Add an audio delay to your CAT-1000, CAT-700B, CAT-300DXL, CAT-300, CAT-250, or CAT-200B controller. When placed in the receive audio path, the AD-1000 will eliminate the first chirp of DTMF tone during muting and the squelch crash noise present on many repeater systems. The delayed audio is faithfully reproduced. With the addition of an on-board audio gate, the AD-1000 is fully compatible with discriminator audio.