Re: _please_ tell me the schematic for a scan doubler

[CUTblakeney@home.com (Jeff Blakeney)]

On Wed, 08 Mar 2000 21:18:27 -0800,
jonINTERNETrelayCHAT@napaVALLEYnet.CLARInet (Jon Bettencourt) wrote:

>Please send me the schematic for a scan doubler, or the number of the
>capacitor/oscillator in the IIgs to replace to change the RGB port's
>frequency to 30KHz and the value of the replacement capacitor.

You're asking for something that isn't very easy to provide.  A scan
doubler has to do some pretty fast signal processing and needs to be
made in such a way that it doesn't filter out any of the high
frequency signal.  There are probably a couple ways to do it but I
don't have a schematic for one and even if I did, I'm sure the parts
would be fairly expensive.

As to changing a capacitor value in a IIgs to convert it to 31 KHz, I
doubt it is that easy.  Again, I haven't looked into doing this nor
have I heard of anyone who has done this.

I know that there are scan doublers available for the Amiga and these
should work on a IIgs with a proper cable and I have also heard of
people modifying 31 KHz monitors to accept 15.75 KHz signals but I
don't have any details on these.

Sorry I couldn't be more help.

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