Hello! I was wondering if anyone was familiar with any sources of information on repairing Rana drives? I have a Rana Systems EliteOne on me IIe that just powers up and spins continuously. I'd like to get it going but was surprised to see some manuals out there, but not a lot of people digging into this model, unless I'm just poking around the wrong places..
Thanks!
Pete
If memory serves, the Elite One is more or less a standard drive with 40 track capability.
I seem to think that it might even work on a regular Disk II controller, so there ought not to be too much witchcraft in its logic board.
Have you cracked it open to have a look?
Yeah, it's cracked open alright :) I've gone through and swapped out the socketed chips with known good ones and it doesn't make a difference. I noticed what looks like a missing LED for the index...which then has me guessing everything, but I don't see much in the way of repair photos or videos out there to do some comparisons with a good unit.
Right now I think I need to find some suitable LED to sit in the drive mech (the lower sensor seems to be intact). However, I can't seem to light an LED with the connection, so that has me a bit puzzled. Also, if I put another light source in that position, I would have thought the sensor below the disk would be able to be able to move forward...but that doesn't seem to influence any differences in operation, either.
It essentially powers up, hits the back plate a few times quietly (much quieter than a Disk II) and then just runs endlessly.
Pete
Yes, the Elite One will run fine off a standard DISK II controller card. And the index hole is not used so no need to worry about that. Sounds like the head is not reading (dirty, broken, etc.).
I'm starting to think the same thing.
Check the heads for continuity with an ohm meter.
Also, this thing might be totally out of alignment if it's been in the hands of someone else who didn't know what they were doing.
If that's the case it's not terribly hard to get it back in a serviceable alignment, but let's check the heads first to be sure.
Ok, so there was no upper IR LED or something, above the disk? (There's definitely a sensor below the disk, on the same spot), but from what I can tell, the wiring doesn't actually go to the PCB...it seems to just go to the longer connector (I'm guessing the longer connector is a generic one that was part of the MPI 51SM drive package.
I'll do some digging on checking the heads..not too familiar with that testing but will do some research. I was able to verify the disk was spinning at 300rpm and when I ran i through a MECC diagnostic disk I have, it seemed to think things were ok with secondary test it provided (seems like some sort of data seek test, but interestingly it failed during the first run, then passed the second two runs)...so that coupled with no idea on what it's actually trying to do for that test, I'll keep checking.
Thanks!Pete
So I'm not quite sure what I'm measuring exactly, but the drive head has a 5 pin connector on it
1-Red
2-NotUsed
3-Green/Groundstrap
4-Black
5-White
Resistance measurements look like this:
White-Black 13
White-Green 6.8
White-Red 7.5
Red-Black 7.3
Red-Green 1.2
Black-Green 7.6
That's probably alright - what you'd be looking for is an open coil or a dead short.
One will be the erase coil - probably led to ground. If I had to guess it would be the red lead.
Two of them are the read / write coil.
The symmetry looks good if those colours are what I said they are.
The red to ground is a bit worrying but not sure what its value is meant to be
Yeah, I'm kind of at a loss at what to check next... Nobody unearthed a service manual for these Rana Elite drives? All I see is this really long user manual everywhere :)
I think Sam's Computer Facts have one for Rana disk drives.
Sam’s has them for sale at
https://www.samswebsite.com/m/en/photofact/search/index/brand/RANA
Thanks, I'll check it out!
Just a follow-up for anyone going through a similar scenario. I found the SAMS computerfacts to have good information, BUT the PCB in my EliteOne drive didn't at all match the PCB in the SAMS computerfacts manual scematics/photos.
I ended up getting the drive working by following some of the workings from the Disk II to get the general hardware IC's checked out.
First, the stepper motor was a bit of a siezed mess. First it did nothing, then slowly working with it powered off, I managed to get it loosened up a bit so it would move through half the disk tracks during a format, but would keep going in a different direction once it hit midway, and then start going backwards a couple times before forward, etc. Exercising it a bit more while powered off seeme to fix this. There may be more going on here, but for now I didn't want to disconnect it as it looked like it still had the factory 'adjustment' and I didn't want to touch that. Perhaps exercising this a bit instead of sitting 30 years will help.
Next in the physical tuning department, the track zero start was completely off, which was somewat easy to dial in so somethign would 'happen' at boot (getting some sign of life that it was reading something), but the other main tuning (besides hardware faults) was that the felt pad wasn't pushing down on the disk enough. It wasn't that the pad was worn down too much, there simply wasn't enough pressure. Adjusting the spring arm slightly gave it just a very slight additional pressure to make everything come to life. Otherwise it was hit or miss, it would work for one boot, but not the rest, etc.
I at least have it working to read/write disks that my other drives can also access..but I would love to find a way to tune this in properly. I'm not quite sure how to do that yet, as alignment disks seem a bit of a museum piece at the moment... but we'll see. As fanatical as I am about getting this drive to work, maybe someone is fanatical enough to get a proper alignment disk reproduction going, regardless of what specialized hardware is involved.
Pete
Thanks for the update.
Regarding the stepper - it's probably dry as a bone and needs lubrication.
I would mark it with a scratch awl for rotational posision on the drive, remove it, lube the bearing (it's likely a sintred bronze bearing) and a drop or two of "3-in-1" oil will loosen it up nicely.
Then reinstall it carefully lining up the mark you made.
Nice work getting the head reading correctly.
With regards to fine tuning the alignment, there is a tool that is fairly dangerous to the home user but when used properly will yield very very good results.
That tool is APTEST, and it has a RELATIVE alignment utility that will dial in your drive's alignment against a known-good diskette. That is, a diskette that you are 100% sure was written with a properly aligned drive. Many unprotected commercial software disks will service this putpose - I use Apple's DOS3.3 System Master disk or any other unprotected disk that was written by a mass production commercial duplicator.
Anyway, following APTEST's instructions, included in the utility will usually yield excellent home alignment results with no special tools.