On Mon, Jan 23, 2012 at 8:09 PM, Glen Slick <glen.slick at gmail.com> wrote: Really? I'm having lots of trouble finding those for reasonable prices, like those resellers with their standard rate of $700+. Sander -- ~ UNIX is basically a simple operating system, ? ? ? ? ? ?but you have to be a genius to understand its simplicity. ~ dmr

Thanks for the hint! Recently I got a contact of a site still running '11s in Production. I think for CNC-Machines or something like that. Maybe I can get a spare one from there... It's a matter of carefully asking the right person ;) As you stated, this should not be too hard to do. I have a Crimper in my Lab, the connectors should be obtainable and Cable is on stock.

On Jan 23, 2012, at 2:56 PM, Wolfgang Eichberger wrote: In the US, I haven't had much problem finding them on eBay for less than $100. If you get a chance, though, see if you can find a CMD CQD-220; they're an MSCP SCSI adaptor that should work for any OS an RQDX will, but with SCSI disks (i.e. easier to find working disks). Just make sure you don't tell it you have 0 disks and 0 tapes, or I'll have to send you my ROM patch to fix a nasty bug that bricks the board... :-) - Dave

On Mon, Jan 23, 2012 at 11:24 AM, Sander Reiche <sander.reiche at gmail.com> wrote: $700 is rather extreme. A quick search turns up this, which is still not what I would consider a great deal, but 1/10 of that price: DEC M7555 RQDX CTRL http://www.ebay.com/itm/200599388694 $75 - free shipping in US, reasonable shipping listed to Europe

On Jan 23, 2012 11:40 AM, "Wolfgang Eichberger" <oe5ewl at gmail.com> wrote: An H9273 should be a straight Q18 / CD bus so you wouldn't want any dual width cards in the right half of the backplane. With the amount of memory you have installed maybe it was upgraded to a Q22 bus. -Glen

@ david: surely: test under load. its a switcher if i am right. @ dave: i'll contact you tomorrow. maybe we can talk something out.... regards and a nice night. wolfgang -- Wolfgang Eichberger - OE5EWL Operating System Collector Blog: 5ewl.blogspot.com Homepage: www.eichberger.org 2012/1/23 David Riley <fraveydank at gmail.com>

On Jan 23, 2012, at 9:35 PM, Pete Turnbull wrote: I'll vouch for that. My backplane (I don't currently have a box) is an H9273; the designers kindly left proper square wire-wrap posts coming out the back. Updating to 22-bit was a very simple operation with a manual wire-wrap tool, and everything appears to work perfectly. If you do that, make sure you run your wires in the same serpentine pattern as the bus! Probably easiest to do the horizontal runs first and then the verticals to splice them together. Refer to the manual if you're not sure of the pattern, but I seem to recall that I could see the traces (it was a few years ago). I wouldn't recommend soldering, mainly because it'd be a huge pain getting the iron in and it's a lot less reversible. Wire-wrapping it is well worth the time if you have the tools and the wire. - Dave

On Jan 24, 2012, at 3:09 AM, Pete Turnbull wrote: Ah, yes, that's what I mean. Momentary memory lapse, aided by the fact that it's not marked on the thing anywhere I can see. Four slots, right? - Dave

Every BA23 I have uses the first 3 slots as ABCD and the other 5 slots as ABAB in a serpentine manner. If your H973 is the same, then the M8043 (or the dual 256 KB memory board is actually preferred) must be by itself in slot 3. Then, place the next dual board in slot 4 and the next dual board in the other half of slot 4. The M8061 quad board goes into slot 5. (Alternatively, just place the M8061 in slot 3 and run with 3 quad boards at first until you need the other boards.) If you get an M7555 (RQDX3), it will go into the first half of slot 6. Can anyone confirm this for the H9273? If the backplane was ever 18 bit, then it must have been converted to 22 bit since you have 3/4 MB of memory and an 18 bit backplane handles only 1/4 MB of memory. If the distribution panel for the M7555 is present and you decide to get DEC RD5n drives, the cables are standard MFM for the hard drive (20 pin and 34 pin) and just a 50 pin cable standard 34 pin cable with a female header at both ends. The standard front panel has ONE pair of buttons for the hard drive to control READY and WRITE PROTECT and 2 LEDs for the floppy drives to detect WRITE PROTECT on the RX50 floppy media. Do NOT look for an RD53 since 90% have sticky problems unless you get them free and are able to fix them. A Micropolis 1325 can be used, but it requires an extra jumper or zero ohm resistor (R7). Then you will need ZRQB?? to format the drive using XXDP software. The M8189 distribution panel (usually called cabinet kit) handles BOTH serial ports from the M8189. The distribution panel 4 ports. If you initially test with just the first 2 boards (CPU and memory since you don't have any drives yet), then you somehow need to connect the terminal to the serial port on the M8189. However, the correct cabinet kit also sets the baud rate for the consol port. If you don't have that cabinet kit, then you will need someone to help with the cable and the setting of the baud rate. Let us know if you are successful. Jerome Fine

Jerome H. Fine wrote: Oops, so it is. I was half asleep and misread the "256KW" as 256KB", and failed to spot the second memory card at all! -- Pete Peter Turnbull Network Manager University of York

On 01/23/2012 02:09 PM, Glen Slick wrote: Depending on the firmware version the controller will support RX33 format (1.23MB) (TEAC FD55GFR). If only the older firmware you can still use that drive as a single drive RX50. Save for a preserved system any I build from random boards and boxes use the FD55gfr as it more reliable and quieter.. If you do not have BA23 the distribution board out of a BA123 M9058 and cables. FYI the RQDX2 (quad width FDC/HDC) is also usable. Special note early RQDX2s must be in the last unoccupied slot, they do not pass the bus grant signals. Allison