[Coco] S-video Prospects...

[Stephen H. Fischer]

Hi,

In the first attack I had great difficulty in understanding how the wrong
statements could have been made, it took a long time to finally understand.

It has been many decades since I had a course in Analog Computing and then
at the start of the IC digital age there was not too much time spent even
then on Analog. I did well in almost all EE areas and understood Analog
computing just fine.

One of the lab experiments was to show that an IC could perform a "AND"
function, that being the state of the art at the time. They spent a lot of
time on tubes.

As the Digital world has grown to such size today, I suspect that Analog
Computing is still taking a back seat, perhaps not even a required part of
current EE studies.

The first incorrect statement had to been made by trying to understand how
the analog circuit works by applying the more well known digital processing
methods.

Analog computing is different from digital computing and has it's
limitations in different areas. The first attack stated a possible problem
that a purely digital solution might have a problem with.

The Analog AD 72x IC's are using analog processing even though parts of it
appear to be doing things using digital methods.

I must admit that the details of how the chips operates are more than I can
understand today as I am not following that area of electronics.

Never the less, I recognized an analog process in the description even
though my mind slipped into the digital world at first in trying to
understand what was being done. I then built an analog understanding. I was
able at that point to understand how someone with lots of digital knowledge
but not as good understanding of analog computing might not take the step to
an analog understanding and think that the analog AD72x had a digital
problem which it of course does not.

That attack posting was the only one made to the list and may have well shut
off postings by others.

A very glowing post was made to B.L.CoCo, one that if made to the list may
have started some of the positive discussion that are occurring now.

That's why I said that the interest in CoCo 3 to S-Video was ZERO, basing
that on the attack posting being the only comment made.

If you still believe that you are proving correct information, I am sorry
for your lack of understanding of electronics.

The CoCo is in the NTSC world as so much of electronics today are. That
world is very well understood and few if any EE's are allowed to make any
mistake at all because any errors can be recognized very early due to the
widespread knowledge of NTSC.

The AD72x was designed to accept input from the very well known NTSC world.
The CoCo is a correct member of that world.
There just cannot be any problem in connecting the two together.

Yes perhaps I have the only currently CoCo 3 operational version. I would
have to plug the wires back into the quick bread boarding block as the AD723
is in use every day converting the picture from my HTPC to my S-Video
television. Perhaps I would make a cable with the three 100 Ohm resistors
and eliminate the breadboard.

Yes I am waiting for someone to duplicate the circuit and announce that it
works just fine for them also. As there are no adjustments at all and
assuming that the circuit is built correctly I am sure that the same great
results will be obtained.

The AD73x was designed to perform a specific function, the exact same one
that I am using it for in both the HTPC and the CoCo 3 applications. The
exact function that it is being sold in large quantities to perform in a
very wide list of projects. As several versions have already been produced
and sold it appears to be a very profitable item.

We should be supporting any and all CoCo projects and not trying to kill
them which seems to be the motivation for these absurd attacks.

None of your comments have been useful except perhaps to continue the
negative tone that this list takes on too much of the time.

We need to spend more time helping people produce successful projects
instead of pointing out each and every possible problem.

Please be more careful showing your lack of understanding.

As to the cost, any price can be obtained, with my well stocked parts bin
and several electronic sources still open I think it is reasonable.

If you are trying to get a cost estimate by buying one of each quantity at a
store with high markups, then you will come up with a total that is very
high. We each have different resources.

Some of the prices quoted elsewhere appear to be high and some too low. As
to producing a product with SM parts made in China with a quantity of less
than ten I expect the $95 board to be cheaper. Quantity counts.


jdaggett at gate.net wrote:
> Well excuse me for pissing you off!
>
> While your little experiment seems to work on a vast sample of "ONE", I
> am not convince
> that your simple circuit is robust to work on many. Secondly I have
> stated two issues that
> are not false information. So if you think that they trivial then that is
> your choice. Granted I have not tried the AD725 in any circuit form so I
> cannot verify your claims. IF this is an anoyance to you then so be it. I
> will then be anoying. I have just issued some concerns from the
> specifications of both the AD725 and the Color Computer itself.
>
> Besides I think you far under estimate the material costs. The chip alone
> is $9 and a 16 pin surfboard is in the $6 range. Two items and you are
> already at $15. Now if one has a very
> well stocked parts bin then maybe $15 is realistic. I seriously doubt
> that the average person out there can do it for that cost.
>
>
>
> james
>
>
> On 4 Jan 2006 at 18:22, Stephen H. Fischer wrote:
>
> From:           "Stephen H. Fischer" <SFischer1 at MindSpring.com>
> To:             "CoCoList for Color Computer Enthusiasts"
> <coco at maltedmedia.com>
> Subject:        Re: [Coco] S-video Prospects...
> Date sent:      Wed, 4 Jan 2006 18:22:57 -0800
> Organization:   A. Nani Mouse Inx.
> Send reply to:  CoCoList for Color Computer Enthusiasts
> <coco at maltedmedia.com>
> <mailto:coco-request at maltedmedia.com?subject=unsubscribe>
> <mailto:coco-request at maltedmedia.com?subject=subscribe>
>
>> Hi,
>>
>> What!!! Another stupid reply. I am getting tired of these.
>>
>> Most people on this list know that statement is wrong.
>>
>> The CoCo 3 produces *exactually* what the AD72x chips are designed to
>> convert to NTSC S-Video.
>>
>> First is it was too fast or slow I forget, now this totally wrong
>> statement.
>>
>> Go stand in the corner for 3 hours with a dunce hat!
>>
>> Stephen H. Fischer
>>
>> jdaggett at gate.net wrote:
>>> Stephen
>>>
>>> One major problem with the AD72x series of chips is that they require
>>> RGB interlace signal. The Coco 3 is non-interlace RGB.
>>>
>>> james