Dotcomformat

I have a MOTM based setup currently but would like to get some dotcom 
modules. My problem is that the dotcom power supply is way to 
expensive to justify when I already have power minus the 5v. I know 
there is the $12 power adaptor that arrick sells for converion but 
that's $12 a pop per module. One can get a powerone 5v PS for under 
$35 which is a much cheaper alternative and then get the dotcom power 
harness. My question mostly is about a grounding scheme for the 2 
PS's (MOTM and a seperate 5v) and also I don't see the pinouts of the 
4pin molex connector on the PS end of the dotcom power harness. Any 
ideas or solutions?

- Michael nil-x
- Pressure : Penetration

That one I did see also but it only powers 8 modules - for about the 
same $ I can power 22 give or take as long as it's possible to add 
that extra 5v PS with no grounding issues. I suppose the other 
solution would be to get a PowerOne HCBB-75W-A which is the same spec 
as the dotcom QPS1 supply but only $109 and build my own "harness" in 
the MOTM style.

Another question: Does anybody know offhand if the 6pin MOTM MTA is 
the same pinout as the DOTCOM on the new MOTM PS?

- Michael nil-x
- Pressure : Penetration

--- In dotcomformat@yahoogroups.com, Morbius <morbius001a@y...> wrote:
> Besides the standard dotcom power supply, there is the
> QPS2 Power Supply @ $85 (comes with cables).

Besides the standard dotcom power supply, there is the
QPS2 Power Supply @ $85 (comes with cables).


--- Michael <nil@pressurepenetration.com> wrote:

> 
> I have a MOTM based setup currently but would like
> to get some dotcom 
> modules. My problem is that the dotcom power supply
> is way to 
> expensive to justify when I already have power minus
> the 5v. I know 
> there is the $12 power adaptor that arrick sells for
> converion but 
> that's $12 a pop per module. One can get a powerone
> 5v PS for under 
> $35 which is a much cheaper alternative and then get
> the dotcom power 
> harness. My question mostly is about a grounding
> scheme for the 2 
> PS's (MOTM and a seperate 5v) and also I don't see
> the pinouts of the 
> 4pin molex connector on the PS end of the dotcom
> power harness. Any 
> ideas or solutions?
> 
> - Michael nil-x
> - Pressure : Penetration
> 
> 
> 
> 



		
__________________________________ 
Do you Yahoo!? 
Check out the new Yahoo! Front Page. 
www.yahoo.com

--- Michael <nil@pressurepenetration.com> wrote:
> .... as long as it's possible to add that extra 5v PS with no
> grounding issues.

There is no problem with adding the 5 volt supply to a +/-15 supply. 
You could make your own MOTM-like distribution PCB for the dot com
connectors if you did not want to use the dot com style harness.

> Another question: Does anybody know offhand if the 6pin MOTM MTA is
> the same pinout as the DOTCOM on the new MOTM PS?

It really does not matter since they are different sizes.  The MOTM
is MTA-156.  Dot com is MTA-100.  I don't have the pin out for the
dot com modules.  But the nice thing about the MTA100 is that you can
get a generic proto or stripboard PCB and mount the MTA headers to it
since the pin spacing is the same as the 0.1" spacing on protoboards.

The common point for the 2 grounds of the separate power suppies
should be right at the power supplies.  Be sure to make both the AC
earth ground and the DC side ground common to both supplies.  But,
keep the earth goound and DC ground separate.

Of course, the right answer is buy the 3 output triple supply since
you will eventually need more power supply to feed your addiction. 
I've got one that is 5000ma each +/-15 and I have outgrown it.

Larry H.



		
__________________________________ 
Do you Yahoo!? 
Check out the new Yahoo! Front Page. 
www.yahoo.com

Ahh very cool, that's what I figured for the PS ground connections 
but I really wanted to make sure (can never be too careful with 
voltage like that). Great to know the .100 MTA is .1" space, of 
course it makes sense to me now .100 = .1" :). That's great that I 
can make it on Perfboard too. I'm all about building as much as I can 
myself. Thanks so much for the info Larry.

- Michael nil-x
- Pressure : Penetration

--- In dotcomformat@yahoogroups.com, Larry Hendry <hendrysr@y...> 
wrote:
>(Lots of great info that you can read in the previous post...) :)