S-Video hack for DTV converter box?

[DaveC]

I like the programmable feature of the DTV Pal (Dish Network) converter box.
The one drawback is that it doesn't output S-Video.

I haven't received it yet, so I can't crack it open and give component
specifics but are the video chips that are common in these boxes capable of
both composite and S-Video output? Is it likely that only a connector and a
bit of wire is all that is needed for a slightly better signal output?

Thanks,
--
DaveC
me@bogusdomain.net
This is an invalid return address
Please reply in the news group

 

[Bill R]

DaveC wrote:

I like the programmable feature of the DTV Pal (Dish Network) converter box.
The one drawback is that it doesn't output S-Video.

I haven't received it yet, so I can't crack it open and give component
specifics but are the video chips that are common in these boxes capable of
both composite and S-Video output? Is it likely that only a connector and a
bit of wire is all that is needed for a slightly better signal output?

Thanks,

It would be much simpler to buy a composite to s-video adapter. Places
like MCM Electronics sell them for $4.99 (part number 33-0001 for the
"S" male to RCA female version).
--
Bill R.


e-mail address disguised to reduce spam

 

[Joel Koltner]

"Bill R" <nospam_brosenx@iglou.com> wrote in message
news:499dcd62$0$2698$d94e5ade@news.iglou.com...

It would be much simpler to buy a composite to s-video adapter.

Yeah, but then the image quality is no better than the original composite
signal. For a larger TV set, this difference is noticeable.

 

[John E.]

Yeah, but then the image quality is no better than the original composite
signal. For a larger TV set, this difference is noticeable.

Yeah, the whole purpose for adding a S-Video connector isn't for convenience,
but to get the video signals (ie separate Y & C signals) "prior" to the
composite connector.
--
John English

 

[Greegor]

On Feb 19, 3:27 pm, "Joel Koltner" <zapwireDASHgro...@yahoo.com>
wrote:

"Bill R" <nospam_bros...@iglou.com> wrote in message

news:499dcd62$0$2698$d94e5ade@news.iglou.com...

It would be much simpler to buy a composite to s-video adapter.

Yeah, but then the image quality is no better than the original composite
signal.  For a larger TV set, this difference is noticeable.

Is/was S-video ever really better quality signals than Composite
video?
My impression is that converting between the two was only a
matter of routing the right pin.

Was the alleged higher quality (S-Video over composite)
by virtue of the type of cabling as opposed to the
signal sent through it?

http://www.mcmelectronics.com/product/DISTRIBUTED-BY-MCM-RGB-322G-/33-0001

$7.89

Features:
This high quality adaptor converts composite video to S video and S
video to composite video. With a male S VHS connector on one end and a
female RCA type connector on the other (#33-0001), only a standard RCA
type video cable is required for connection or you can match the S-
video adaptor to your cables. The adaptor measures only 13/4" long and
1/2" in diameter allowing it to plug directly into the equipment and
solves the problems associated with mixing composite and S–video
inputs and outputs.
Note: This unit is a passive device and although it will allow
composite video signals to be used in S video inputs the signal will
remain the quality of composite video.

 

[Adrian C]

Greegor wrote:

Is/was S-video ever really better quality signals than Composite
video?

Yes.

My impression is that converting between the two was only a
matter of routing the right pin.

http://www.epanorama.net/circuits/svideo2cvideo.html

Was the alleged higher quality (S-Video over composite)
by virtue of the type of cabling as opposed to the
signal sent through it?

Nope.

http://www.mcmelectronics.com/product/DISTRIBUTED-BY-MCM-RGB-322G-/33-0001

$7.89

Expensive for a single cap.

--
Adrian C

 

[Dave Platt]

In article <7068obFn3kcpU1@mid.individual.net>,
Adrian C <email@here.invalid> wrote:

Is/was S-video ever really better quality signals than Composite
video?

Yes.

My impression is that converting between the two was only a
matter of routing the right pin.

http://www.epanorama.net/circuits/svideo2cvideo.html


Was the alleged higher quality (S-Video over composite)
by virtue of the type of cabling as opposed to the
signal sent through it?

Nope.

S-Video sends the color (chroma) and brightness (luminance)
information separately. Composite video sends them both as part of
the same electrical signal.

A TV or monitor needs to deal with chroma and luminance separately in
order to produce a color picture. If they're sent separately (via
S-Video) they're pretty much ready to use. If they're sent together
(as a composite signal) the TV has to separate them before using them.

Unfortunately, the chroma and luminance parts of a composite-video
signal actually overlap (in the frequency domain). This makes it
difficult for the TV to separate them cleanly - the process of
filtering one out of the other tends to create artifacts (e.g. "dot
crawl" at brightly-lit edges).

Many video-source devices (e.g. digital set-top boxes) can and do
create the chroma and luminance signals separately. Sending them to
the TV via separate wires, and avoiding the "combine them, and then
filter them apart" step, eliminates the artifacts-of-filtering-them-
apart, and thus gives you a better-looking image.

--
Dave Platt <dplatt@radagast.org> AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

 

[G-squared]

On Feb 19, 2:06 pm, Greegor <Greego...@gmail.com> wrote:

On Feb 19, 3:27 pm, "Joel Koltner" <zapwireDASHgro...@yahoo.com
wrote:

"Bill R" <nospam_bros...@iglou.com> wrote in message

news:499dcd62$0$2698$d94e5ade@news.iglou.com...

It would be much simpler to buy a composite to s-video adapter.

Yeah, but then the image quality is no better than the original
composite
signal.  For a larger TV set, this difference is noticeable.

Is/was S-video ever really better quality signals than Composite
video?
My impression is that converting between the two was only a
matter of routing the right pin.

Was the alleged higher quality (S-Video over composite)
by virtue of the type of cabling as opposed to the
signal sent through it?

Yes - provided there was sufficient bandwidth of he components

http://www.mcmelectronics.com/product/DISTRIBUTED-BY-MCM-RGB-322G-/33...

$7.89

Features:
This high quality adaptor converts composite video to S video and S
video to composite video. With a male S VHS connector on one end
and a
female RCA type connector on the other (#33-0001), only a standard
RCA
type video cable is required for connection or you can match the S-
video adaptor to your cables. The adaptor measures only 13/4" long
and
1/2" in diameter allowing it to plug directly into the equipment
and
solves the problems associated with mixing composite and S–video
inputs and outputs.
Note: This unit is a passive device and although it will allow
composite video signals to be used in S video inputs the signal
will
remain the quality of composite video.

The worst thing to happen to composite video is to mix the cubcarrier
onto the 'Y' channel because separating them out can bve real easy
(cheap trap, poor performance) or difficult (expensive comb). The
cheapy adaptor isn't even a trap in that there is still subcarrier on
the 'Y' channel. The best separators are the digital 3 line combs
which some of the expensive TVs have in them. They come _very_ close
to component but cost more.

G˛

 

[DaveC]

Thanks, guys.

But i'm talking about a soldering iron hack. I guess what I want to know is
whether the Y and C signals are commonly available on pins of a video chip
used in many of these TV converter boxes. I have no qualms about running
conductors from pins on an IC to an epoxied-in S-video connector.
--
DaveC
me@bogusdomain.net
This is an invalid return address
Please reply in the news group

 

In alt.engineering.electrical Bill R <nospam_brosenx@iglou.com> wrote:
| DaveC wrote:
|> I like the programmable feature of the DTV Pal (Dish Network) converter box.
|> The one drawback is that it doesn't output S-Video.
|>
|> I haven't received it yet, so I can't crack it open and give component
|> specifics but are the video chips that are common in these boxes capable of
|> both composite and S-Video output? Is it likely that only a connector and a
|> bit of wire is all that is needed for a slightly better signal output?
|>
|> Thanks,
|
| It would be much simpler to buy a composite to s-video adapter. Places
| like MCM Electronics sell them for $4.99 (part number 33-0001 for the
| "S" male to RCA female version).

The whole point of S-video is to avoid ever combining the Y and C signals in
the first place, because it is so hard to separate them. You might as well
let the TV's composite input separate them, unless the composite to S-video
converter you get is a "perfect" design (and this would be very expensive).

--
|WARNING: Due to extreme spam, googlegroups.com is blocked. Due to ignorance |
| by the abuse department, bellsouth.net is blocked. If you post to |
| Usenet from these places, find another Usenet provider ASAP. |
| Phil Howard KA9WGN (email for humans: first name in lower case at ipal.net) |

 

On Feb 19, 6:45 pm, DaveC <m...@bogusdomain.net> wrote:

Thanks, guys.

But i'm talking about a soldering iron hack. I guess what I want to know is
whether the Y and C signals are commonly available on pins of a video chip
used in many of these TV converter boxes. I have no qualms about running
conductors from pins on an IC to an epoxied-in S-video connector.
--
DaveC
m...@bogusdomain.net
This is an invalid return address
Please reply in the news group

It depends on exactly which chip is used for the output of the box.
Datasheets are often availalble for many chips on-line as freebies.
There are almost always examples of how to use the chip which would
likely include S-video if the chip is capable of it. So, it's time to
peel off the lid and tell us what chips are actually in the box.

G˛

 

[DaveC]

So, it's time to
peel off the lid and tell us what chips are actually in the box.

When it arrives, I'll do that.

Thanks,
--
DaveC
me@bogusdomain.net
This is an invalid return address
Please reply in the news group

 

[Tomi Holger Engdahl]

Greegor <Greegor47@gmail.com> writes:

On Feb 19, 3:27 pm, "Joel Koltner" <zapwireDASHgro...@yahoo.com
wrote:
"Bill R" <nospam_bros...@iglou.com> wrote in message

news:499dcd62$0$2698$d94e5ade@news.iglou.com...

It would be much simpler to buy a composite to s-video adapter.

Yeah, but then the image quality is no better than the original composite
signal.  For a larger TV set, this difference is noticeable.

Is/was S-video ever really better quality signals than Composite
video?

Yes S-video is technically better and in real life usually noticeable
better than composite video. Especially when the the video source
and/or receiver side are not up to be best "professional video"
quality, the composite video picture quality is often not the
best possible and S-video is considerably sharper especialy on
demandign material (for example computer screen graphics to TV).
Very good professional video equipment can work with composite
video signal from cameras so well that it is hard to tell if
composite video or S-video interface is used.

My impression is that converting between the two was only a
matter of routing the right pin.

It is more than that.
Converting from S-video to composite video is just matter of
combining signals from two pins on S-video connector to
one signal pin on composite video connector. Simplest
as simple as this
http://www.epanorama.net/circuits/svideo2cvideo.html

Y-ground------------------+
+---------- RCA/composite ground
C-ground------------------+

Y-------------------------+
+--------- RCA/composite video
C------------||-----------+
470pF

The opposite direction, from composite video to S-video, with
good image quality is much much more complicated.
It can be done with some passive filtering circuitry with
not very optimal picture quality (needs different component
values for PAL and NTSC video standards). Very good quality
will need pretty complicated signal processing circuitry.

Was the alleged higher quality (S-Video over composite)
by virtue of the type of cabling as opposed to the
signal sent through it?

http://www.mcmelectronics.com/product/DISTRIBUTED-BY-MCM-RGB-322G-/33-0001

$7.89

Features:
This high quality adaptor converts composite video to S video and S
video to composite video. With a male S VHS connector on one end and a
female RCA type connector on the other (#33-0001), only a standard RCA
type video cable is required for connection or you can match the S-
video adaptor to your cables. The adaptor measures only 13/4" long and
1/2" in diameter allowing it to plug directly into the equipment and
solves the problems associated with mixing composite and S–video
inputs and outputs.
Note: This unit is a passive device and although it will allow
composite video signals to be used in S video inputs the signal will
remain the quality of composite video.

I have my doubts on the quality it can do the composite video to S video
conversion. With such passivode converter the result could
be anything from not so good to useable, but never "crystal clear".
With good quality equipment that has composite video input
and S-video inputs, wiring the composite vidoe signal to composite
video input will give you better image quality than with passive
composite video to S-video converter to S-video input.
The best image quality would be available if you can get S-video
from your signal source to S-video input on display device
(or some even better video interface if you have such option).

--
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at
http://www.epanorama.net/

 

[GMAN]

In article <499dcd62$0$2698$d94e5ade@news.iglou.com>, Bill R <nospam_brosenx@iglou.com> wrote:

DaveC wrote:
I like the programmable feature of the DTV Pal (Dish Network) converter box.
The one drawback is that it doesn't output S-Video.

I haven't received it yet, so I can't crack it open and give component
specifics but are the video chips that are common in these boxes capable of
both composite and S-Video output? Is it likely that only a connector and a
bit of wire is all that is needed for a slightly better signal output?

Thanks,

It would be much simpler to buy a composite to s-video adapter. Places
like MCM Electronics sell them for $4.99 (part number 33-0001 for the
"S" male to RCA female version).

While easier, that is just "not" the same thing.

 

[GMAN]

In article <d6927bfa-1148-4ebb-8803-2bfc3cf6f4a5@i24g2000prf.googlegroups.com>, Greegor <Greegor47@gmail.com> wrote:

On Feb 19, 3:27=A0pm, "Joel Koltner" <zapwireDASHgro...@yahoo.com
wrote:
"Bill R" <nospam_bros...@iglou.com> wrote in message

news:499dcd62$0$2698$d94e5ade@news.iglou.com...

It would be much simpler to buy a composite to s-video adapter.

Yeah, but then the image quality is no better than the original composite
signal. =A0For a larger TV set, this difference is noticeable.

Is/was S-video ever really better quality signals than Composite
video?

Are you kidding? Of course it was in MOST circumstances.

 

On Thu, 19 Feb 2009 13:10:00 -0800, DaveC <me@bogusdomain.net> wrote:

I like the programmable feature of the DTV Pal (Dish Network) converter box.
The one drawback is that it doesn't output S-Video.

I haven't received it yet, so I can't crack it open and give component
specifics but are the video chips that are common in these boxes capable of
both composite and S-Video output? Is it likely that only a connector and a
bit of wire is all that is needed for a slightly better signal output?

Thanks,

There is a list of converters with S-video here:
http://www.ezdigitaltv.com/Additional_Features_Matrix.html

John