv/radio sockets (2 of).
Always had crap reception for radio 4 in France with a so called world radio 'er in doors' bought last year.

What I thought of doing:

If I connected a crocodile clip to the signal wire of a length of co-axle cable then clipped the crocodile clip on to the 'Roberts digital' radio's telescopic antena then of course the other end to the radio/tv socket in caravan, would this serve in place of an external/extention aerial socket which many older radio's used to have ?
I don't want to go to the expence of a car radio only to find out it gives the same crap reception.