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· Hardware
#Power Supply Rating
7 messages in this thread
Khalid, when the red light comes on, does the drive actually spin? The +15
is the one that runs the motor, and it could be that the 5 volts is
lighting the light, but that the 12 volts is not even being passed through.
This could also be the cause of the light glowing dimly, as some parts of
the circuitry could be left in a funny state due to the lack of 12 volts.
Since you say that it didn't work the first time you tried it, and that
you got around it by reversing the order of the two drives, then this will
be the problem. The seconddrive in the string, (and probably the last one
too) do not have the 12 volts passed through to the next drive.
You really have two choices in order to make use of all 4 drives. One is
to buy a small 12 volt power supply and wire it in to the last drive. The
other is to wire the 12 volts right on through on the second drive itself.
Please don't attempt this if you don't feel comfortable around a circuit
with a soldering iron, and without a thorough double check of the pinouts
vs. voltage readings with a meter.
Hi, Larry. I just tried putting the drives in all the nine possible
combinations. Still exactly the same happens to the last drive. All the
drives are new, and do pass on the both power lines. What happens exactly
is when I insert a disk into drive df3: the light comes on, sometimes
strong and sometimes weak, the drive starts spinning, but slowly, I think.
It tried to access the disk three times unsuccessfully and then DOS reports
a DF3:BAD. The sound of the drive is somewhat muffled, but that might be
because it is turning slowly. Any ideas?
I haven't looked at one, so this is just a guess, but it is
possible that to avoid problems, they installed some form of current
limiting in the power lines, thus not allowing enough power to "drive" the
3rd external drive. It would seem you'll probably have to add a 12v supply
yourself and probably a 5v supply also…make sure they are regulated as
overvoltage especially on the 5v line can cause you all kinds of
grief…such as a dead drive and/or Amiga. Hopefully someone from C-A will
jump in this thread with a more definitive answer.
Thanks, Don. That might be it. I will wait for a week or so before I go
ahead with the idea of supplying power direct to the last drive. Another
strange thing I found out about the power lines in the Amiga is that, as
you know, 1.2 adjusts automatically to PAL or NTSC Amigas, but when I
connect a 5.25" drive that is powered by 110v to my PAL Amiga, 1.2 thinks
that it is an NTSC one and limits the Workbench screen to 640×400. This
happens about one boot in five. What the hell for? Shouldn't it just test
the screen size directly? Or is my reasoning wrong?
Thanks, Don. That might be it. I will wait for a week or so before I go
ahead with the idea of supplying power direct to the last drive. Another
strange thing I found out about the power lines in the Amiga is that, as
you know, 1.2 adjusts automatically to PAL or NTSC Amigas, but when I
connect a 5.25" drive that is powered by 110v to my PAL Amiga, 1.2 thinks
that it is an NTSC one and limits the Workbench screen to 640×400. This
happens about one boot in five. What the hell for? Shouldn't it just test
the screen size directly? Or is my reasoning wrong?
I haven't looked at one, so this is just a guess, but it is
possible that to avoid problems, they installed some form of current
limiting in the power lines, thus not allowing enough power to "drive" the
3rd external drive. It would seem you'll probably have to add a 12v supply
yourself and probably a 5v supply also…make sure they are regulated as
overvoltage especially on the 5v line can cause you all kinds of
grief…such as a dead drive and/or Amiga. Hopefully someone from C-A will
jump in this thread with a more definitive answer.
Hi, Larry. I just tried putting the drives in all the nine possible
combinations. Still exactly the same happens to the last drive. All the
drives are new, and do pass on the both power lines. What happens exactly
is when I insert a disk into drive df3: the light comes on, sometimes
strong and sometimes weak, the drive starts spinning, but slowly, I think.
It tried to access the disk three times unsuccessfully and then DOS reports
a DF3:BAD. The sound of the drive is somewhat muffled, but that might be
because it is turning slowly. Any ideas?