24 Jan
2007
24 Jan
'07
2:58 a.m.
-----Original Message-----
From: cctalk-bounces at classiccmp.org
[mailto:cctalk-bounces at classiccmp.org]On Behalf Of M H Stein
Sent: Tuesday, January 23, 2007 5:52 PM
To: 'cctalk at classiccmp.org'
Subject: Tandon TM848-2 Floppy drive power
------------------Original Message:
Date: Tue, 23 Jan 2007 11:23:32 -0500
From: "Kelly Leavitt" <kelly at catcorner.org>
Subject: Tandon TM848-2 Floppy drive power
To: <cctalk at classiccmp.org>
Message-ID:
<07028839E9A3744F87BEF27FF2CFF8E30B1494 at MEOW.catcorner.org>
Content-Type: text/plain; charset="UTF-8"
The drive in my Tandy Model 6000 has +5, +12 and +24
connected to it (pins 5, 4, and 1). The schematic in the
service manual I have shows 4 as NC and a 7812 providing the
12v from the 24v line. The specs for the drive in the service
manual do not mention +12 on pin 4 at all. The scematic at
bitsavers isn't a lot of help.
I don't have the drive here in front of me. Does anyone have
one where they can verify the connections from the AMP power
connector to see if pin 4 actually goes anywhere on theirs?
-----------------Reply:
The drive in front of me corresponds to the service manual, i.e.:
AMP PCB P7
1 1 - +24V
2 2 - GND
3 3 - GND
6 4 - GND
5 5 - +5V
4 NC
OK, I'm home looking at the drive. The wiring harness from the power
supply does connect +5, +12, and +24 to the plug that goes into the drive. However the
TM848-2 drives have pin 4 vacant on the connector on the drive. That is, there is no pin
there. Sounds dangerous, but that is typical of Tandy's shortcuts.
Hope that's clearer than mud & helps.
It is, it does.
mike
Thanks,
Kelly
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.410 / Virus Database: 268.17.8/649 - Release Date: 1/23/2007