Recently got a 1000 RLX-HD unit with a bad 3.5" floppy drive. I've replaced the caps. It goes through all of the motions but does not read a disk. The head was cleaned with q-tip. I'm at a loss as to what can be done. This is one of those 3.5" drives with the power on the cable. Not sure how I am going to be able to fix or replace the drive to get data on the computer. Any suggestions greatly appreciated.
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Tandy 1000 RLX-HD 3.5" Floppy Drive Not working
- Thread starter Tim-Wolf
- Start date
I was able to take the heads from a working Teac FD235 other than a 105-U and transplant the heads. This resulted in being able to fully FORMAT, and WRITE data from the Tandy to a new disk. However, it will not read any other disks. When I put it in another machine, it shows up as RAW, and says it is formatted. Any suggestions appreciated.
modem7
10k Member
So that floppies/diskettes can be exchanged between different drives, at the factory, each floppy/diskette drive has the radial position of its heads aligned to an international standard.
The symptoms that you describe are typical of a drive that needs a radial head alignment.
Wrote yesterday, not sure if I'm still in noobie moderator prison. Not seeing my post here. Tried adjusting the heads, but couldn't get it working with anything but the one disk I made with the drive. Changed back to the old heads and same result. Won't read anything but the disk that was made with the drive. How can I do a radial head alignment, other than eyeballing it?
modem7
10k Member
For 5.25" drives, a special alignment floppy (expensive, and cannot be copied) is used together with an oscilloscope (connected to particular points on the drive's circuit board). A program is used too move the heads to a particular position on the alignment floppy. Then, the radial position of the head carriage is finely adjusted until the correct waveform is seen on the oscilloscope. The 5.25" drive maker's technical manual usually includes that information together with how to finely adjust the radial position (which screw, cam, ...)
There is also a 'track zero' adjustment.
3.5" drives will be similar, except that when I look at some 3.5" drive manuals on the Internet, I cannot see alignment instructions. Maybe the makers thought that, considering the (relatively) low cost of 3.5" drives, that people would be buying a new drive rather than paying for repair/realignment.
At the second post of the thread at [here], someone used an alternative method to align their 3.5" diskette drive.
Both heads need to be radially aligned. For the 5.25" drives that I have worked on, it was the complete head carriage that had drifted out of radial alignment, and so once I had the top head in the required alignment, I then found that the second was also in alignment (within the specification tolerances).
There is also a 'track zero' adjustment.
3.5" drives will be similar, except that when I look at some 3.5" drive manuals on the Internet, I cannot see alignment instructions. Maybe the makers thought that, considering the (relatively) low cost of 3.5" drives, that people would be buying a new drive rather than paying for repair/realignment.
At the second post of the thread at [here], someone used an alternative method to align their 3.5" diskette drive.
Both heads need to be radially aligned. For the 5.25" drives that I have worked on, it was the complete head carriage that had drifted out of radial alignment, and so once I had the top head in the required alignment, I then found that the second was also in alignment (within the specification tolerances).
As per Modem7's link above; I have used IMDisk to align a floppy drive with nothing more than a known good factory produced disk (I used a Windows 3.11 install disk). The use of a factory produced disk is critical; they are the most likely to be written correctly (and not by some dodgy half aligned disk drive).
It's tricky and takes a lot of patience. You need to make adjustments until it finds track 0, then skip through the tracks until it fails to find one, make another adjustment until it does, go back to track zero, and repeat until it works reliably. I spent maybe 30-40 minutes going back and forth however did get it to work 100% though. That particular drive is still going strong today.
I have also used alignment floppy disks with an oscilliscope. That is far easier and quicker; however I must admit the end result is pretty much the same.
It's tricky and takes a lot of patience. You need to make adjustments until it finds track 0, then skip through the tracks until it fails to find one, make another adjustment until it does, go back to track zero, and repeat until it works reliably. I spent maybe 30-40 minutes going back and forth however did get it to work 100% though. That particular drive is still going strong today.
I have also used alignment floppy disks with an oscilliscope. That is far easier and quicker; however I must admit the end result is pretty much the same.
dennis1967
New Member
- Joined
- Apr 14, 2020
- Messages
- 2
hello senior moderator,
I have a working Tandy 3000 except the original floppy drive is damaged So I got a like replacement off Ebay. but I think it's out of alignment. I would need a modified ribbon cable so that a standard floppy drive would work. The tandy floppy is powered by ribbon unlike the standard floppy
I have a working Tandy 3000 except the original floppy drive is damaged So I got a like replacement off Ebay. but I think it's out of alignment. I would need a modified ribbon cable so that a standard floppy drive would work. The tandy floppy is powered by ribbon unlike the standard floppy