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11/25 turned VAX?

NeXT

NeXT

Veteran Member
Joined
Oct 22, 2008
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8,149
Location
Kamloops, BC, Canada
I was notified of some VAX gear today.
The majority of it was VAX 4000-700A's (too big useless for my blood) but there were what looked ot be three PDP-11/23's but on closer inspection their system boards consisted of VAX chips and ROMs (marked VAX 4). Was the /23 capable of being turned into a VAX system by a simple boardset swap?
It's a damn shame too. I was close to getting a PDP but I guess I'm still not there. :(
 
Yes, the BA23 case that houses the Micro-11/23 also was used to house microvaxes. So, you should definately grab all of those microvaxes. There are many useful parts in there that will get you most of the way to an 11/23! You may be able to swap parts out of one or two of those microvaxes with some of us here to get you the rest of the way without spending much money.

Lou
 
From what I saw, I have enough parts to make one decent looking system with one of the original SCSI drives.
The SCSI Part boggles me though. These little VAXen and the 4000's all have what appear to be SCSI cards in them but I guess for $25 I can't go wrong. anyways.
I'll pick one up tomorrow and brag tomorrow night. I can do part swaps there and save having to pay $75 for three systems, two of which are jsut for parts.

Edit: what do I need to revert it back to a /23? Just the /23 CPU board and an RX50 controller? The Model number tags on the enclosures state they used to be 11's so I assume the backplanes and power supplies are identical.
 
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The 4000-700A is a damn nice vax! I would want it!

Both VAX and micro PDP-11 use the Q-bus. Early 11/23 used a slightly different Q-bus. But that should not be a problem for you.

For an 11/23. You need: a CPU, a SLU, a BOOT rom and Media with controller supported by the boot rom.

There are CPU-cards with both SLU and BOOT roms on them, but usually you would have them separate. Then you need a controller for the disk you will boot from. It is possible to boot the machine over the serial console with a program called "vtserver" which people have varying success with.
 
I looked at the 4000's and I'm really not too sure about grabbing one. For starters they are rackmount units and secondly they are absolutely massive....and heavy. I think I'll stick with my VAXstation and MicroVAX 2000 systems for now simply because they are a damn lot smaller and I'm still lacking in reall stuff I can do with VAXen anyway so there's no point in getting a system I can barely afford power for.
Are the SLU, BOOT rom, and controller boards uncommon?
 
You definitely need to grab those 4000's They are *really* nice machines. Qbus SCSI cards are RARE and sought after - especially if they will talk to disks (many were tape only). You'll have a lot more fun with the Vax 4000 - nice and fast. Also, they are pretty small as far as vaxen go - one little rackmount box. MUCH smaller than, say, the Vax 6000 series (of which I have four...) I know I've been looking for a 4000 for a long time - they seem to be hard to find.

Look up the numbers on those cards - they might actually by DSSI cards - totally different bus from SCSI, and much cooler. DSSI disks are intelligent. You can even cluster over DSSI.

-Ian
 
I jsut don't have the physical space for one long term. A Vancouver apartment is quite small.

Anyways, I picked up one of the BA enclosures. It had the boards for a MicroVAX 4.
The cards I think were SCSI are CMD Technology CQD-220A/E half wisth boards. I grabbed six of them just in case.

I also spotted som other flip chips:

-Parity module card
- Modem Control scan and MUX card
-three boards from Western peripherals (130002 C, 130003 D, and 130004 A)
-LSI1 Interface card
-SLU/RTC Option (okay, so I got one of the original boards)
-Async Line Interface card
-Printronix PDP-11 controller card

I'll post pictures and more goodies tonight
there were more boards that looked like MASSIVE six connector flip chips (I have only ever seen two and four connector boards) but I didn't grab them. none of them looked like CPU boards though.
There were other random things I only assumed went withother parts that came in but I could not get to them. I'll see if any of it is still around next wednesday when they are open late and I can go in after work.
 
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Well,

Let me be the first to offer you an 11/23+ processor (M8189) in trade for a CDQ-220A if you feel so inclined.

The hex-height cards are Unibus. They could either be from a Unibus VAX or a Unibus 11. I'm sure a number of us here would be interested in the module numbers.

What memory was in the microvax you got? Maybe you can post a list of the M numbers on the card handles. Also, at $25 per unit, you should at least get one more for spares, especially the power supply.

Lou
 
Okay, so I dragged the somewhat reassembled system and a milk crat full of cards back to the lab for some photographs.

The unit:
100_1568.jpg

100_1569.jpg

100_1571.jpg

It looks like an 11/23 though the badge is gone. The RX50 was not present as both bays has SCSI drives in them (they were pulled but I have them set aside so I can DBAN them). Inside was the simple boardset of CPU + Memory and another CQD-220A/E SCSI card.

The boards consisted of:
100_1570.jpg


I have the M7626 CPU board with ROM chips stating it's of MicroVAX 4 origins. There's also two Dataram 63016 32mb(?) memory boards and that SCSI card.
Have not yet powered the system up yet due to it being late but seeing as it came from operating service quite recently, I would assume it still runs.
What I'm unsure about is the back panel. There's the one pictured aboce with the two knobs and DB9 port but it's connected to nothing and in in close proximity to the system when I found it was this...
100_1572.jpg

...which seems to have a connector on the CPU board but does not mount anywhere that I can find.

As for additional SCSI cards. For those who missed out, there are only a handful more however I am being advised to hold off on selling them until my boss and I negotiate a better price (his greed Vs. my willing to see items sell and go to hobbyists who are not deep int he pockets).
 
Slightly OT. I just noticed in the second picture down that there is a little module with two rotary switches. Funny thing is I recognized it. Going to one of my many junk boxes, there was the same unit which I must have picked up at the UBC dump many years ago. It says "FUNCT SEL/SLU MODULE" and it has a three cell rechargeable battery on the back. What does it control?
 
That's the connection for the SLU for the console. The rotary switches are for the baud rate. The one pictured is for a microvax. The one for an 11/23+ and the one for an 11/73 (M8190) look different. I too have one of the microvax ones in my junk box.

The BA23 is the rack mount one and looks to be in very nice shape. The memory is for the vax, and may be too large for an 11/23+ which can only address 2MW of ram. It was well worth $25 though. All that is needed for a nice micro-11/23+ system is a processor with SLU and memory.

Lou
 
Your photos show a standard BA23 box which has now been configured with an M7626 KA660, which is a VAX 4000/200 CPU and the last VAX which connected directly to the Q-Bus. Normally it would be found in a BA213 style box and would be connected to that bulkhead panel which has the MMJ console port and the AUI/BNC Ethernet ports. When mounted as normal in a BA213 box the stubby cable on the bulkhead panel connects directly to the blue connector on the M7626. Looks like someone rigged up an extension cable to attach the bulkhead panel to the M7626.

The other stacked connectors on the M7626 are for the memory cards and the DSSI bus. Only the top three slots in a BA23 are Q22/CD so you can only put the VAX CPU and the VAX memory boards in the top three slots. The CPU and memory boards appear to be cabled together correctly in the photo.

The bulkhead connector with the switches and the DB9 console connector is for M7606 KA630 MicroVAX II, M7620 KA650, or M7625 KA655 CPUs. Maybe the system was first upgraded from an PDP-11/23 to a MicroVAX II, and then later to the 4000/200 CPU. As configured with a KA660 the bulkhead panel with the switches and DB9 console connector would not connect to anything.

If you wanted to configure the system with RX50 or RX33 drives you would need to add an M7555 RQDX3. A cable would connect from the RQDX3 under the bottom of the backplane to the RD/RX distribution panel in the front of the BA23. Then the a cable would connect the RX drive to the RD/RX distribution panel.

-Glen
 
The SEL/SLU module is the VAX version of the console panel used on many different BA23 systems. For the original 11/23, I think it had two DB25 connectors; for the 11/53, a couple of MMT serial ports and for the 11/73-83, a DB9 port and a 2-digit LED for startup diagnostics. All these panels allow external access to the console port with diagnostic display and adjustable baud rate. Very handy.
 
Let me be the SECOND to offer you a CPU card in trade for a SCSI card - though I would offer up an 11/73-83 version. Those CMD cards are definitely sought after - don't leave any behind!
 
Ah, so in technical terms, neither rear console panel is much use on an 11 but recommended to be bundled with the boardset when it's removed and probably sold.
I beleive an SLU card was found in the rest of the boards that I found loose in a box elsewhere.
And for those who are screaming for SCSI (that's probably not a term that has seen much use since the 90's ;) ), I'll see what I can do.
 
Don't be ready to give up the SLU panel too quickly - even though the diagnostic part of the panel won't work for you, the 10 pin serial port can be used with a whole range of other CPUs (the 11/73 for sure, don't know about the 23 or 53) to give you a nice transition connector to a DB9 console connection. I have a very similar system to the one you are assembling - I converted a MicroVAX II in a BA23 to a PDP-11/73 by swapping CPUs and memory. I salvaged the 10-wire ribbon cable from the VAX CPU and plugged it into my 73 CPU. Many other qbus cards also use a 10 pin format for serial output, so being able to go directly to a DB9 and then to a laptop or emulator is very convenient.

The 4 port DB25 set up is also something you can use with several qbus multiport async (mux) cards that carry signals from the card to the connector with wider ribbon cable. A lot of qbus cards don't much care whether the CPU was PDP or VAX.

For now, just be careful about card placement - you'll soon learn the pleasures and perils of serpentine back planes and grant continuity! Quick rule of thumb is to keep the first 3 slots for CPU and memory, leaving the right-hand side of the bus empty if necessary. After the first three rows, you _must_ have cards in both left and right hand pairs of slots.

Bitsavers (www.bitsavers.org) is your friend - I think the BA23 enclosure user's guide does a good job of sorting much of this out.
 
Well this was unexpected.
I returned to pick up the VAX 4000 systems for someone today and I glanced another DEC...something sitting off to the edge of the loading dock.
I thought it to be another unbuyable RA82 but it turned out to be....a PDP-11/84.
So I paid yet another $25 and dragged it home for inspection.

100_1595.jpg

100_1596.jpg

It looks like an air conditioner. You can tell it's fraom near the end of the PDP-11 as it's so minimalistic.

The card listing is wrong. Some cards have either been replaced or removed.
100_1597.jpg

100_1599.jpg

Yes, I know the M9302 terminator is in the wrong slot. I moved it back to the last connector after that picture was taken.

The other thing was that I didn't receive the key. This is VERY frustrating to me because I had a key that was DEC-branded and would of worked that I was given for free by a friend less than a year ago and I lost it. I probably would not of thrown it out but by now it's lost somewhere in one of the many, many boxes of stuff I have from when I moved out of my parents place last May.

Anyways, I found out it was not a regular key so with pliers I got life and I seem to have a successful start!
100_1606.jpg

100_1610.jpg


Now I just need a serial cable for it. Everything I got is at least the wrong gender on one of the sides.
I guess this will be fun for the more expansive projects (adding peripherals as I find them and possibly trading it for something that had more of a front panel) but I'll still like to get the other system converted back as well so I can run it alongside my Rainbow (which also has an RX50 so writing disks is easy for stuff that's not being moved over serial).
 
Awesome. Forget about your 11/23 project now. This 11/84 looks to be in fine shape. As you probably already know, the first few slots are q-bus, then there is an adapter and the rest are unibus. You have the best of both worlds in one chassis.

I don't think that the handwrittten legend of the cards quite matches what is really in there. I am most interested in the two card set that is connected with ribbon cables that is in front of the emulex controller. I think it may be a UDA50 (SDI controller). In which case, you had better go get that RA82 (600MB SDI disk) after all!! (if you do get it, make sure the disk head shipping latch is engaged. The front of an RA8X drive lifts up like the hood of a car when you poke something in the vertical slot in the bottom front. With the hood up, you'll see the big round disk housing with a white plastic knob on top for setting the shipping latch.)

I have a big heavy RA80 connected to my 11/53 (Jack has seen it) and so I don't think an RA82 is really that bad. I have actually been thinking about getting a UDA50 for my 11/04. See, the RA series drives are dual ported, so you can have two computers on line at the same time connected to one drive. Talk about file sharing!

Lou
 
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