> -----Original Message-----
> From: Tony Duell <ard.p850...@gmail.com>
> Sent: 24 May 2020 10:28
> To: r...@jarratt.me.uk
> Cc: General Discussion: On-Topic and Off-Topic Posts <cctalk@classiccmp.org>;
> Paul Koning <paulkon...@comcast.net>
> Subject: Re: Alternative Monitor for VAXmate
>
> On Sun, May 24, 2020 at 9:23 AM Rob Jarratt <robert.jarr...@ntlworld.com>
> wrote:
>
> >
> > Tony, are you aware of any device I could buy or circuit I could build to
> > get a
> decent image out of it? It doesn't have to be perfect, but at least usable.
>
> Unfortunately not. That 26kHz horizontal frequency is the problem...
>
> It's not close to any of the PC standards (MDA, CGA, EGA, VGA). Nor television
> (I even thought of the French System E 819 line, but that's around 20kHz). And
> those are the common standards.
>
> I think you options are either to try to modify VGA monitor to scan a little
> slower, to design some kind of standards converter (which is a lot of work!)
> or
> to make a new flyback transformer. The last would be what I would look into,
> if
> only because it keeps the machine original.
> You would probably have to vacuum-impregnate the windings to prevent
> flashover, but the model internal combustion engine crowd make their own
> ignition coils and manage to do things like that.
Everything I have ever heard would suggest that making my own flyback is the
hardest option and well nigh impossible without expensive industrial equipment.
If there was a way I would certainly look into it. I have no idea where to
begin, but if anyone on this list has any pointers?
>
> -tony