When I had my TE, I extended the receiver antenna, which is just a wire, using a choc block connector. I ran my wire outside my shed. The longer the wire, the better for signal reception.
Do not though attempt to adjust the transmitter antenna. If it is a telescopic aerial, ensure it is fully extended. I swapped my telescopic antenna for the 'rubber duck' style one (with Steve of this parish) which I personally preferred.
For me, this made the transmitter handset more balanced in my hand, and being very long sighted, I was less likely to poke my eye out on the long silver antenna that I found difficult to see....