An experiment was conducted to investigate the performance of an electrocardiogram (ECG) telemonitor using mobile internat connections for telemedicine. The RTP/UDP protocol was used for data transmission. Packet loss was observed and an algorithm for error correction was introduced. The experiment showed that the data loss was relative to the packet size. The packet loss was observed by FEC and the interleaving algorithm. Buffer size for interleaving and absorption of network delay was declared. It was concluded that a packet size of 100 bytes is an appropriate choice that realizes about a 3.4% packet loss. The viewing delay is 2 seconds included 1.6s buffer and 0.4s network delay. This was an acceptable performance for practical use in telemedicine and telehealthcare.