PairGain HLU-319, Manual

Page 1: ...12 10 WARRANTY 13 11 TECHNICAL ASSISTANCE 13 B APPLICATIONS WITHOUT HIGAIN DOUBLERS HDU 451 12 SECTION INTRODUCTION 14 13 POWER CONSUMPTION 14 14 LOOPBACK OPERATION 14 15 TESTING 16 16 SYSTEM MAINTENANCE MENU SCREENS 29 C APPLICATIONS USING HIGAIN DOUBLERS HDU 451 17 DOUBLER DEPLOYMENT RULES 37 18 POWER CONSUMPTION 37 19 LOOPBACK OPERATION 38 20 TESTING 40 21 SYSTEM MAINTENANCE MENU SCREENS 51 Fig...

Page 2: ...the HLU 319 1 04 Revision History of this practice Revision 03 November 6 1996 a Added reference to the HDU 451 List 4 and HDU 439 437 doublers 1 05 HLU 319 List 2D features Selectable DS 1 pre equalizer 130 to 200 Vdc HDSL line power for doubler and HRU 412 Optional bipolar 65 or 100 Vdc or unipolar 130 or 200 Vdc HDSL line power voltage via switch S2 Front panel HDSL S N margin display Compatibl...

Page 3: ...a frame bit 3 03 The HLU 319 List 2D contains a multiplexer that generates two parallel 784 kbps data streams The data streams contain HDSL frames that are nominally 4704 bits 6 milliseconds in length The HDSL frames contain a 14 bit Frame Sync Word FSW 6 bit Cyclic Redundancy Check CRC 21 bit operations channel and DSX 1 payload The DSX 1 stream is separated into two parallel streams that compris...

Page 4: ...zer is programmable to five different lengths as determined by the distance between the HLU 319 List 2D and the DSX 1 interface This provides CB 119 specification compliant pulses at the DSX 1 interface over a range of 0 to 655 feet of ABAM specification cable 3 08 The HLU 319 List 2D contains two separate power converters The main power supply converts 48 Vdc local battery to logic power for the ...

Page 5: ... 319 s Status LED flashes red for the duration of a minor alarm condition Alarms 4 and 5 can be inhibited by selecting None for the ESAL system option see Section 5 for System Settings information The MAL X alarm can be DISabled by setting the margin alarm threshold to 0 The minor alarm can be retired by executing the Alarm CutOff ACO option This is accomplished by pressing the SEL button on the f...

Page 6: ... 232 I O Pin Outs A standard RS 232 DB 9 female connector on the front panel provides access to the menu interface feature via a RS 232 terminal Figure 4 HLU 319 List 2D Card Edge Connectors The active pins are highlighted in black in the above illustration ...

Page 7: ...sing the SEL button for six seconds until the message DFLT NO appears To set the default values press the SEL button while the DFLT NO message is displayed DFLT YES will be displayed indicating the factory default values are now in effect To terminate the Default mode without setting the factory default values press the Mode button or do nothing for 30 seconds The latter returns the display to its...

Page 8: ...ess E to Exit and C to Confirm the changes This activates the new choices and returns control to the Main Menu screen 5 11 The new T1 transceiver chip in the List 2D allows the unit to process both B8ZS and AMI code inputs regardless of the DS1 code setting AMI or B8ZS Earlier units caused input BPV if B8ZS patterns were processed while in the AMI mode When the newer units are in the AMI mode they...

Page 9: ...em to respond to the Teltrend Mod 1 addressable repeater in band loopback codes PWRF DIS Disables powering to the HRU 412 and doubler ENA Enables powering to the HRU 412 and doubler ZBTS ON Tells the HiGain system that the ESF frame is operating in its Zero Byte Time Slot Interface ZBTSI mode OFF Tells the HiGain system that the ESF frame is operating in its normal non ZBTSI mode ESAL 17 Flashes t...

Page 10: ...S signal at both the HLU 319 List 2D and HRU 412 T1 output ports when both of the HDSL loops are not in sync LOSW 1LP Causes the HiGain system to transmit the AIS signal at both the HLU 319 List 2D and HRU 412 T1 output ports when either of the two HDSL loops is not in sync LOSW or if a MARGin alarm occurs SAIS ENA Causes the Lists 6 and 7 HRU 412 to transmit the AIS signal toward the Customer Int...

Page 11: ...DSL line voltage to 65 V on loop 2 and 65 V on loop 1 for non doubler applications Doubler applications will have 100 V on loop 2 and 100 V on loop 1 This setting reduces the maximum ground referenced voltage to 100 V but applies positive voltage to the cable pairs which could accelerate corrosion on the cable pairs 6 04 The line voltage power supply used for both options is ground referenced but ...

Page 12: ...bler Maximum Heat Dissipation 6 Watts without doubler 9 Watts with doubler Fusing Internal connected to Fuse Alarm output on pin 10 HDSL Span Voltage Differential 130 or 200 Vdc Margin Indicator Displays HDSL loop SNR margin for each HDSL loop relative to 10 7 BER operation Electrical Protection Secondary surge protection on DS1 and HDSL ports Power cross protection on HDSL ports Operating Tempera...

Page 13: ...St Santa Ana CA 92705 5101 ATTN Repair and Return Dept 714 832 9922 800 638 0031 11 TECHNICAL ASSISTANCE 11 01 PairGain Technical Assistance is available 24 hours a day 7 days a week by contacting PairGain s Customer Service Engineering group at one of the following numbers Telephone 800 638 0031 714 832 9922 Fax 714 832 9924 During normal business hours 8 00 AM to 5 00 PM Pacific Time Monday thro...

Page 14: ...3 The footprint of a standard 28 slot 23 inch HLU 319 List 2D shelf is 7 024 sq ft Thus the maximum bay dissipation is limited to 840 Watts At 7 Watts per slot this limits the number of occupied slots to 120 per bay 13 04 The thermal loading limitations imposed when using the HLU 319 List 2D in a Controlled Environmental Vault CEV or other enclosures are determined by applying the HLU 319 List 2D ...

Page 15: ...rs A2LB Teltrend Southwestern Bell A3LB Wescom New England Telephone A4LB Wescom Mod 1 New York Telephone A5LB Teltrend Mod 1 Southern New England Telephone SNET 14 06 A5LB differs from A2LB in that A5LB does not block the arming 3 in 5 code from exiting the HLU 319 List 2D into the network A2LB can be configured to either block this arming code after two seconds and replace it with the AIS code o...

Page 16: ...urns the display to normal Note that these same loopbacks can be initiated from the RS 232 maintenance port by choosing the Loopback Mode option D from the Main Menu This displays the Loopback Menu see Figure 11 from which any of the loopbacks can be initiated terminated 15 TESTING 15 01 Table 2 through Table 7 provide step by step test procedures for the HLU 319 List 2D as a function of the loopb...

Page 17: ...124 Revision 03 Page 17 Figure 6 HLU 319 List 2D Non Doubler Loopback Configurations The most important of the HiGain family of loopback options is the Smart Jack loopback which emulates the functions of a standard NID ...

Page 18: ...ormal 4 Have the CO tester send the HLU 319 List 2D 4 in 7 in band loop up code for five seconds Observe that the HLU 319 List 2D displays the NLOC message which indicates that an HLU 319 List 2D loopback is in effect 5 Repeat Step 2 If the test passes the problem is in the cable pair or the HRU 412 If it fails the problem is in the CO equipment 6 The NREM and NLOC loopbacks can also be initiated ...

Page 19: ... in the returned pattern 20 errors if ILR 2 was sent followed by Normal looped data Note This error pattern will repeat every 20 seconds as long as the IOR loopback pattern is being sent This same 20 second repeat scenario also applies to the Time out Override and Query commands It also applies with the appropriate number of bit errors to the other ILR commands The HiGain Line Unit is now in Logic...

Page 20: ...opback 1101 0101 1110 1010 D5EA TIME OUT OVERRIDE Loopback Time out Override 1101 0101 1101 0110 D5D6 FAR END NI ACTIVATE Unblock AIS and pass 2 in 5 1100 0101 0101 0100 C554 IOR POWER DOWN HLU Removes HDSL line power 0110 0111 0110 0111 6767 Note The left most bit arrives first in all sequences The detection algorithm functions reliably with a random 10 3 Bit Error Ratio BER on the facility The I...

Page 21: ...ern 20 errors if ILR 2 was sent followed by Normal looped data Note This error pattern will repeat every 20 seconds as long as the IOR loopback pattern is being sent This same 20 second repeat scenario also applies to the Time out Override and Query commands It also applies with the appropriate number of bit errors to the other ILR commands The HiGain Line Unit is now in Logic Loopback NLOC of Fig...

Page 22: ...pback 1101 0101 1110 1010 D5EA TIME OUT OVERRIDE Loopback Time out Override 1101 0101 1101 0110 D5D6 FAR END NI ACTIVATE Unblock AIS and pass 2 in 5 1100 0101 0101 0100 C554 IOR POWER DOWN HLU Removes HDSL line power 0110 0111 0110 0111 6767 Note The left most bit arrives first in all sequences The detection algorithm functions reliably with a random 10 3 Bit Error Ratio BER on the facility The IO...

Page 23: ...red to execute all the HiGain loopbacks see Figure 6 Note that all code sequences must be present for at least five seconds ABBREVIATIONS USED BELOW LU Loop Up LD Loop Down NI Network Interface CI Customer Interface ESF DL Extended Super Frame Data Link ADDRESSABLE 3 A3LB REPEATER LOOPBACK COMMANDS Position Name Code HLU 319 LU from NI NLOC 1111 1111 0001 1110 FF1E HLU 319 LU from CI CREM 0011 111...

Page 24: ...s the codes required to execute all the HiGain system loopbacks see Figure 6 Note that all code sequences must be present for at least five seconds ABBREVIATIONS USED BELOW LU Loop Up LD Loop Down NI Network Interface CI Customer Interface ESF DL Extended Super Frame Data Link ADDRESSABLE 4 A4LB REPEATER LOOPBACK COMMANDS Position Name Code HLU 319 LU from NI NLOC 1111 1111 0001 1110 FF1E HLU 319 ...

Page 25: ...ame bits occur in the returned pattern 20 errors if ILR 2 was sent followed by Normal looped data Note This error pattern will repeat every 20 seconds as long as the IOR loopback pattern is being sent This same 20 second repeat scenario also applies to the Time out Override and Query commands It also applies with the appropriate number of bit errors to the other ILR commands The HiGain Line Unit i...

Page 26: ...TERNATE QUERY LPBK Alternate Query Loopback 1101 0101 1110 1010 D5EA TIME OUT OVERRIDE Loopback Time out Override 1101 0101 1101 0110 D5D6 IOR POWER DOWN HLU Removes HDSL line power 0110 0111 0110 0111 6767 Note The left most bit arrives first in all sequences The detection algorithm functions reliably with a random 10 3 Bit Error Ratio BER on the facility The IOR Power down code must remain prese...

Page 27: ...d RAIS Remote Alarm Indicating Signal Indicates an AIS all 1 pattern is being transmitted from the remote T1 output port LAIS Local Alarm Indicating Signal Indicates an AIS all 1 pattern is being transmitted from the local T1 output port MAL1 Margin Alarm 1 The margin on HDSL loop 1 has dropped below the threshold 0 to 15 dB set by the user Setting the threshold to 0 inhibits the margin alarm MAL2...

Page 28: ... see Figure 6 initiated from CO network by either the Intelligent Office Repeater IOR code the HLU 319 front panel Manual Loopback push buttons or the maintenance terminal CLOC Customer Local Loopback The loopback at HRU 412 local toward CI see Figure 6 initiated from CPE customer by either the ILR number 2 code the HLU 319 front panel Manual Loopback push buttons or the maintenance terminal CREM ...

Page 29: ...me period Earlier and later data in four hour chunks on six different screens can be accessed by pressing P Previous or N Next respectively All of the counters can be set to zero by pressing C Clear from the HLU 319 List 2D Span Status screen shown in Figure 8 Note that since the HLU 319 List 2D is considered the master module this clears all performance data screens at both the HLU 319 List 2D an...

Page 30: ...dicate out of tolerance components or excessive temperature drift in critical components HDSL 24 Hours ES Errored Seconds The number of 1 second intervals which contained at least 1 HDSL CRC error This value is a running total of the last 24 hours HDSL 24 Hours UAS Unavailable Seconds The number of seconds the HDSL loop was out of sync DS1 BPV Seconds ES The number of seconds in which at least 1 b...

Page 31: ...on loop 1 SIG2 Signal 2 The HLU and HRU transceivers are trying to establish contact with each other on loop 2 ACQ1 Acquisition 1 The HLU and HRU multiplexers are trying to establish synchronization over loop 1 ACQ2 Acquisition 2 The HLU and HRU multiplexers are trying to establish synchronization over loop 2 H1ES HDSL CRC Error Channel 1 HLU HDSL loop 1 CRC error H2ES HDSL CRC Error Channel 2 HLU...

Page 32: ...AMI B8ZS The line code that HLU 319 List 2D is receiving at its DSX 1 interface if the DS1 option is set to Auto Otherwise it mimics either of the other two DS1 line code settings AMI or B8ZS Displayed during System Settings review mode defined above LOSW Loss of Sync Word Indicates that one of the HDSL loops has lost sync Causes a minor alarm LLOS Local Loss of Signal Indicates that no signal is ...

Page 33: ...Section 150 319 124 Revision 03 Page 33 Figure 7 HLU 319 List 2D Main Menu Figure 8 HLU 319 List 2D Non Doubler Status Display ...

Page 34: ...Section 150 319 124 Revision 03 Page 34 Figure 9 HLU 319 List 2D Set Clock Menu Figure 10 HLU 319 List 2D System Settings Menu ...

Page 35: ...Section 150 319 124 Revision 03 Page 35 Figure 11 HLU 319 List 2D Non Doubler Loopback Menu Figure 12 HLU 319 List 2D Non Doubler Performance Data Screen ...

Page 36: ...Section 150 319 124 Revision 03 Page 36 Figure 13 HLU 319 List 2D Non Doubler 7 Day Performance History Screen Figure 14 HLU 319 List 2D Non Doubler Alarm History Screen ...

Page 37: ...greater can 4 The HRU 412 CPE current option must be set to 0 mA Its 60 mA CPE current switch must be set to 0 mA or its card edge pins must be strapped for 0 mA in the enclosure that provides these strapping options 5 In two doubler applications the first doubler the one nearest the HLU can be a List 1 or List 2 The second doubler however must be a List 3 unit 6 In general to optimize doubler per...

Page 38: ...nalysis on a case by case basis 18 06 The maximum Current Drain is the maximum current drawn from the shelf power supply when it is at its minimum voltage 42 5 V It determines the shelf fusing requirements All HLU 319 shelves are partitioned into two equal halves each fused at 10 amps for a total of 20 amps per shelf A fully loaded shelf draws 17 amps worst case 8 5 amps per fuse This is within th...

Page 39: ...ing code from exiting the HLU 319 List 2D into the network A2LB can be configured to either block this arming code after two seconds and replace it with the AIS code or unblock it by executing the Far End Activate code Since A5LB never blocks the arming code from exiting the HLU 319 List 2D it does not need this Far End Activate code A3LB differs from A4LB in that A3LB supports the additional 1 in...

Page 40: ...with the user selected LBTO setting Only one loopback can exist at any given time Pressing both Mode and SEL buttons again for three seconds terminates any active loopback ends the Manual Loopback session and returns the display to normal mode Note that these same loopbacks can be initiated from the RS 232 maintenance port by choosing the Loopback Mode option D from the Main Menu This displays the...

Page 41: ... 319 124 Revision 03 Page 41 Figure 15 HLU 319 Doubler Loopback Configurations The most important of the HiGain family of loopback options is the Smart Jack loopback which emulates the functions of a standard NID ...

Page 42: ...air or the HRU 412 If it fails the problem is in the CO equipment 6 The NREM and NLOC loopbacks can also be initiated from the front panel of the HLU 319 List 2D with the Mode and SEL push buttons see Section C Paragraph 19 10 7 The HLU 319 List 2D can be looped up from the remote location CREM by issuing the 6 in 7 command at the HRU 412 DS1 input port 8 The HRU 412 can be looped up from the remo...

Page 43: ...errors if ILR 1 was sent 200 errors if ILR 20 was sent and 20 errors if ILR 2 was sent followed by Normal looped data Note This error pattern will repeat every 20 seconds as long as the IOR loopback pattern is being sent This same 20 second repeat scenario also applies to the Time out Override and Query commands It also applies with the appropriate number of bit errors to the other ILR commands Th...

Page 44: ... Query Loopback 1101 0101 1101 0101 D5D5 IR ALTERNATE QUERY LPBK Alternate Query Loopback 1101 0101 1110 1010 D5EA TIME OUT OVERRIDE Loopback Time out Override 1101 0101 1101 0110 D5D6 FAR END NI ACTIVATE Unblock AIS and pass 2 in 5 1101 0101 0101 0100 C554 IOR POWER DOWN HLU Removes HDSL line power 0110 0111 0110 0111 6767 Note The left most bit arrives first in all sequences The detection algori...

Page 45: ...errors if ILR 1 was sent 200 errors if ILR 20 was sent and 20 errors if ILR 2 was sent followed by Normal looped data Note This error pattern will repeat every 20 seconds as long as the IOR loopback pattern is being sent This same 20 second repeat scenario also applies to the Time out Override and Query commands It also applies with the appropriate number of bit errors to the other ILR commands Th...

Page 46: ... Query Loopback 1101 0101 1101 0101 D5D5 IR ALTERNATE QUERY LPBK Alternate Query Loopback 1101 0101 1110 1010 D5EA TIME OUT OVERRIDE Loopback Time out Override 1101 0101 1101 0110 D5D6 FAR END NI ACTIVATE Unblock AIS and pass 2 in 5 1101 0101 0101 0100 C554 IOR POWER DOWN HLU Removes HDSL line power 0110 0111 0110 0111 6767 Note The left most bit arrives first in all sequences The detection algori...

Page 47: ...resent for at least five seconds ABBREVIATIONS USED BELOW LU Loop Up LD Loop Down NI Network Interface CI Customer Interface ESF DL Extended Super Frame Data Link ADDRESSABLE 3 A3LB REPEATER LOOPBACK COMMANDS Position Name Code HLU 319 LU from NI NLOC 1111 1111 0001 1110 FF1E HLU 319 LU from CI CREM 0011 1111 0001 1110 3F1E DOUBLER 1 from NI NDU1 1111 1111 0000 0100 FF04 DOUBLER 1 from CI CDU1 001...

Page 48: ...de sequences must be present for at least five seconds ABBREVIATIONS USED BELOW LU Loop Up LD Loop Down NI Network Interface CI Customer Interface ESF DL Extended Super Frame Data Link ADDRESSABLE 4 A4LB REPEATER LOOPBACK COMMANDS Position Name Code HLU 319 LU from NI NLOC 1111 1111 0001 1110 FF1E HLU 319 LU from CI CREM 0011 1111 0001 1110 3F1E DOUBLER 1 from NI NDU1 1111 1111 0000 0100 FF04 DOUB...

Page 49: ...1 was sent 200 errors if ILR 20 was sent and 20 errors if ILR 2 was sent followed by Normal looped data Note This error pattern will repeat every 20 seconds as long as the IOR loopback pattern is being sent This same 20 second repeat scenario also applies to the Time out Override and Query commands It also applies with the appropriate number of bit errors to the other ILR commands The HLU 319 List...

Page 50: ...1 0011 1001 0011 9393 IR QUERY LPBK Query Loopback 1101 0101 1101 0101 D5D5 IR ALTERNATE QUERY LPBK Alternate Query Loopback 1101 0101 1110 1010 D5EA TIME OUT OVERRIDE Loopback Time out Override 1101 0101 1101 0110 D5D6 IOR POWER DOWN HLU Removes HDSL line power 0110 0111 0110 0111 6767 Note The left most bit arrives first in all sequences The detection algorithm functions reliably with a random 1...

Page 51: ...only NLOC NREM CLOC and CREM are available for non doubler applications 21 07 Figure 24 through Figure 27 show the Performance Data screens for doubler applications The Errored Seconds and Unavailable Seconds for both HDSL loops and each T1 input are listed at 15 minute intervals over a four hour time period The Span 1 screen contains data on the two HDSL loops between the HLU 319 List 2D and the ...

Page 52: ...ndicates no alarms LLOS Local Loss of Signal No signal from HLU 319 List 2D local DSX 1 interface RLOS Remote Loss of Signal No signal from HRU 412 remote DS1 interface LOSW1 Loss of Sync Word 1 HDSL loop 1 has lost sync LOSW2 Loss of Sync Word 2 HDSL loop 2 has lost sync H1ES HDSL Loop 1 Errored Second Loop 1 CRCs have exceeded the user selected ES threshold H2ES HDSL Loop 2 Errored Second Loop 2...

Page 53: ...back The loopback at doubler 2 toward network see Figure 15 initiated by either the IOR code the HLU 319 front panel Manual Loopback push buttons or the maintenance terminal CLOC Customer Local Loopback The loopback at HRU 412 local toward CI see Figure 15 initiated from CPE customer by either the ILR number 2 code the HLU 319 front panel Manual Loopback push buttons or the maintenance terminal CR...

Page 54: ... HDSL 24 Hours ES Errored Seconds The number of 1 second intervals which contained at least 1 HDSL CRC error This value is a running total of the last 24 hours HDSL 24 Hours UAS Unavailable Seconds The number of seconds the HDSL loop was out of sync DS1 BPV Seconds ES The number of seconds in which at least 1 BPV was detected on the T1 input DS1 UAS Count The number of seconds during which the T1 ...

Page 55: ... Signal 1 The HLU and the first doubler transceivers are trying to establish contact with each other on loop 1 of span 1 SIG2 Signal 2 The HLU and the first doubler transceivers are trying to establish contact with each other on loop 2 of span 1 S2L1 Signal 2 Loop 1 The first doubler is trying to establish contact with either the HRU or the second doubler transceivers on loop 1 of span 2 S2L2 Sign...

Page 56: ... Intelligent Repeater loop codes ACO Alarm CutOff A minor alarm occurred and was retired to an ACO condition after pressing the SEL button on the HLU front panel SELF TEST Self test The HLU is in a self test mode This occurs every power On Off cycle ALRM Alarm condition exists A minor alarm condition is in effect 1 xx HDSL Loop 1 Margin Indicates the power of the received HDSL signal on loop 1 rel...

Page 57: ...alarm LLOS Local Loss of Signal Indicates that no signal is detected at the DSX 1 input to the HLU Causes a minor alarm RLOS Remote Loss of Signal Indicates that no signal is detected at the DS1 input to the HRU Causes a minor alarm DS1 DS1 BPV Errors Indicates that the number of BPVs at the HLU or HRU T1 inputs have exceeded the 24 hour ES threshold Causes a minor alarm DS0 DS0 Blocked Channels I...

Page 58: ...Section 150 319 124 Revision 03 Page 58 Figure 16 HLU 319 List 2D Main Menu Figure 17 HLU 319 List 2D Status Display Span 1 1 or 2 Doublers ...

Page 59: ...Section 150 319 124 Revision 03 Page 59 Figure 18 HLU 319 List 2D Status Display Span 2 1 Doubler Figure 19 HLU 319 List 2D Status Display Span 2 2 Doublers ...

Page 60: ...Section 150 319 124 Revision 03 Page 60 Figure 20 HLU 319 List 2D Status Display Span 3 2 Doublers Figure 21 HLU 319 List 2D Set Clock Menu ...

Page 61: ...Section 150 319 124 Revision 03 Page 61 Figure 22 HLU 319 List 2D System Settings Menu Figure 23 HLU 319 List 2D Doubler Loopback Menu ...

Page 62: ...Section 150 319 124 Revision 03 Page 62 Figure 24 HLU 319 List 2D Performance Data Screen Span 1 1 or 2 Doublers Figure 25 HLU 319 List 2D Performance Data Screen Span 2 1 Doubler ...

Page 63: ...Section 150 319 124 Revision 03 Page 63 Figure 26 HLU 319 List 2D Performance Data Screen Span 2 2 Doublers Figure 27 HLU 319 List 2D Performance Data Screen Span 3 2 Doublers ...

Page 64: ...Section 150 319 124 Revision 03 Page 64 Figure 28 HLU 319 List 2D 7 Day Performance History Screen Span 1 1 or 2 Doublers Figure 29 HLU 319 List 2D 7 Day Performance History Screen Span 2 1 Doubler ...

Page 65: ...Section 150 319 124 Revision 03 Page 65 Figure 30 HLU 319 List 2D 7 Day Performance History Screen Span 2 2 Doublers Figure 31 HLU 319 List 2D 7 Day Performance History Screen Span 3 2 Doublers ...

Page 66: ...Section 150 319 124 Revision 03 Page 66 Figure 32 HLU 319 List 2D Alarm History Screen Span 1 1 or 2 Doublers Figure 33 HLU 319 List 2D Alarm History Screen Span 2 1 or 2 Doublers ...

Page 67: ...ision 03 Page 67 Figure 34 HLU 319 List 2D Alarm History Screen Span 3 2 Doublers Copyright 1996 PairGain Technologies Inc PairGain is a registered trademark CopperOptics and HiGain are trademarks of PairGain Technologies Inc ...