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Monitor cable for the HP 9836

Old Computers

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Does anybody know what the connections for the monitor cable for the HP 9836 (aka: 200 Series Model 36, 9000 Model 236, and 9000/236) are?

I found a reference at one time that said the cable was straight through, but I cannot find it any more and I wanted to make sure that there are no cross-over wires.

Thanks.
 
I made my own cable and now it works. Unfortunately the external HDD/FDD's fault lights up, but I am just happy the monitor works.
 
What are you using for external drives? (specific model)

Are the internal drives working OK? The floppy drives in the units I have had gummed up head rails and had to be cleaned before they would work. They use a very common Tandon TM100-2A.
 
I will have to check to see what the specific model is, but the drive is an HP-IB based hard drive with a 3.5in floppy drive in the same housing.

The hard drive appears to be working. I can hear it spin up and I can hear the heads seeking something during the self test. The first couple of times I heard it spin up it sounded like it faltered a little but I didn't hear that on the third time. After the self test is finished the floppy drive's light stays active, which suggests to me that the fault lies within that drive instead of the hard drive.

I do have a floppy failure for the built in drives. It is the left drive. Before I got the monitor working I removed that drive at one point, moved the read/write head assembly back and forth and it worked for a little while, but now it is gummed up again. I am guessing that the techniques for the PC 5150 drives can be used on this one since they are the same.

Thanks for any help.
 
That is a really cool piece of software. Thanks for pointing it out.

I think I found what drive I have: http://www.hpmuseum.net/display_item.php?hw=286

I can't easily get to the drive to check it right now, but it looks just like this one.

EDIT: I found the service manual, and I believe that the problem lies within the FDD. The service manual does not have a specific condition with the fault LED remaining solid. It did say that it will try a seek test with the floppy drive, and I do not hear that happen. I think that the drive mechanism might be jammed. The disk could be unformatted according to the manual, but I find that somewhat unlikely because the computer reads BAD HARDWARE on the monitor.

I found another service manual and it suggests that the FDD's controller has most likely failed. I hope that the problem is just within the drive mechanism though.
 
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Thanks for pointing that out. So it sounds like if the problem is with the HDD then I am out of luck, but if the problem is with the FDD I might be able to fix it.

Although I am really hoping that the FDD is just frozen. It's not too big of a deal to me to get that drive going, but unfortunately the HP museum only has images of 3.5in media instead of 5.25in media for this system (9836).
 
Thanks for pointing that out. So it sounds like if the problem is with the HDD then I am out of luck, but if the problem is with the FDD I might be able to fix it.

Although I am really hoping that the FDD is just frozen. It's not too big of a deal to me to get that drive going, but unfortunately the HP museum only has images of 3.5in media instead of 5.25in media for this system (9836).

Take a look at the file size of the images from the HP Museum. Even though they are 720K images, the total size taken up on most of the disks is less than 360K. I have a HP 9122D floppy unit that I hooked up to my 9836 and booted from it. I was then able to format floppies on the 360K drives internal to the 9836 and transfer all the files over from the external 9122D.

This could also be done using the HPDrive floppy emulator that gslick referenced in his post.
 
Okay. That is some good news. My only problem is that I do not have an HP-IB interface on a modern computer. Are those hard to obtain cheaply these days?
 
I did a quick look for some of the boards listed as tested and compatible with the HPDrive Emulator.

8-bit ISA and 16-bit ISA boards were selling for $35-$45. (Most PC's with processors running greater than 450Mhz- 500Mhz won't have ISA slots)

The price of PCI boards jumped way up to around $100.

If you keep a close eye on eBay listings, you may find a 9122 drive for less than $100.

Then there is the price of an HP-IB cable to consider if you don't have one.
 
Thanks for checking that. I will definitely keep my eyes open for any of the ISA boards and the drives. (I have a relatively modern system with a 16-bit ISA slot).

I have two HP-IB cables so that will not be a problem.
 
Even though this is an old thread, I thought I would mention the solution I recently found to get the drive working.

I found the proper screwdriver bit that fit the screws for the drive, and I opened it up. A dip switch was misconfigured. One of the switches said floppy/no-floppy. It was set to no floppy. I changed it because my unit has a floppy drive with it. I powered up the drive, and the fault light extinguished after the self-test was finished. The system then booted to a menu that has several BASIC programs to choose from. I am glad that it was a very simple fix.
 
Can anybody in this thread tell me how to get a 9836 open, and how to get the the floppy drives? Mine aren't reading anything, and according to the HP museum, it's likely that the drives' heads are dirty, and that is what's causing the read errors.
 
It is quite easy to open up actually. There are some screws on the bottom of the unit that enable you to take the lid off of the machine. It is very difficult to get the floppy disks out (at least the way I tried it), and I can't remember the exact process I used but it involved taking out some boards from the system to clear the way to remove the floppy drives.

The HP Museum has some documentation, but it does not look like they have a service manual. http://www.hpmuseum.net/display_item.php?hw=3
 
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