Tech: Rottendog DPS004 HV

stangbat

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Jan 16, 2011, 4:19:27 PM1/16/11

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I have a Rottendog DPS004 and I get the following voltages on the HV
outputs and at the DMD connector:

Under load, DMD connected:
-100v = -136v
-110v = -150v
+68v = 65v

Seems too high. The DMD seems too bright and is noisy.

DMD disconnected, no load:
-100v = -85v
-110v = -156v
+68v = 68.2v

DMD is a Cherry. I'm guessing it is the newer design, it has basically
no components on the back of the PCB.

The DMD works, but unfortunately I didn't check this until today.
Hopefully I haven't damaged it.

--
stangbat
This USENET post sent from http://rgparchive.com

stangbat

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Jan 17, 2011, 11:52:00 AM1/17/11

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I haven't heard back from Jim. I've done some searching and reading and
I'm beginning to wonder what is going on. The schematics on Rottendog's
site and that were included are nothing like the PS I have when it comes
to the HV section. I was going to check the adjustment resistors for
each LM337 but they are different values than what is in the schematics
and there is an additional resistor added in both negative HV sections.
Hard to double check stuff when the schematics aren't right.

I think this PS has fried my DMD. It works, but it doesn't work right
on a PS that puts out the correct negative voltages. I now realize what
was going on when I posted this:
http://tinyurl.com/4cgoma8

The reason the SW DMD didn't work in JP is because it has been
over-volted in the SW. When it was given the correct voltages in JP, it
was dim. I'm just glad I didn't put the JP DMD into SW when I was
testing stuff.

stangbat

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Jan 17, 2011, 1:35:01 PM1/17/11

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Spoke to Jim, sending it back.

mr tobias

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Jan 17, 2011, 1:41:44 PM1/17/11

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I had a similar problem with the same model of board. The high
voltages were way out of spec, only in my case the result was the DMD
didn't light at all. I'd had the board for quite a while as a spare
before I found out it wasn't working right. Had to put it down to
experience.

stangbat

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Jan 17, 2011, 2:08:26 PM1/17/11

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I found another post here on RGP where someone was reporting basically
the same voltages as me. Must be a bad batch of LM337s out there.

GPE

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Jan 17, 2011, 2:35:06 PM1/17/11

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There's nothing wrong with the LM337's if they were used according to
manufacturer's specs.
The problem is the board is exceeding the manufacturer's absolute
maximum specs by more than 3x.

stangbat

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Jan 17, 2011, 2:54:06 PM1/17/11

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GPE;1607229 Wrote:

> On Jan 17, 1:08*pm, stangbat <stang... (AT) gmail (DOT) com> wrote:
> > I found another post here on RGP where someone was reporting
> basically

> > the same voltages as me. *Must be a bad batch of LM337s out there.

> >
> > --
> > stangbat
> > This USENET post sent fromhttp://rgparchive.com
>
> There's nothing wrong with the LM337's if they were used according to
> manufacturer's specs.
> The problem is the board is exceeding the manufacturer's absolute
> maximum specs by more than 3x.

So I guess the choices are find a replacement DE PS or go with a
PinLED? Or does someone else made a suitable replacement DE PS?

This game did not come with a PS so I don't have one available that I
can rebuild. If I had one to rebuild, I would.

No matter what, I'm going to need a new DMD.