_ FCO DF224-R001, Modem won't answer phone, garbage generated ----------------------------------------------------------------------------| | _ _ _ _ _ _ _ | | | | | | | | | | Level of Page 1 | | |d|i|g|i|t|a|l| Urgency Of 4 | | |_|_|_|_|_|_|_| FCO [ R ] | |___________________________________________________________________________| | FIELD CHANGE ORDER Number: DF224-R001 | |___________________________________________________________________________| | Applicability: Replace the DF224 Module Revision "A" with Revision "B1" or| | later when Problem/Symptoms are evident. | | | | Phase-in the DF224 Modem Module (P/N 29-25042-00) Revision "B1" (ECO #21) | | as the minimum acceptable Revision for incoming stock. Purge SR17, Field | | SR's and CD kits of all stock that has no Revision Identification | | (Revision "A"). | |___________________________________________________________________________| | Problem/Symptoms: | | 1) On some PBX's, the modem will not answer the phone. 2) Random garbage | | can be generated when editing keys are used, or a string of "U" can appear| | on the terminal or added to system data. 3) Modem will not recognize the | | dial tone from some older Phone Systems. 4) When auto-dialing, the DF224 | | intermittently appears to not recognize the remote modem's answer back | | tone. | |___________________________________________________________________________| | Quick Check: The module will be marked with CS Revision "B1". | | | |___________________________________________________________________________| | Compatibility/Prerequisite FCO: | Est. Time to Install | | None | 0.5 Hours | |___________________________________________________|_______________________| | Special Tools or Test Equipment: | | If possible, refer to the documentation supplied with the modem. The | | Installation Guide P/N is EK-DF224-IG-001. | |___________________________________________________________________________| | FCO Parts Information | |___________________________________________________________________________| | Order by | Contents | | FCO Kit # |____________________________________________________________| | | Quantity Part Number Description | | | | | EQ-01377-01 | 1 29-25042-00 DF224 Modem Module | | | 1 FA-04659-01 FCO Document | | | | | | | |______________|____________________________________________________________| | EQ Kit Variation/System-Option Applic: N/A | |___________________________________________________________________________| | Approvals | |___________________________________________________________________________| | CSSE Engineer |F.S. Product Safety | F.S. Logistics | | Bryan Williams | John Freudenberg | Edward Duggan | |________________________|_________________________|________________________| | Responsible CSSE Mgr |F.S. Microfiche Libraries| Affected Population | | Tony Payne | | 400 | |________________________| PDP-11 |_______________________ | | ESD&P Micropublishing | LCG | Initial Kitting | | Barbara Eriss | | 100 | |________________________| VAXnotes |_______________________ | | Revision | STARS | Hardcopy Publication | | A | | 500 | |________________________| |________________________| | FCO Release Date | | Parts Availability | | 17 October 1985 | | November 1985 | +---------------------------------------------------------------------------+ _ _ _ _ _ _ _ | FCO DF224-R-001 | | | | | | | | | |d|i|g|i|t|a|l| | PAGE 2 OF 4 |_|_|_|_|_|_|_| | | _______________________________|_________________________________________ INSTALLATION PROCEDURE FOR DF224-R-001 The following procedure is extracted from the DF224 Installation Guide (EK-DF224-IG-001). Refer to this manual for clarifications. Call the Atlanta Hotline if support is needed. 1. Remove power to the unit by unplugging the wall power supply from the outlet. 2. Unplug the power supply from the modem module. 3. Unplug the DTE (Computer or Terminal) cable from the modem. 4. Unplug the Phone Line and the Telephone. ****************************************************************************** * NOTE * * * * If the customer has changed any switch settings, or changed the * * default set-ups, you/he may need to change the switches or options * * on the new module (between steps 4 and 5). * * * ****************************************************************************** 5. Set the old modem aside. 6. Take the new modem module and plug in the power supply. 7. Plug the power supply into the wall outlet. Insure that the LL light comes on, then goes off after a few seconds. The SI light should come on. 8. Reconnect the phone line to the jack labeled "Phone Line". 9. Reconnect the Telephone set (if any) to the jack labeled "Telephone Set". 10. Reconnect the DTE cable (from the terminal or computer). 11. Fill out LARS as shown in the attached example. _ _ _ _ _ _ _ | FCO DF224-R-001 | | | | | | | | | |d|i|g|i|t|a|l| | PAGE 3 OF 4 |_|_|_|_|_|_|_| | | _______________________________|_________________________________________ PLEASE PASS THE FOLLOWING INFORMATION ON TO YOUR CUSTOMER: Symptom: 1) User gets "No Dial Tone" message even though there is dial tone on the line, and the modem is connected properly. 2) When auto-dialing, the DF224 appears not to recognize the remote modem's answerback tone. Problem: 1) Some older Central Office Exchanges use dial tones that are not in compliance with Bell Specification. The modem does not recognize those older dial tones. 2) The DF224 looks for the "ringback tone" before it looks for an answerback tone. If the remote modem answers the phone before the remote PBX is able to generate the "ringback tone", the DF224 will never get to the point of looking for the answerback tone. Solution: 1) Since changing the product to recognize older dial tones would involve massive hardware changes, Digital has modified the way that the wait character ("W") is implemented. The end result is a process called "Blind Dialing" where the modem will wait for 5 seconds, then dial the number, regardless of whether or not dial tone was detected. 2) Since changing the product to look for just an answerback tone would seriously deter the call progress features from functioning, Digital further modified the W character such that when used in a Blind Dialing Mode, the DF224 does not look for the "ringback tone". To use this new feature, place the W character at the beginning of the dialing string. For example (refer to the Owners Manual for an explanation of the other characters): WP2641035! The changes necessary for this to function have been implemented with this FCO. \^ DF224 \\DF224 \\WILLIAMS \\1985 \\OCT \\FCO_DOCS