Re: Spinner problem w/Major Havoc & Tempest adapter

Grab some cold spray, and nail the suspect ic's! the one that gets the
spinner working, is it custom or off-the-shelf? If custom mount a
cooling fan on it, use one of those 486 ones with some liberal coating
of heatsink compound...this should get you through until a replacement
IC is designed/found

John :-#)#

Doug Jefferys wrote:
>
> On Sat, 6 Feb 1999, fishd wrote:
> >
> > I'm in the process of testing a couple of Major Havoc boards
> > with the Tempest/MH adapter but having problems getting the
> > spinner to respond.
>
> ...and while his fix was simple, that brings to mind something
> I saw a long time ago and never managed to fix.
>
> Running a Major Havoc board (no conversion kit) in a Tempest or
> Gravitar harness. Game powers up, plays fine for a few moments,
> but over time (30-40 seconds), the spinner becomes gradually
> less responsive and eventually completely unresponsive. Power-cycling
> the machine fixes the problem, but only for a few more seconds.
>
> It "feels" like an analog problem, say, a capacitor charging or
> discharging - the longer the machine is off, the longer it works
> before it fails again. Power off for a minute, get 30-40 seconds
> of spinner time. Power off for 5 seconds, get 10 seconds of spinner
> time.
>
> Obvious cause: Bad board.
> Unobvious fix: Sending the board to someone with a known working MH
> setup results in the board and spinner behaving fine.
>
> Obvious cause: Bad spinner.
> Unobvious fix: ...so why can I play Tempest normally?
>
> Obvious cause: Bad wiring.
> Unobvious fix: Problem reproduced on two separate wiring harnesses.
>
> Anyone else seen this kind of behavior? If so, what was the fix?
> (Things to do: Stick scope on CLK and DIR lines when I get things
> set up to test this again someday...)
>
> Later,
> Doug.
>
> --
> dougj |
> @ |
> hwcn.org |

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