Re: Monocrome monitor on a IIe or IIc

[pausch@saaf.se (Paul Schlyter)]

In article <3D81B78C.559559FE@t-online.de>,
Carlo Porst  <c.porst@t-online.de> wrote:
 
>Hello Paul,
>
> I've found this information about the Apple monochrome Monitor
> (A2M6016) in the Apple Til:
>
> I. Technical Specifications
> A. Picture Tube:
> -- 12-inch diagonal
> -- Phosphor EIA Type: P4 (White)
> -- High contrast
> -- When used with Apple IIGS applications that generate
> color, it displays up to 16 shades of gray.
> -- Anti-glare
> -- Text display: 80 columns by 24 lines
> B. Input Signal:
> -- Composite synchronous negative 1.0 +/- 0.5 volts peak to peak,
> internally terminated with 75 ohm resistor.
> C. Scanning Frequencies:
> System: NTSC/60 NTSC/50-PAL/50
 
...and why on Earth would a MONOCHROME monitor care whether the
COLOR is encoded as NTSC or PAL ???????
 
> 1. Horizontal: 15.734 kHz 15.659 kHz
 
Yep, the horizontal frequency is nearly the same for the 60/525 and
50/625 systems, so there's no need to adjust the horizontal sunc when
switching between 50 and 60 ...
 
> 2. Vertical: 60 Hz 50Hz
 
...but the vertical sync may need some readjustment!
 
Many years ago, I had a monochrome monitor for my Apple II+: a
motherboard jumper let you adjust the video output to eother 50 or 60
semiframes/second.  Initially it was on 50 (since it was sold in
Europe), but later I changed it to 60: when I got my first PC, with a
CGA graphics card (which had a composite video output) I shared the
monitor between the Apple II and the PC.  When switching the monitor
between the computers, I always had to readjust the horizontal sync,
until I realized I could change that Apple II motherboard jumper to
make my Apple II output 60 semiframes/sec too!!!
 
> D. Video Bandwidth:
> -- Less than 3 DB down at 12 MHz.
> E. Resolution:
> 1. Apple IIGS: 640 horizontal by 200 vertical pixels
> 2. Apple IIc: 560 horizontal by 192 vertical pixels
>
> III. System Configuration
> -- Apple IIGS
> -- Apple IIc
>
>Does that make a difference regarding your statement?
>I just wonder why the Apple IIe isn't mentioned.
 
No -- it makes no difference.  Since monochrome monitors don't
use the color signals, it doesn't matter at all whether it's
encoded in NTSC or PAL.  You may have to readjust the horizontal
sync though when switching between 50 and 60 semiframes/sec.
 
>Thanks
>Carlo
>
>Paul Schlyter wrote:
>
>> In article <3D80DE68.773656AC@t-online.de>,
>> Carlo Porst  <c.porst@t-online.de> wrote:
>>
>>> Is it possible to use an Apple monochrome monitor (m-nr.  A2M6016)
>>> directly with an IIe or IIc?
>>> Do I need a pal card for the IIe or a pal modulator for the IIc to use
>>> this monitor?
>>
>> Since the monitor is monochrome, the encoding of the color
>> information shouldn't matter at all, should it?  Therefore, whether
>> you use a PAL, a SECAM or an NTSC card (the latter is actually built
>> into the APple II motherboard) is completely irrelevant.
 
-- 
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