Apple IIgs question..

From: Ian Primus <ian_primus_at_yahoo.com>
Date: Wed Jun 4 19:13:00 2003

Sounds like a weak PSU, I have had no trouble using ADT on a IIgs. How
much stuff do you have connected to it? I know I have found that after
two Unidisk 5.25's, two 3.5" drives, two Disk II's, a SCSI card, RAM
expansion, etc, etc, it the computer sometimes can't get the juice to
power drives, I/O, etc (especially those pesky Disk II's)... Try
measuring voltages at the power supply, it should have the pinouts
printed on it IIRC. If you want, I have a spare IIgs or two that you
can have for a few bucks plus shipping. I also have IIe's and floppy
drives as well, if you want.

Ian Primus
ian_primus_at_yahoo.com

On Wednesday, June 4, 2003, at 07:30 PM, David Holland wrote:

> Hi, all..
>
> ( Gee, I get to ask a legitimate classic comp question.. )
>
> Anyways, I've a A2GS sitting here, that I've been beating myself over
> the head with for about two days now.. (Yes, I'm stubborn)
>
> I've been trying to get ADT (serial) working between the GS, and my PC.
>
> I've gotten it to work just fine PC -> GS. (I even had my PC type a
> copy of Dos3.3/ADT/ADTgs in via the serial port at 300baud.)
>
> Anyways the stumper is in the GS -> PC direction. Nothing works. I've
> tried the modem port on the GS, as well as 2 different super serial
> cards.
>
> I finally got desperate enough to pull out a RS-232 break out box, and
> a
> scope. (Plus a couple of dweebie basic programs) What I find is the
> Apple serial communications looks like its running at about +/- 4v.
> (This is on the builtin modem port. I can't get a SSC to work
> either.)
> (The waveform also appears to have a fair amount of ring on the voltage
> swings, but that may be normal)
>
> I'm guessing that the +/-4volts isn't enough for my PC to recognize it.
>
> Question #1:
> Does anyone have any thoughts about my theory that the PSU is weak, or
> suggestions where else to look?
>
> Question #2:
> Presuming question #1 is reasonable, schematics for a GS PSU?
>
> Thanks,
>
> David
Received on Wed Jun 04 2003 - 19:13:00 BST