Providence Cable Working Group Meeting May 7, 1990 X3T9.2/90-078R0 Date: May 10, 1990 To: Cable Working Group Participants From: Lawrence J. Lamers Subject: May 7, 1990 Cable Working Group Meeting Larry Lamers called the meeting to order at 1:00 p.m., Monday, May 7, 1990. He thanked Peter Blackford of Astro Cable Company for hosting the meeting and he also thanked Nan-Max for arranging the meeting. As is customary, the people attending introduced themselves. The final agenda was as follows: 1. Review of Cable Testing Results 2. Compilation of Cable Testing Results 3. Analysis of Results 4. Connectivity Issues 5. Action Items 6. Next Meeting The following people attended the meeting: Name Organization ------------------------------ ------------------------------ Mr. Denis D. Springer 3M Company Mr. James Fiala 3M Company Mr. Charles Brill AMP, Inc. Mr. Bob Anderson Amphenol Mr. Peter M. Blackford Astro Cable Company Mr. Anthony P. Gabriel Astro Cable Company Mr. Thomas Debiec Belden Wire & Cable Mr. Wills Xu C&M Corp. Mr. Bruce DeBree C&M Corp. Mr. Scott Rasmus C&M Corp. Mr. Joe Spagnuolo Carol Cable Company, Inc. Mr. Scott Allen CMS Mr. Steve Luz CMS Mr. Terry Maezawa Furukawa Electric Amer, Inc. Mr. Brian Griggs Hitachi Cable Manchester Mr. Chuck Grant Madison Cable Corp. Mr. Lawrence J. Lamers Maxtor Corp. Mr. Jim McGrath Molex Inc. Mr. Richard Wagner Montrose Products Company Ms. Marjorie Bacis Montrose Products Company Mr. John Lohmeyer NCR Corp. Mr. Thomas R. Marks NEK/Helix Cable, Inc. Mr. John Emerson Prime Computer Mr. Gene Milligan Seagate Technology Mr. Robert N. Snively Sun Microsystems, Inc. Mr. Kenneth Plourde Tempflex Cable Inc. Mr. D. W. Spence Texas Instruments 27 People Present The following new documents were distributed at the meeting: Document Doc Date Author Description of Document ------------- -------- --------------- --------------------------------------- X3T9.2/90-64 4/19/90 J. Ellis Shielded Cable Evaluation - Digital Rev 1 Near End Crosstalk X3T9.2/90-68 5/4/90 W. Xu External Cable Evaluations - Analog Near End & Far End Crosstalk X3T9.2/90-72 5/4/90 C. Grant Capacitance and Time Delay Testing The results of the meeting 1. Review of Cable Testing Results Berk-tek, Madison Cable, and C&M completed their initial cable testing. John Ellis of Berk-tek was not able to be present, however Larry Lamers presented the results of the testing that he had received from John. Wills Xu gave a brief overview of C&M's analog near-end and far-end crosstalk tests. Chuck Grant explained Madison Cable's capacitance and time delay testing. 2. Compilation of Cable Testing Results The test results were compiled on an overhead to analyze. These results included the test data that Kurt Chan had previously provided. There was a bit of confusion because some of the cables tested were identified with Engineering sample numbers and some with production numbers depending on who got them. The spread sheet with these summarized follows: Cable Identifier: A B E Vendor: Furukawa Madison Madison Part Number: DT-882814 4084 4099 Mean STD Mean STD Mean STD Berk-Tek Digital Crosstalk 2.5 5.7 3.7 .4 .36 .64 C&M Analog FEXT 4.1 3.9 8.2 3.5 3.9 5.3 Analog NEXT 3.1 2.8 1.6 1 Madison Time Delay (ms/ft) 1.542 1.536 1.53 .097 .06 .042 Capacitance 25.3 22.4 19.52 2.75 2.18 2.07 Hewlett Packard Single-Ended TDR 71.3 72.9 82.7 Settling Time 95 93.5 83.5 TERMPWR Voltage 4.135 4.02 3.955 Cable Identifier: F G H Vendor: Belden Montrose C&M Part Number: P1309 SCSI-2 62327 Mean STD Mean STD Mean STD Berk-Tek Digital Crosstalk 3 5.2 5.4 .87 .58 .42 C&M Analog FEXT 4.5 3.9 3.6 4.9 4.1 2.8 Analog NEXT 3.7 10.1 2.1 1.9 1.1 1.2 Madison Time Delay (ms/ft) 1.678 1.365 1.428 .049 .049 .086 Capacitance 23 17.34 17.72 4.4 2 4.26 Hewlett Packard Single-Ended TDR 83.9 85.7 86.6 Settling Time 81 80 75 TERMPWR Voltage 3.785 3.785 3.73 Cable Identifier: I J K Vendor: Astro 28/30 'N' C&M 28 AWG C&M 28/30 AWG Part Number: 52-107B 62286 62523 Mean STD Mean STD Mean STD Berk-Tek Digital Crosstalk 4 5.7 2.7 .9 1.92 .62 C&M Analog FEXT 4.9 4.3 5.6 4.6 5.3 4.9 Analog NEXT 3.4 2.5 2.8 3.7 1.9 1.8 Madison Time Delay (ms/ft) 1.559 1.425 1.475 .052 .079 .093 Capacitance 18.36 17.8 17.65 2.82 3.7 2.59 Hewlett Packard Single-Ended TDR 88.4 91.2 93.5 Settling Time 73.5 68.5 66 TERMPWR Voltage 3.705 3.755 3.495 Cable Identifier: L M Vendor: Furukawa Berk-Tek 28/30 AWG Part Number: DT-891055 270288 Mean STD Mean STD Berk-Tek Digital Crosstalk 4.5 4.2 .58 .83 C&M Analog FEXT 7.4 8.1 4.7 6.8 Analog NEXT 1.8 .9 Madison Time Delay (ms/ft) 1.391 1.409 .053 .197 Capacitance 16.25 15.03 .86 7.09 Hewlett Packard Single-Ended TDR 99.4 108.8 Settling Time 73.5 65 TERMPWR Voltage 3.63 3.85 3. Analysis of Results Bob Snively stated that three cables had passed the Sun system testing, C&M 15030, Madison 4099, and Berk-Tek 48C30. An attempt was made to correlate the parameters of these cables to determine what constituted a good cable. Peter Blackford pointed out that the crosstalk testing did not correlate because no attempt was made to insure that the tested pairs were adjacent. Bob Snively said that the principal failure mode is noise from the data lines coupling into the REQ and ACK signals. In the Sun testing, they tried to maximize the characteristic impedance of the REQ and ACK signals to avoid being near the transition voltage when noise occurred. In doing so, however, they also increased their exposure to crosstalk. He speculated that the best cable construction would be to put REQ and ACK in the center layer, the control signals in the middle layer, and the data line in the outer layer. This construction would best minimize the crosstalk between data and the REQ and ACK signals. Jim Fiala proposed a test that could provide a correlation of crosstalk with capacitance. Measuring the capacitance of each signal pair is significantly easier and less time consuming than measuring the crosstalk of each signal pair. Jim volunteered to check the three cables that passed the systems test and report the results at the next meeting. 4. Connectivity Issues John Lohmeyer raised the issue of connectivity and requested the aid of cable suppliers is finding solutions to the problems inherent in assembly systems using the high-density connectors. An ad-hoc meeting is planned on Tuesday, June 19, 1990 at the Hilton East in Wichita, KS starting at 10:00 a.m. The purpose of this meeting is to get connector, cable, and cable assembly vendors to discuss the cabling needs of systems integrators. 5. Action Items 1) Wills Xu has an action item to re-test the Madison 4099 cable and to test the C&M 15030 cable which had not been previously tested. 2) Larry Lamers has an action item to contact John Ellis of Berk-tek and request a 21 foot sample of Berk-Tek 48C30 cable be sent to Jim Fiala. 3) Wills Xu has an action item to provide Jim Fiala with a 21 foot sample of the C&M 15030 cable. 4) Jim Fiala has an action item to perform a test that will correlate capacitance to cross-talk on the three cables that passed the system test. 6. Next Meeting The next meeting is scheduled for Tuesday, June 19, 1990, at the Hilton East in Wichita, KS. The starting time is 1:30 p.m.