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386 machine FDD problem
- Thread starter Dusannn
- Start date
patscc
Veteran Member
If you do live in Oagadougou, you might be able to find them at Reflex or Entrelec.
patscc
patscc
DOS lives on!!
Veteran Member
From the picture of the motherboard, it does support an external battery. The connector for it is under the keyboard port. I bought this battery to replace the one in a similar computer.
modem7
10k Member
And sometimes a jumper needs to be changed to switch between 'internal' and 'external' batteries.
modem7
10k Member
For this application, replacing a Ni-CD with Ni-MH should work (reference: 'Replacing NiCds with NiMH cells:' section of http://www.ka7oei.com/nicds.html).
Chuck(G)
25k Member
So... I can use internal Ni-Mh istead of Ni-Cd?
In my country i can buy new Ni-Mh 80mAh 3.6v batteries.
Yes, they should be fine--the current draw on the typical clock battery is probably less than the self-discharge current (microamperes, usually). However, if this were my board, I'd just buy a 4xAA battery holder and stick some alkaline cells in it and use the external battery connector. 4 AA alkaline cells will run for years before needing replacement--and they're readily available and inexpensive.
Stone
10k Member
6v to replace 3.6v? Wouldn't a 2 or 3 (i.e., 3v or 4.5v) pack suffice?
Chuck(G)
25k Member
It doesn't really matter--if you look at the circuitry used for an external (non-rechargeable) battery, at least 2 diode drops (~~1.4V) are involved. 6V gives you a bit more headroom on battery life, since most of these RTC chips are good down to about 2.2V. Max rated power supply voltage is about 7V.
Stone
10k Member
Good to know that. Thanks for the info.
patscc
Veteran Member
If it truly is a scratch on the floppy, and not just a white smudge, then the floppy is toast. You'd have to open up the drive and look at the head assembly to see if it's a head torn loose, or what. Unless it's a really rare and special drive, probably not worth fixing.
patscc
patscc
Stone
10k Member
It could be that the drive needs its heads cleaned, especially if this ‘scratch’ is circular near the circumference of the disk. This is ususlly caused by bad disks, not the drive itself. When old disks deteriorate the oxide coating tends to collect on the heads and this can cause a ring scratch on the disk. Cleaning the drive with a cleaning diskette will usually solve this problem.
DOS lives on!!
Veteran Member
The liquid that I use on my cleaning disks is isopropyl alcohol 91% or higher.
Stone
10k Member
I think you can use methanol but be sure you don't drink any of it.
patscc
Veteran Member
That's great it worked, but be careful with the QTips, as the fibers can sometimes snag and get stuck.
patscc
patscc
Cleaning diskettes sacked anyway. Nothing like opening the drive and cleaning it with some cotton and cleaning fluid. Alcohol can be used, although I also have used acetone without problems (assuming you keep it away from the plastic parts). The best cleaning fluid IMO however, is the one they use for cleaning the glasses (for the house doors, windows etc).