R.F filter for telephone

hi i am radio amateur at 160m. the problem is that when i operate my transmitter the transmitter create interference to the telephone.
i am thinking to put a circuit at telephon's line. My first thought is to put capacitors (10nf) which will ground the r.f. signal what do you think about this. Do you have any better proposition? some one tell me to put one adsl filter.

Make a pi filter with a series inductor and shunt capacitors on both ends. The telephone system operates at a 600 ohm impedance level. Design the filter with a cutoff at 50 kHz or so.