RACAL-DATACOM VA-2450P, VA-2450S, VA-2450G, VA-2450K, VA-2455P, VA-2455S, VA-2455G, VA-2455K Card Type Modem (asynchronous) Chip Set Unidentified Maximum Data Rate 2400bps Data Bus External Data Modulation Protocol Unidentified [Image] CONNECTIONS Function Label Function Label RS-232/422 CN1 Daughterboard header P4 DC power CN2 Daughterboard header P5 Line out CN3 Answer mode switch SW3 Header to main modem J4 Loopback test switch SW4 board Header to main modem J5 board Note: Daughterboard included on VA-2455 models only. USER CONFIGURABLE SETTINGS Setting Label Position Carrier receive level set at 0dBm to -35dBm SWA/1 On (switched-line) Carrier receive level set at -10dBm to SWA/1 Off -45dBm (leased-line) Phase equalization disabled SWA/2 Off Phase equalization enabled SWA/2 On Factory configured - do not alter SWA/3 N/A Factory configured - do not alter SWA/4 N/A Factory configured - do not alter SWB/1 N/A New synchronization pulse generation SWB/2 Off disabled New synchronization pulse generation enabled SWB/2 On Modem uses internal clock source SWB/3 On Modem uses external clock source SWB/3 Off DTR normal SWB/4 Off DTR forced high SWB/4 On USER CONFIGURABLE SETTINGS (CON’T) Setting Label Position Transmit clock separated from receive SWB/5 Off clock Receive clock looped through to transmit SWB/5 On clock DSR forced low when modem is in test mode SWB/6 Off DSR normal when modem is in test mode SWB/6 On RTS normal SWB/7 Off RTS forced high SWB/7 On 50ms delay from carrier signal to raise SWC/1 On DCD 10ms delay from carrier signal to raise SWC/1 Off DCD 275ms delay from answer tone to RTS SWC/2 Off disabled 275ms delay from answer tone to RTS SWC/2 On enabled 160ms delay from CTS to RTS SWC/3 On 7.1ms delay from CTS to RTS SWC/3 Off Local echo disabled SWC/4 Off Local echo enabled SWC/4 On 105ms transmit to receive delay enabled SWC/5 On 105ms transmit to receive delay disabled SWC/5 Off Factory configured - do not alter SWC/6 N/A Modem will pick up the line only when SWC/7 Off handset is off-hook Modem will pick up the line only when SWC/7 On handset is on-hook Factory configured - do not alter JA N/A Factory configured - do not alter JB N/A Modem will disconnect on reversal of line JD Open current Modem will not disconnect on reversal of JD Closed line current Factory configured - do not alter JE Open Signal ground not connected to chassis JF Open ground Signal ground connected to chassis ground JF Closed Factory configured - do not alter JG N/A Factory configured - do not alter JH Open Factory configured - do not alter JI N/A Analog loopback and busy out controls on JJ Closed pins 18 and 25 disabled Analog loopback and busy out controls on JJ Open pins 18 and 25 enabled Pin 18 or 25 controls busy out only JK Open Pin 18 or 25 controls analog loopback JK Closed test and busy out Factory configured - do not alter JL N/A Receive clock follows transmit clock when JM Open no carrier signal is present Receive clock forced high when no carrier JM Closed signal is present SW3 functions enabled JP Closed SW3 functions disabled JP Open Factory configured - do not alter JO N/A Factory configured - do not alter JQ N/A USER CONFIGURABLE SETTINGS (CON’T) Setting Label Position CTS normal JR Open CTS follows RTS JR Closed Auto-answer enabled JS Open Auto-answer disabled JS Closed Signal receive level set at switched-line SW1B/1 On levels Signal receive level set at leased-line SW1B/1 Off levels Secondary channel transmission SW1B/2 Off attenuation set to -5dBm Secondary channel transmission SW1B/2 On attenuation set to 0dBm Secondary channel local echo disabled SW1B/3 On Secondary channel local echo enabled SW1B/3 Off Secondary channel data rate set to 150bps SW1B/4 On Secondary channel data rate set to 75bps SW1B/4 Off Analog loopback test and/or busy out W1 Pins 2 & 3 controlled by pin 25 closed Analog loopback test and/or busy out W1 Pins 1 & 2 controlled by pin 18 closed Hardware configuration is used W2 Pins 2 & 3 closed Factory configuration is used W2 Pins 1 & 2 closed LINE TYPE Setting JC JN Switched line Closed Open 2-wire leased line Closed Closed 4-wire leased line Open Closed TRANSMISSION LEVEL Setting W3 Permissive (-10dBm) Pins 1 & 2 closed Leased-line (0dBm) Pins 2 & 3 closed Programmable Open DIAGNOSTIC LED(S) LED Color Status Condition TXD Red On Modem is transmitting data TXD Red Off Modem is not transmitting data RXD Red On Modem is receiving data RXD Red Off Modem is not receiving data RTS Red On RTS signal is high RTS Red Off RTS signal is low CTS Red On CTS signal is high CTS Red Off CTS signal is low DSR Red On DSR signal is high DSR Red Off DSR signal is low DTR Red On DTR signal is high DTR Red Off DTR signal is low RI Red Blinking Phone is ringing RI Red Off Phone is not ringing CXR Red On Carrier signal detected CXR Red Off Carrier signal not detected MISCELLANEOUS TECHNICAL NOTES The -S and -P models are permissive and programmable switched line modems, respectively. The -G and -K models are 2-wire and 4-wire leased line modems, respectively. The defaults for the jumpers reflect these differences where applicable.