Re: multi-game proto board

On Fri, 2 May 1997, Zonn wrote:
> There is just one thing though. The difference between the Sega monitors
> and WG is more than just level shifting. The Sega monitor is capable of a
> faster vector sweep rate.

Right.

> The WG will not be able to keep up with Sega
> vector generator.

Right again. But it *almost* can, and the results of using just the level
converter alone are quite acceptable (to me, at least)-- just the
occasional stray vector.

> I haven't tried this but my guess is that in order to see
> a non-distorted picture, your going to end up with a shrunkin image centered
> on the WG.

I *have* tried this, and can confirm that Zonn's guess is correct. But
the level at which the slew-rate problem disappears makes the screen
annoyingly small--about half-size.

> The fix for a WG would be a little involved, but not a lot. I would suggest
> parallelled transistors to handle the higher wattages...

I've been meaning to try this... it would be great if the upgrade would
work using a bunch of 3716's and 3792's.

> But mostly it would be changing values here and there to handle
> the higher +/- 50 volts.

I'm sure there's some sort of arrangement that would allow you to jack up
the current without changing the working voltage (somehow I keep thinking
of a Darlington arrangement but my analog knowlege is VERY rusty; gonna
have to look it up).

                                                             --Dave--
Received on Sun May 4 18:53:57 1997