Dominique, I'm quite interested in seeing your Entrex/Nixdorf system restored. Please keep us updated here. Nice work saving these rare items!
I've done some of my own work restoring a DG Nova-type system. ( http://Point4iris.com ). I'd love to see if there's any way I could help. I'll read Christian Kennedy's response here, as he seems FAR more familiar and knowledgeable than I am here, but if I can add value in any way, I would love to. Best, -AJ On Sat, Apr 1, 2017 at 12:33 PM, Dominique Carlier via cctalk < cctalk@classiccmp.org> wrote: > Hi guys ! > > My name is Dominique, 43 , from Belgium (I apologize in advance for my > approximate English). I join this forum under the recommendations of > Curious Marc. It seems there are people here who can help me to get back to > life the venerable machine that I have just recovered. > > Some pictures of the beast : > > http://www.actingmachines.com/classiccmp_forum/overview01.jpg < > http://www.zeltrax.com/classiccmp_forum/overview01.jpg> > > http://www.actingmachines.com/classiccmp_forum/terminal.jpg < > http://www.zeltrax.com/classiccmp_forum/terminal.jpg> > > http://www.actingmachines.com/classiccmp_forum/comrack_closeup.jpg < > http://www.zeltrax.com/classiccmp_forum/comrack_closeup.jpg> > > It is a "Nixdor 600 series" (Apparently a Nixdorf 620/35), upgraded > several times until 1980, the CPU board is dated from this year. So I do > not know exactly what machine it is today the equivalent. > > Anyway, the Nixdorf 620 is actually built by "Digital Computer Controls" > and after some researches it seems that it is a "DCC-116 E", the 17 slot > version of the "DCC-116" which Is a clone of the "Data General Nova 2/10". > > http://www.actingmachines.com/classiccmp_forum/DCC.jpg < > http://www.zeltrax.com/classiccmp_forum/DCC.jpg> > > The machine has five Key-stations (ENTREX DATA/SCOPE), a Mag-tape Pertec > 8840A - A Disk Cartridge Diablo Model 40 and a big line drum printer (Data > Products model 2230), strange machine, there is a tape reader inside the > printer. > > Here is the list of the boards I have with the references written on them > and their position in the machine: > > *17 HEX 0 – 15 ENTREX INC 62 00 01842 002 REV A* > > *16 HEX 16 30 31 ENTREX INC 62 00 01842 002 REV A** > 15 OPTION 2 Empty** > 14 OPTION 1 Empty** > 13 PRINTER ENTREX INC SN598** > 12 TAPE 556/800 BPI 2433 LFI 213** > 11 TAPE 1600 BPI Empty** > 10 DISK 2456 00 MP-Kontroller D44an620 > 6393500215 2456 7 0 1577** > 09 COMMO Empty** > 08 SCANNER Scanner BD 2431 NCAG 54147.1.15 2431 02394** > 07 MEM 1609 0 7 02616** > 06 MEM Empty** > 05 MEM 1609 0 8 02367** > 04 MEM 1615 01 9 5596** > 03 TTY Empty** > 02 DO NOT USE Empty** > 01 C.P. 1509 05 4 04436* > > Concerning this I also ask a few questions: > > * > > What are the boards in slots 16 and 17 for? > > * > > I do not have a COM card, does that mean that I could not attempt a > serial transmission (type rs232) with this actual setup ? > > * > > I have no idea how many kilobytes are present, apparently there are > two core memory cards (8kb each? 16Kb each?), And non-core RAM board. > > I first solved a problem with the power supply of the disk pack (bad HF > filter, short-circuited with the chassis, then it is also dead HF filter in > the "multi-plug" of the chassis that start to burn, once these problems > were solved, I cleaned the machine thoroughly, cleaning the heads of > readings with isopropyl alcohol, I Not yet cleaned the disc himself which > at first glance looks extremely clean, it has not left the machine for 30 > years. > > http://www.actingmachines.com/classiccmp_forum/disckpack01.jpg < > http://www.zeltrax.com/classiccmp_forum/disckpack01.jpg> > > I cleaned all the guides and the heads of the nine track tape Pertec > 8840A. There was also a false contact in the ON-LINE button. I did a first > cleanup. I think there is always a problem with the HI-DEN button used to > set the magtape to 800BPI. It is currently ineffective, but I have a doubt > about the contacts of the lamp socket). > > http://www.actingmachines.com/classiccmp_forum/ninetrack.jpg < > http://www.zeltrax.com/classiccmp_forum/ninetrack.jpg> > > I then cleaned all the sockets and contacts at the boards of the computer > (logic and PSU) > > http://www.actingmachines.com/classiccmp_forum/clean_contact.jpg < > http://www.zeltrax.com/classiccmp_forum/clean_contact.jpg> > > > Unfortunately, after a couple of hours, the "POWER FAIL" light has started > to light up. The problem here is that I have no schematics, it is a modular > power supply consisting of two elements: > > http://www.actingmachines.com/classiccmp_forum/psus.jpg < > http://www.zeltrax.com/classiccmp_forum/psus.jpg> > > One seems to be dedicated to the 15 VDC regulated, the second module is in > charge of the regulated 5VDC. Both elements have a "Power fail module". > When the machine is completely populated I now observe that the + 5VDC > collapses at +1,9VDC. > > Here what I measured out, you will also see what the boards of these power > supply look like. > > http://www.actingmachines.com/classiccmp_forum/psu_module_1.jpg < > http://www.zeltrax.com/classiccmp_forum/psu_module_1.jpg> > > http://www.actingmachines.com/classiccmp_forum/psu_module_2.jpg < > http://www.zeltrax.com/classiccmp_forum/psu_module_2.jpg> > > Another thing I noted during my measurements, where I should (I think) > measure 15V, I have 18V, looking at the documentation on the NOVA 2 (4 > slots), I observed according to the diagrams below That there is 18V but > before a zener diode and not at the level of connectors where there must be > 15VDC, should I warn me ? Would the diode be dead ? > > I tried to join temporarily a secondary regulated power supply to > reinforce the + 5VDC so as to be sure that the problem did not come from > the logical part of the computer which checks these voltages and triggers > the Power Fail status. By coupling this external regulated power supply, > the computer restarts again, thus it is definitively the power supply (or > the comparator component(s) of the power fail module) > > If I removes all the boards (printer, core memory, scanner, disk > controller, etc.), the Power Fail light eventually goes out, I get again > the 5VDC, so the power has become "too weak" to power the computer when it > is fully populated. > > Despite the temporary (and dangerous) look of my assembly with secondary > power supply, I could not stop myself and attempt a boot procedure via the > Cold Start button of the machine from the Disk Pack, and it works! :-) > > http://www.zeltrax.com/classiccmp_forum/first_boot.jpg > > It seems that I still have problems with the magtape, I had errors trying > to read a backup, but it may be simply because I still cannot get the > machine in 800BPI because of the capricious buttons of the front panel. I > also wrote a tape mark via a "WRITE TAPE MARK AND REWIND" function, the > mark seems to be written but does not do the Rewind, however if I launch a > REWIND only function, it executes the action appropriately. In short, still > things to investigate on this side. > > Notes that the Operating system I used to make these tests is a very > limited OS named DIDOS which was distributed by Nixdorf for his 620 Serie. > As the machine is a clone of DG NOVA 2/10, I wonder if the computer is > compatible with programs for the NOVA series of Data General? So I wonder > if the DCC-116 was compatible with the software for NOVAs? > > The other questions I ask myself at this point are the ways to transfer > softwares or bootable OS on this machine? I have no other disk pack on > another system but I have a nine track tape TU81 + connected to a VAX > 4000-605A under OpenVMS 6.2, and I can put this computer on my network. Do > you think there's a way to make a bootable tape for my NOVA 2 clone with > the Pertec 8840A from a VAX 4000 with a TU81+ ? > > Well, to continue, I have to repair this PSU, all information is welcome, > schematics would be ideal of course. > > Finally, note that I am not a professional electronics technician, I fixed > a lot of machines basic knowledge, intuition, researches, comparisons and > logic, it is effective but full of limitations too, so forgive me in > advance If I do not always understand the possible answers of electronics > in "high engineering" mode ;-) > > As a bonus, the V1 of a small video mounted with a few clips captured > during a session of my nocturnal repairs, during the first boot of the > machine since 3 decades ! (on my music, yes, I'm also a composer ;-) ) > > https://youtu.be/5jWOUtLKRIU > > Thanks a lot to all in advance ;-) > > Dominique > > -- Thanks, AJ Palmgren http://fb.me/SelmaTrainWreck https://www.facebook.com/profile.php?id=100010931314283 https://www.linkedin.com/in/aj-palmgren-4a085516/