Re: IIgs to arcade monitor experiment

[MdntTrain <js@cimmeri.com>]

On Apr 22, 4:59 pm, Alex Freed <al...@mirrow.com> wrote:
> Yes, most likely about 2 Vpp at no load. Will look very washed-out,
> but nothing will burn.

* Yes, that's what I'm seeing on the 'scope, and on the screen
connected direct in.


> The ideal solution is using special hi frequency op-amps built pretty
> much for this purpose. Make it 8 Vpp at no load, add a series resistor
> of 68 ohm before the cable and a terminating resistor of 75 ohm at the
> monitor side. One per R G B.

*So you're suggesting to use an op-amp with about 8x amplification,
and on each of its outputs have a 68ohm series resistor... and to ADD
a 75ohm parallel (terminator) at monitor side _in addition_ to the
monitor's 5k terminator?   (On the monitor side, the signal comes in,
sees a 5k terminator, then a series 4.7k before entering as the base
of a simple 3 stage transistor amplifier controlling the CRT cathodes
-- very direct CRT control).

Alex, what about on the opamp input side?  Won't I need to terminate
those at 75ohms?

With gratitude,
 JS