Re: 50 / 60 Hz in Display control panel

["Ken Schunk" <kschunk@nycap.rr.com>]

Thank you very much. Worked like a charm.

Is there any on-line resource that lists the key combinations for things
like this? I realize it's probably in the manuals, but since those didn't
come with the computer... Guess my old Apple ][ knowledge isn't exactly
paying off yet :)

Ken Schunk

Mitchell Spector wrote in message <10AUG199803242128@vax2.concordia.ca>...
>In article "Ken Schunk" <kschunk@nycap.rr.com> writes...
>
>>I recently purchased an Apple IIgs, and I'm having one problem with it. I
>>can't get it to display composite video correctly on most of the TV's that
>>I have tried. Only an older B&W with a vertical hold control allows me to
>>get a stable picture.
>
>    A plain RCA cable running between the back of the IIgs and your
>TV (with 'Video IN' terminal) or VCR should work fine. It outputs a
>composite video signal through the composite port (just below the
>power plug) which is decent enough when it is emulating an older
>Apple IIe, but in native mode your going to want an analog RGB
>monitor for the GS's color and resolution. In either case, you
>will get a stable viewable picture, just not necessarily the
>nicest.
>
>>I noticed in the Display control panel that it indicates "50 Hertz".
>>I also noticed that my emulator software says 60 Hertz. Just what is
>>this 50/60 Hertz item, and would it have any impact on the composite
>>video output?
>
>    That is the problem. North American (and Japanese) TV sets
>operate at 60 Hz and the IIgs is sending a video signal at 50 Hz.
>The vertical scanning frequencies don't match, which is what is
>responsible for determining the refresh rate of your screen. TV's
>and composite monitors seem to operate on a fixed frequency, so
>sending them something they're not expecting is going to give an
>unstable image, to say the least.
>
>    To fix this, turn on your IIgs while holding down the 'Option'
>key (or if already on, press and hold down Option-Control-Reset,
>while continuing to hold down the Option key after releasing
>the others). When the menu appears, select option "2" by pressing
>the 2 key. This is set the refresh rate back to 60 Hz, as well
>as restore all the factory Control Panel settings. You may want
>put them back, which can be done by repeating the above steps
>and pressing "1"m or pressing and holding down Apple-Control-Esc
>and then selecting 'Control Panel'.
>
>Mitchell Spector
>spec@vax2.concordia.ca