MOTM

Hey there...
I tracked down a short in my system to the MOTM 800... It's not the 
wire so it has to be in the module somewhere... I double checked and 
everything is in the right place. Any ideas?

Dow

Any solder bridges?  Check particularly carefully on the no-clean 
solder stuff - it acts like glue when molten...

Mike

--- In motm@y..., dowk@e... wrote:
> Hey there...
> I tracked down a short in my system to the MOTM 800... It's not the 
> wire so it has to be in the module somewhere... I double checked 
and 

> everything is in the right place. Any ideas?
> 
> Dow

Did this module ever work or has it had this problem since construction?

Check your ICs for correct orientation.  As simple as it sounds, that is an
easy mistake.  In fact, my only MOTM construction failure ever came from
making that mistake.

Larry H

--- In motm@y..., dowk@e... wrote:

> I tracked down a short in my system to the
>  MOTM 800... It's not the wire so it has to
> be in the module somewhere... I double checked
> and everything is in the right place. Any ideas?
>
> Dow

You can cut your potential culprits in half by determining whether 
the +15v or the -15v line is shorted. Plug it back in briefly, long 
enough to check the power supply voltages, and see which one doesn't 
measure correctly.

Are you sure the polarity on your electrolytic caps (the tall cans) 
is correct?

Moe

--- In motm@y..., dowk@e... wrote:

> I tracked down a short in my system to the
>  MOTM 800... It's not the wire so it has to
> be in the module somewhere... I double checked
> and everything is in the right place. Any ideas?
>
> Dow

In a message dated 7/30/2001 6:52:49 PM, jlarryh@... writes:

<< Did this module ever work or has it had this problem since construction?
 >>

If it didn't, I'd suggest looking at connections to the rails (+15V, -15V 
points) -- both were the PSU connects to the PCB (through the MTA .156 
connector), all the ICs, and any polarized components (especially diodes and 
electrolytic caps).

Since just having this module connected to the system affects the operation 
of other modules, it just seems like this is where the problem is. Since 
you've got the module out of your system, you might put an ohm meter across 
to see what the resistance is between each rail and ground, if that's real 
low then it probably is.

JB