Siretta echo embedded antennae siretta echo1a02mipexss11 the siretta echo 1a is a gsm 3g amp ism tuned pcb antenna with an impressive level of performance across all frequencies despite being extremely compact with a footprint of only 35 x 6mm the echo 1a is perfect for applications where internal space for components is limited or when using an external antenna is simply not appropriate its miniature design allows the antenna to be fixed to the inside of an enclosure or directly