Echo Cancellation Modules
For Asterisk users who connect to the PSTN, echo with the voice communication is possible and can be managed effectively with echo cancellation solutions from Digium. Asterisk itself offers a range of software-based open source echo cancellation routines that are moderately effective in eliminating the echo that most Asterisk users experience. However, there are cases in which these algorithms are not effective. To combat this, Digium offers a line of DSP-based echo cancellation modules for all of our analog and digital (T1/E1/J1) cards with the VPMOCT series modules.
Analog FXS Module Power Supply
FXS modules provide ringing voltage and battery to telephones or handsets and require substantial amount of 12V DC power in order to operate properly. The PCI interface on motherboards cannot provide sufficient quantities of this voltage necessary to ring 4, 8 or 24 modules. As a solution, Digium analog cards are mounted with a 4-pin disk-drive or Molex connector on the base board. This connector must be supplied with an internal power connector from the system's power supply if FXS modules are in use.
Cables and Connectors
Straight-through and cross-over cables for connecting Digium T1/E1 interface cards and T1/E1 ports, telephone cables for interfacing analog cards, and timing cables for digital cards.
Low Profile Brackets
Digium Telephony boards come standard with full-height brackets for standard mounting. Optional low-profile brackets are available for all low-profile cards to enable mounting into 1-U servers.