Drew wrote:
> On Nov 15, 2:05 am, "Michael J. Mahon"  wrote:
>> Drew wrote:
>>> On Nov 14, 7:45 am, Drew  wrote:
>>>> On 14 Nov, 06:12, Polymorph  wrote:
>>>>> On Nov 14, 11:38 am, Drew  wrote:
>>>>>> Hi,
>>>>>> After a bit of help again :-). I managed to pick
up a Philips CM8833-
>>>>>> II monitor today and was wondering if i needed to
do anything special
>>>>>> to get it to work? I did do a search of the forums
but didn't find
>>>>>> anything specific. Looking at the pinouts it would
seem I should be
>>>>>> able to use the cable I have for my Commodore
1084s, but when i use it
>>>>>> the picture just rolls i.e not in sync.
>>>>>> The cable I made for the 1084s is cabled as per
the faq and i get a
>>>>>> stable picture on my 1084s monitor...though red
isnt very good.
>>>>>> The only information i have found on the pinouts
for the philips
>>>>>> monitor are:-
>>>>>> 1,2 - Ground
>>>>>> 3 - Red
>>>>>> 4 - Greem
>>>>>> 5 - Blue
>>>>>> 7 - Status RGB
>>>>>> Any suggestions?
>>>>>> Many thanks
>>>>>> Andrew
>>>>> It may be like the 1084S monitor that I have hooked up
to my daughters
>>>>> IIgs in that it requires a small value resistor
between composite
>>>>> synch and ground.
>>>>> I refer you to the relevent thread
here:http://groups.google.com.au/group/comp.sys.apple2/browse_frm/thread/7...
>>>>> Have a read through that and see if it sounds
familiar. The solution
>>>>> presented within that thread did fix the problem for
me - the monitor
>>>>> in question has now been in use for nearly a year.
>>>>> If you get stuck or need pics of what I did, let me
know and I'll see
>>>>> what I can do.
>>>>> Cheers,
>>>>> Mike
>>>> Hi Thanks for the comments guys. I don't have a resistor
to hand, but
>>>> will try some of the comments about connecting the
composite sync to H
>>>> and V sync and possibly try sync on green.
>>>> Cheers
>>>> Andrew
>>> Hi,
>>> Well i got the monitor to sync putting the composite sync onto pin 2.
>>> Though was a bit disappointed with the picture as wasn't as clear/good
>>> as the 1084s-d2 monitor I have (well ignoreing the weak red
>>> colour ;-)). Had thought they were based on similar tubes....getting a
>>> nice collection of monitors though ;-)
>> It's almost certainly not the tube, but the adjustments or the
>> internal "matrix" resistors used to set the color mixes.
>>
>> The issue of clarity or resolution is another matter.  That can be
>> limited by the dot pitch of the tube, by the bandwidth of the video
>> amplifiers, or by focus adjustments.
>>
>> -michael
>>
>> ******** Note new website URL ********
>>
>> NadaNet and AppleCrate II for Apple II parallel computing!
>> Home page:  http://home.comcast.net/~mjmahon/
>>
>> "The wastebasket is our most important design
>> tool--and it's seriously underused."
> 
> Thanks for the info. The monitor is a 14 inch screen where the 1084s-
> d2 is a 13 inch so the dot pitch could make it look slightly worse
> picture.

Actually, making the physical screen bigger at the same dot pitch
will *improve* the number of physical phosphor dots per line.

But making a low-resolution picture bigger just makes it look worse,
regardless of the technology of the display.

If you want to look at Apple II-generated graphics on a large-screen
monitor, you will be dissatisfied unless you back up until the large
display subtends about the same visual angle as a 12"-13" display
right behind the computer.

> Interestingly the CM8833-ii monitor will sync on Pin2
> (Ground), and Pins 8 and 9 (V and H Sync) and also pin 7 using the
> composite sync from the GS.

So, evidently, pin 2 is not ground!  Many monitors that can handle
composite sync will actually use it in place of V and H--I'm glad that
your's is one of them.

You may find that the different inputs will have different stabilities
depending on the level of the composite sync signal that is presented.
A simple resistive attenuator (variable is easiest to play with) would
allow you to explore these possibilities if it's still not stable.

The other major issue is sync polarity.  Some monitors want positive
sync pulses, while the more common choice is negative.  For these cases,
an inverter is required (one chip or even one transistor).

-michael

******** Note new website URL ********

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