HD-4040 Bulletin No: Terminal Node Controller HD-4040-1 Can't Set Demodulator To 1700 HZ Tone Check the 16-pin IC plugs at U30 and U34 for being interchanged. -------------------------------------------------------------------------------------------------------------------- July 5, 1985 HD-4040 Bulletin No: Terminal Node Controller HD-4040-2 Schematic Corrections - R49 And T1 On the schematic in the Hd-4040 Assembly manual [PN 595-3334] and the HD-4040 Blue Book, make the following schematic corrections: Change R49 from a 10 kilohm resistor to a 4700 ohm resistor. At T1 on the yellow schematic, change the transformer part number from 54-1040 to 54-1045. ------------------------------------------------------------------------------------------------------------------ July 19, 1985 HD-4040 Bulletin No: Terminal Node Controller HD-4040-3 "HDLC can't INIT" Error Message Displayed The HDLC will not initialize the HBAUD parameter to either 300 or 400 baud and perm it to NOVRAM. An error message immediately appears on the screen saying "HDLC can't INIT." A temporary solution is to override the firmware by placing the TNC in the transmit mode or by having the TNC identify in CW immediately following the PERM command. This will clear the error message and the TNC will operate properly. Future production should have a firmware change to correct this problem. Because of the low complaint rate [0.1%] and low inventory, an insert won't be put into the finished goods stock. ------------------------------------------------------------------------------------------------------------------- August 30, 1985 HD-4040 Bulletin No: Terminal Node Controller HD-4040-4 Blue Book Correction - Alignment In the HD-4040 Service Data Manual [Blue Book], make the following correction: Alignment, page 8-10, step 6. Change "R33" to "R31". R31 nulls the audio signal at TP1. ----------------------------------------------------------------------------------------------------------------- August 30, 1985 HD-4040 Bulletin No: Terminal Node Controller HD-4040-5 Blue Book Correction - Block Diagram In the HD-4040 Blue Book, Circuit Description, page 5-2, the names of the system bus data line and the system bus contreol line are interchanged on the block diagram. ------------------------------------------------------------------------------------------------------------------ October 25, 1985 HD-4040 Bulletin No: Terminal Node Controller HD-4040-6 Firmware Updated The Version 3.2 code in ROMs U9, U10, U11 and U12 has been updated to Version 3.3. This updated code allows the HDLC to intialize the HBAUD parameter to either 300 or 400 baud and perm it to NOVRAM [SEE Bulletin No: HD-4040-3]. Also, the Version 3.3 code allows 10 retry attempts before disconecting. In future production of the HD-4040, the following ROM changes will occur. U9 from a #444-349-1 to a #444-349-2 U10 from a #444-350-1 to a #444-350-2 U11 from a #444-351-1 to a #444-351-2 U12 from a #444-352-1 to a #444-352-2 If replacement of a ROM is needed, all four ROMs will have to be the same version. -------------------------------------------------------------------------------------------------------------------- December 20, 1985 HD-4040 Bulletin No: Terminal Node Controller HD-4040-7 Blue Book Corrections - Schematic In the HD-4040 Service Date manual [Blue Book], make the following schematic corrections. Change: R49 from 10 kilohm resistor to 4700 ohm resistor. R63 at pin 5 of U20B to read R69. ------------------------------------------------------------------------------------------------------------------- June 13, 1986 HD-4040 Bulletin No: Terminal Node Controller HD-4040-8 Can't Store Data In Optional RAM at U8 With the present firmware used in the TNC, the CPU will not recognize the RAM installed at U8 without special programming. A 4K gap exists between the AM at U7 and the optional RAM at U8. At the present time, this is considerednormal operation. Product Management has been informed of this situation. -------------------------------------------------------------------------------------------------------------------- August 8, 1986 HD-4040 Bulletin No: Terminal Node Controller HD-4040-9 HD-4040 TNC To HW-6502 Interconnect Cable Here's an interconnect cable to use to operate the HD-4040 TNC with the HW-6502 Transceiver: Drawing shows [1] COAX cable, center conductor, from the HW-6502 mic plug to J3 connector of the HD-4040 [pin 5/MIC]. A jumper from the center conductor of this cable to a 4.7K ohm resistor and then to the J3 connector [pin 4/PTT]. Another COAX cable, center conductor, runs from the HW-6502 earphone plug to J3 connector [pin 3/REC]. The shield of this cable runs to J3 [pin 6/GND]. Note: The two coax outer shields are connected together. [[If anyone is in dire need of the drawing before I can scan it in, please let me know and I will send them a copy of it]]. -------------------------------------------------------------------------------------------------------------------- March 31, 1988 HD-4040 Bulletin No: Terminal Node Controller HD-4040-10 HD-4040 TNC To HW-2/XL and HW-4/XL Interconnect Cable Here's an interconnect cable to use to operate the HD-4040 TNC with the HW-2, HW-2XL, HW-4 and HW-4XL Transceivers: Drawing shows [1] COAX cable, center conductor, from the HW-units mic plug to a .1 uF capacitor then to the J3 connector of the HD-4040 [pin 5/MIC]. A jumper from the center conductor of this cable to a 20K ohm resistor and then to the J3 connector [pin 4/PTT]. Another COAX cable, center conductor, runs from the HW-units earphone plug to J3 connector [pin 3/REC]. The shield of this cable runs to J3 [pin 6/GND]. Note: The two coax outer shields are connected together. [[If anyone is in dire need of the drawing before I can scan it in, please let me know and I will send them a copy of it]]. -------------------------------------------------------------------------------------------------------------------- October 27, 1989 HD-4040 Bulletin No: Terminal Node Controller HD-4040-11 Remote Console As A Terminal In order for the HD-4040 TNC to operate properly with the ET-19-2 Remote Console, set the Remote Console's "SCROLL DELAY" to OFF and the BAUD RATE to 300 baud. -------------------------------------------------------------------------------------------------------------------- Thats everything I hold up to 1989 that covers the HD-4040. Enjoy! ------------------------------------------------------------------------------------------------------------------- 73 de Joe W7LPF/4 [NNN0KUU] QWCA - SOWP - NCVA - FISTS - RCC Gordonsville, Va 22942 [Orange Co]