T.R | Title | User | Personal Name | Date | Lines |
---|
5230.1 | | ULTRA::KINDEL | Bill Kindel @ LTN1 | Mon Nov 25 1991 12:47 | 34 |
| Re .0:
> I can sadly report that my amiga has thrown its hand in four days
> before its warranty has expired and will not be in my possession for
> the next 3-4 weeks.
>
> Whats worrying me is that I may have caused the fault to develop,
> the problem is that sometimes the workbench prompt doesnt appear and
> when it does its about a 50/50 chance of it loading anything from its
> one and only drive.
>
> All this happened about a week after installing the following on
> my machine;
> 1. A vr241 monitor.
> 2. A 501 ram expansion with clock.
> 3. A small one watt output amplifier from Tandys.
> 4. A pair of speakers.
Unless the input is shorted, neither #1 or #3 is likely to have ANY
affect upon the ability of your A500 to read DF0: The speakers in #4
connect to the amplifier in #3, so they don't count, either.
That leaves #2, which COULD do bad things to the A500 if you weren't
careful. The worst case would be if you did physical damage to the
A500 motherboard by jamming the A501 in incorrectly. (That's pretty
dire -- take out the A501 and see if the problem goes away. If so,
then either you have a defective A501 or it didn't make proper contact
when you installed it the first time.)
> In the mean time I will just have to twiddle with my thumbs, if anyone
> thinks I may have caused the problem or knows what the problem is
> please reply.
Done.
|
5230.2 | Watch out for the video connector | GVA02::SLOAN | we have met the enemy and he is us | Tue Nov 26 1991 03:02 | 12 |
| did you make up your own cable for the VR241? I know there is power on
some of the pins of the D type output, because I had similar problems
when I fitted a 241 to my A500.
However, it seemed to be the +12v which blew, as the only thing which
stopped working was the serial line to the printer. I changed the
regulator in the PSU to get the +12 back, but unfortunately the serial
line still doesn't work! Everything else is OK.
Does anyone know if there is an internal fuse I may have blown?
Steven
|
5230.3 | Thanks for the advice | JOCKEY::LUDLAMA | | Tue Nov 26 1991 11:21 | 8 |
| I did make my own cable for the VR241 but I 100% sure that there
are no power connections made.
Regards Arron.
P.S.
The note in this conference on making your own lead is pretty good.
I found that not only did I have to adjust the v.hold I also had to
adjust the internal colour and brightness controls.Finally, is
there anything you can do about the overflow ?
|
5230.4 | Think of it as a $20 to $40 fuse | TLE::RMEYERS | Randy Meyers | Tue Nov 26 1991 11:45 | 6 |
| Re: .2
>Does anyone know if there is an internal fuse I may have blown?
Unfortunately, the "internal fuse" is usually the CIA chip that controls
the serial or parallel port. :-(
|
5230.5 | "always use 1 amp fuses in all data lines..." | TFH::KIRK | a simple song | Mon Dec 02 1991 10:15 | 24 |
| re: Note 5230.2 by Steven "we have met the enemy and he is us"
There are internal fuses (not shown in the schematics), at least on my 2000.
[ power supply ]-------[ rectifier ]-------[ fuse ]-------> power to ports...
I believe the rectifier is to protect the Amiga from applying external power
through the ports. The fuse is a 4 amp "pico fuse", it looks a lot like a 1/2
watt resistor, except the markings are different. On the 2000 mother board,
they are around the back, near the port connectors.
You might try measuring the voltage at a variety of points along the way,
right at the power supply connector, on both sides of the rectifier, at the
port...and see if and where the outage is.
The symptom I was having was that my modem worked on my serial port, but my
MIDI box didn't. The modem was self-powered, the MIDI box got + and - 12
volts directly from the serial connector...
Hope this helps,
Cheers,
Jim
|