[Coco] Program for test pattern for crt alignment/convergence?

[Don Barber]

Thanks Mike. I was thinking I might have to solder in a NOR gate to get 
a negative composite sync for this monitor, but fortunately the hsync 
and vsync lines direct to pins 8 and 9 worked great. The 1084S-D1 seems 
to take either. I understand this isn't true for all of the 1084 series.

Don

On 8/8/22 15:38, Mike Delyea via Coco wrote:
> You may have an issue with the sync when hooking up to a coco III.  I did
> this many years ago and I remember I had to create a little circuit with a
> 74ls flip flop to invert the sync.  I posted the instructions along with a
> crude diagram on one of the coco sites that is now defunct.  Maybe its
> archived somewhere.
>
> On Mon, Aug 8, 2022 at 2:15 PM Eric Canales via Coco <coco at maltedmedia.com>
> wrote:
>
>> I wouldn't use a coco calibration tool. The issue with the CoCo is it's not
>> particularly designed to give you an accurate picture and resolution that
>> fills the entire tube.
>>
>> What I'd suggest is instead hook up a nice DVD player to the monitor, and
>> then use a standard calibration DVD to generate the patterns. Spears &
>> Munsil is quite good:
>>
>>
>> https://www.amazon.com/Spears-Munsil-High-Definition-Benchmark-Blu-ray/dp/B0
>> 0UGQ8GEU/ref=tmm_dvd_swatch_0?_encoding=UTF8&qid=1659982222&sr=8-1
>> <https://www.amazon.com/Spears-Munsil-High-Definition-Benchmark-Blu-ray/dp/B00UGQ8GEU/ref=tmm_dvd_swatch_0?_encoding=UTF8&qid=1659982222&sr=8-1>
>>
>> Make sure to get the DVD version if you're using composite, or get the
>> bluray if your bluray player has a good composite out. If you try to
>> downconvert and HD signal you'll also be calibrating for your down
>> converter, which tbh probably wouldn't be a big deal for use with the CoCo.
>>
>> One day I want to make a calibration tool for the CoCo but it's going to
>> require quite a bit of testing, trying out various models of monitors and
>> CoCos, and it's just much simpler to use a DVD player which is made to give
>> you the most accurate picture it can.
>>
>> -----Original Message-----
>> From: Coco <coco-bounces at maltedmedia.com> On Behalf Of Don Barber via Coco
>> Sent: Monday, August 8, 2022 11:28 AM
>> To: coco at maltedmedia.com
>> Cc: Don Barber <don at dgb3.net>
>> Subject: [Coco] Program for test pattern for crt alignment/convergence?
>>
>> Hi folks, acknowledge I'm sending a lot to the list recently but I got a
>> lot
>> of projects going on.
>>
>> I'm replacing the tube of a Commodore 1084S-D1 when the old crt tube 'let
>> the vacuum out.'
>> I've got it aligned pretty close by eye but to get it exact I'd like a
>> proper test pattern, like white-on-black grid lines to get it just right.
>> I've already soldered up the cable to get this monitor working on the coco
>> so was hoping to be able to generate such a test pattern from the coco.
>>
>> As such, anyone know of a coco program to generate decent test patterns,
>> specifically a grid / cross-hatch pattern?
>>
>> I found Coco Color Bars (
>>
>> https://colorcomputerarchive.com/repo/Disks/Demos/Coco%20Color%20Bars%202020
>> %20(Jason%20Reighard
>> <https://colorcomputerarchive.com/repo/Disks/Demos/Coco%20Color%20Bars%202020%20(Jason%20Reighard>
>> ).zip
>> ) which is awesome - but still looking more for the grid test pattern.
>> Figure I could probably whip something out in basic without much effort but
>> thought maybe someone would know of an existing one?
>>
>> Alternatively I could probably get a CGA cable together to hook up this
>> monitor to an early PC if someone has an early dos program to generate a
>> test pattern.
>>
>> Don
>>
>>
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