[Coco] video composite on korean coco 26-3134A
didier derny
didier at aida.org
Sat Oct 4 01:59:30 EDT 2014
I tried, I was not expecting a correct image, but at least something like a
synchro
But nothing, just snow...
The tv see a "VCR" but no signal
Any idea if the modulator or the coco uses the 60hz ?
The power supply is 110v but 50Hz
That's why I have a serious doubt about this machine...
--
didier
-----Message d'origine-----
De : Coco [mailto:coco-bounces at maltedmedia.com] De la part de Zippster
Envoyé : samedi 4 octobre 2014 00:17
À : CoCoList for Color Computer Enthusiasts
Objet : Re: [Coco] video composite on korean coco 26-3134A
You could rig up a quick and dirty piece of coax cable from the RF port to
the antenna in jack on a tv and tune it to channel 3 or 4 (whatever the
switch is on). The picture may not even be that bad.
Or the relay.
-Ed
On Oct 3, 2014, at 4:30 PM, Chris <coronet1969 at gmail.com> wrote:
> type CLOAD and listen for the relay.
>
> On Fri, Oct 3, 2014 at 3:29 PM, Zippster <zippster278 at gmail.com> wrote:
>
>> Check for a clock signal and address/data line activity at the cpu.
>>
>> -Ed
>>
>>
>> On Oct 3, 2014, at 2:16 PM, didier derny <didier at aida.org> wrote:
>>
>>> I'll probably order a pcb
>>>
>>> My main problem, is that I have absolutely no idea if the coco 2 is
>> working
>>> at all
>>> I tested inside the modulator but I've not seen any signal looking
>>> like a video signal (no synchro seen)
>>>
>>> Is there any other way to know if it is dead or alive ?
>>>
>>> --
>>> didier
>>>
>>>
>>> -----Message d'origine-----
>>> De : Coco [mailto:coco-bounces at maltedmedia.com] De la part de
>>> Zippster Envoyé : vendredi 3 octobre 2014 19:21 À : CoCoList for
>>> Color Computer Enthusiasts Objet : Re: [Coco] video composite on
>>> korean coco 26-3134A
>>>
>>> Mike,
>>>
>>> I made this board to replace the RF modulator box that was in my
>>> Korean CoCo2.
>>> I removed the modulator, and soldered pin headers in where the
>>> inputs to
>> the
>>> modulator are. Y, øA, øB, CHB, CLK, Sound, and +5v are all in these
>>> headers.
>>> The area underneath the modulator is pretty much all ground plane,
>> allowing
>>> me to drill mounting holes for the board, and use standoffs to attach
it.
>>>
>>> Corresponding female headers on the board then just plug into the
>>> motherboard (except for
>>> 1 ground wire that needs to be attached). Then I made a cutout in
>>> the
>> back
>>> of the CoCo case, basically expanding where the RF connector was.
>>> It
>> makes
>>> for a pretty neat installation.
>>> (I’ll put some more pics up later).
>>>
>>> I’m not sure if all Korean CoCo2 main boards have the same layout in
>>> the modulator area, but I think we may have the same model, so it
>>> should
>> fit.
>>>
>>> I know other CC2’s have differing layouts for the modulator area,
>>> but
>> it’s
>>> easy enough to lay out a board to fit those (with measurements).
>>>
>>> I had also thought of the idea of a board plugging into the MC6847
>> socket,
>>> and moving it to onto the board, which is a good one. I’m planing
>>> on
>> this
>>> approach for a Component Video board I’m working on. It would be
>>> pretty easy to socket non-socketed 6847’s if you’re willing to
>>> sacrifice the
>> chip
>>> (utsource has them, I think I paid $5ea for five).
>>>
>>> - Ed
>>>
>>>
>>>
>>> On Oct 3, 2014, at 11:17 AM, mike at borncoco.com wrote:
>>>
>>>> Ed, I ordered some of your boards from OSHpark. Nice layout! I'll
>>>> have
>> to
>>> open up a Korean CoCo 2 this weekend to see how you made the
>>> connections
>> to
>>> the motherboard. Any info on what you must remove? If you already
>> discussed
>>> this here, just say so and I'll look in the archives later. As you
>>> said,
>> it
>>> would not be difficult to use clip leads to make the connections for
>>> any CoCo2. I am still interested in creating a version that can be
>>> plugged
>> into
>>> the 6847 socket. I know the other puzzle is that some models of the
>>> CoCo
>> 2
>>> have the RF modulator box mounted in different ways - some at 90
>>> degrees
>> to
>>> the motherboard.
>>>>
>>>> Great work on the board and I appreciate the time and effort you
>>>> put
>> into
>>> this and sharing it with all of us! I look forward to assembling the
>> boards
>>> when they arrive.
>>>>
>>>> Cheers,
>>>> -Mike
>>>>
>>>> -----Original Message-----
>>>> From: "Zippster" <zippster278 at gmail.com>
>>>> Sent: Friday, October 3, 2014 11:53am
>>>> To: "CoCoList for Color Computer Enthusiasts"
>>>> <coco at maltedmedia.com>
>>>> Subject: Re: [Coco] video composite on korean coco 26-3134A
>>>>
>>>> There was when it was sent, not sure what’s stripping them out.
>>>>
>>>> I’ll list them this way
>>>>
>>>> https://sites.google.com/site/thezippsterzone/home/coco2-projects
>>>>
>>>> https://oshpark.com/shared_projects/lHtMJ67Z
>>>>
>>>> -Ed
>>>>
>>>>
>>>> On Oct 3, 2014, at 10:48 AM, Al Hartman <alhartman6 at optonline.net>
>> wrote:
>>>>
>>>>> There's no link in that message...
>>>>>
>>>>> -[ Al ]-
>>>>>
>>>>> -----Original Message----- From: Zippster
>>>>> Sent: Friday, October 03, 2014 10:34 AM
>>>>> To: CoCoList for Color Computer Enthusiasts
>>>>> Subject: Re: [Coco] video composite on korean coco 26-3134A
>>>>>
>>>>> Hey guys,
>>>>>
>>>>> You may have missed my earlier post. I did a version of this
>>>>> circuit
>> in
>>> Eagle.
>>>>> Sound output is included.
>>>>>
>>>>> The files are in the zip on this page. CoCo2 Projects (Tandy
>>>>> Color Computer 2) - The Zippster Zone
>>>>>
>>>>> I put it up as a shared project on OSHPark. OSH Park ~ Coco2
>>>>> Composite Out (Type 01) Rev 03
>>>>>
>>>>> I laid the board out to replace the RF modulator in my Korean
>>>>> CoCo2’s, but as long as you get the signals to it, you could mount
>>>>> it
>>> anywhere.
>>>>>
>>>>> -Ed
>>>>>
>>>>>
>>>>> On Oct 3, 2014, at 7:20 AM, Michael Rowen <mike at borncoco.com> wrote:
>>>>>
>>>>>> John is indeed correct. I have built the simple circuit that
>>>>>> includes
>> a
>>> 1372 that connects to the signal from the 6847. It works well on
>>> every monitor I've used with a CoCo 2. The circuit is in the data
>>> sheet for the 6847. I have not had the time to create a PCB with
>>> Eagle. Some CoCos have the 6847 socketed, so it would be easy to
>>> make a board that plugs into
>> that
>>> 40 pin socket, with the 6847 plugging into the board. CoCo 2s with a
>>> soldered 6847, would require 7-8 clip leads, but can be done. I have
>> bread
>>> boarded this on a CoCo 2. This was the same method used by the
>>> Colorware adapter. I scored one of these at last year's CoCo fest.
>>> Its circuit uses more caps, but the principle is the same. I have
>>> not found any
>> significant
>>> quality differences using the reference circuit. Clean and sharp.
>>> Any
>> Eagle
>>> experts with some time on their hands to create the PCB files?? :)
>>> It
>> will
>>> probably be Christmas time before I get the chunk of time to tackle
this.
>>> I'm a newbie with Eaglecad. I'll try to post a video this weekend.
>>>>>>
>>>>>> Cheers,
>>>>>> Mike Rowen
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> "John W. Linville" <linville at tuxdriver.com> wrote:
>>>>>>
>>>>>>> NTSC CoCo2's use a modulator that does _not_ take a composite
>>>>>>> video input.
>>>>>>>
>>>>>>> The 6847 outputs signals called Y, phiA, and phiB. These are
>>>>>>> (very) roughly analogous to the YIQ signals that form a
>>>>>>> composite
>> video
>>> signal.
>>>>>>> A Motorola 1372 chip is used to combine those signals into
>>>>>>> something useful. The 1372 chip can produce either a baseband
>>>>>>> composite video signal or (by use of an RF tank circuit) a
>>> TV-compatible radio signal.
>>>>>>>
>>>>>>> On the Coco1, the 1372 only produced a composite video signal
>>>>>>> that was then fed (along with the audio signal) to an off the
>>>>>>> shelf RF modulator. On the CoCo2, the 1372 chip is only
>>>>>>> included as part of the RF modulator itself. The Y, phiA, and
>>>>>>> phiB signals go straight to the modulator where the RF-equipped
>>>>>>> 1372 turns them into a TV
>>> signal.
>>>>>>>
>>>>>>> I'm not sure if there is a pristine composite video signal
>>>>>>> available anywhere inside the RF modulator on a CoCo2. I was
>>>>>>> never able to find one, FWIW. You probably need to pull the
>>>>>>> modulator and build a new 1372-based circuit to replace it.
>>>>>>>
>>>>>>> Good luck!
>>>>>>>
>>>>>>> John
>>>>>>>
>>>>>>> P.S. It sounds like the PAL CoCo2 might be designed more like
>>>>>>> the
>>>>>>> CoCo1 in this regard. Of course, that only helps you if you are
>>>>>>> using a PAL CoCo2... :-)
>>>>>>>
>>>>>>> On Thu, Oct 02, 2014 at 09:56:31PM +0200, didier derny wrote:
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> I tried but no success...
>>>>>>>>
>>>>>>>> I don’t have any image on tv (connected to the antenna) No idea
>>>>>>>> if the coco 2 is broken or if my tv is unable to process the
>>>>>>>> signal
>>>>>>>>
>>>>>>>> With the oscilloscope I've not been a able to find a composite
>>>>>>>> signal Inside the modulator...
>>>>>>>>
>>>>>>>> Any idea ?
>>>>>>>>
>>>>>>>> Thanks
>>>>>>>>
>>>>>>>>
>>>>>>>> --
>>>>>>>> didier
>>>>>>>>
>>>>>>>> -----Message d'origine-----
>>>>>>>> De : Coco [mailto:coco-bounces at maltedmedia.com] De la part de
>>>>>>>> Simon Jonassen Envoyé : samedi 27 septembre 2014 16:26 À :
>>>>>>>> 'CoCoList for Color Computer Enthusiasts'
>>>>>>>> Objet : Re: [Coco] video composite on korean coco 26-3134A
>>>>>>>>
>>>>>>>> Hey....
>>>>>>>>
>>>>>>>> I did mine by tapping into the feeds that go directly to the rf
>>>>>>>> modulator....
>>>>>>>>
>>>>>>>> A couple of shielded wires soldered on to the pins and 2 rca
>>>>>>>> jacks on the rear of the case (audio/video)
>>>>>>>>
>>>>>>>> Works fine... No extra components needed (PAL machine)...
>>>>>>>>
>>>>>>>> /Simon :-)
>>>>>>>>
>>>>>>>>
>>>>>>>> -----Oprindelig meddelelse-----
>>>>>>>> Fra: Coco [mailto:coco-bounces at maltedmedia.com] På vegne af
>>>>>>>> didier derny
>>>>>>>> Sendt: 27. september 2014 13:23
>>>>>>>> Til: 'CoCoList for Color Computer Enthusiasts'
>>>>>>>> Emne: [Coco] video composite on korean coco 26-3134A
>>>>>>>>
>>>>>>>> Hi
>>>>>>>>
>>>>>>>> Is there an easy way to get a video composite signal on this
>> machine ?
>>>>>>>>
>>>>>>>> I guess a video composite signal or something approaching
>>>>>>>> should be found Somewhere near the modulator or inside the
modulator ?
>>>>>>>>
>>>>>>>>
>>>>>>>> Thanks
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> --
>>>>>>>> Coco mailing list
>>>>>>>> Coco at maltedmedia.com
>>>>>>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>>>>>> -----
>>>>>>>> Ingen virus fundet i denne meddelelse.
>>>>>>>> Kontrolleret af AVG - www.avg.com
>>>>>>>> Version: 2012.0.2247 / Virusdatabase: 4031/7782 - Udgivelsesdato:
>>>>>>>> 27-09-2014
>>>>>>>>
>>>>>>>>
>>>>>>>> --
>>>>>>>> Coco mailing list
>>>>>>>> Coco at maltedmedia.com
>>>>>>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>>>>>>
>>>>>>>>
>>>>>>>> --
>>>>>>>> Coco mailing list
>>>>>>>> Coco at maltedmedia.com
>>>>>>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> John W. Linville Someday the world will need a hero, and you
>>>>>>> linville at tuxdriver.com might be all we have. Be ready.
>>>>>>>
>>>>>>> --
>>>>>>> Coco mailing list
>>>>>>> Coco at maltedmedia.com
>>>>>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>>>>
>>>>>> --
>>>>>> Coco mailing list
>>>>>> Coco at maltedmedia.com
>>>>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>>>
>>>>>
>>>>> --
>>>>> Coco mailing list
>>>>> Coco at maltedmedia.com
>>>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>>>
>>>>> --
>>>>> Coco mailing list
>>>>> Coco at maltedmedia.com
>>>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>>
>>>>
>>>> --
>>>> Coco mailing list
>>>> Coco at maltedmedia.com
>>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>>
>>>>
>>>>
>>>> --
>>>> Coco mailing list
>>>> Coco at maltedmedia.com
>>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>
>>>
>>> --
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>>
>>>
>>> --
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>
>>
>> --
>> Coco mailing list
>> Coco at maltedmedia.com
>> https://pairlist5.pair.net/mailman/listinfo/coco
>>
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco
--
Coco mailing list
Coco at maltedmedia.com
https://pairlist5.pair.net/mailman/listinfo/coco
More information about the Coco
mailing list