Marty Tamura PSU schematics

Started by Unstablewarpfield, May 24, 2020, 04:05:13 AM

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Unstablewarpfield

Hello! My first post on here, so here it goes...

Since about a month or two I'm the proud owner of a broken Marty. I bought it to work on it as a project during these lockdown days.

First thing I did was strip the complete powerboard and tried to make the schematics for it since they don't seem to exist on the web. I was wondering if anybody could verify the schematics I came up with. At some point you are staring at the circuit board for so long figuring out all the connections that a small mistake is easilly made.

These are the schematics I came up with:


Furthermore... I scanned the powerboard (top and bottom) to get the exact dimensions. Those look something like this:
Solder side


Component side


And as last... I am using the dimensions to create a replacement PSU that will work on 230V as well as 110V. I used three power modules to create the 5V, 9V and -9V needed. It will require desoldering of the original AC input, bracket, CN1 and power switch, so that a clean installation is achieved.

This is REV1 of the board:
Top


Bottom


As always... suggestions and corrections are always welcome :-)

virtjunk


Cyothevile

What's your BOM for one card?

I think there could be a cheaper way to make one of these replacement cards by using 7909 to drop -12V from ITX pico PSU to -9V, 7809 to drop 12V to 9V, right angle 20 pin molex and right angle barrel jack for a power brick.  Pull PS_ON line to ground with the switch to power on and off. Don't forget decoupling capacitors for both regulators