HAMI 8" Mod: S-video input

[Megaman]

I'v got a 8" Hami lcd that got a/v and vga inputs. (Some versions got RF also). The menu where input source is selected however show three alternatives: vga, a/v and s-video. This made me wonder if s-video were supported but just missing the connector.

After spending a few hours looking in datasheets, guessing and measuring with my multimeter I got to the conclusion that it should be possible to add a s-video input. And so I did.

Here is some pictures of how.
Here is one of the connection on the controller pcb. The 3 pin connector and a capacitor were missing. I soldered cables to where the connector should go and moved a capacitor that were connected to an unused a/v input of the circuit. (It has support for several a/v and/or s-video channels).

 

[Megaman]

I had no s-video connector at home so i desoldered and modified an ps-2 connector from an old motherboard.

 

[Megaman]

Here is another picture of the connector:

 

[Megaman]

Here I have soldered the cables to the pcb, if you look close you can also see the (re)moved capacitor:

 

[I_eat_flowers]

hey megaman,

great job.
What capacity is the condensor you've removed?
I ask, coz ppl in Germany wanna know if they can insert one instead of remove and insert.

Is it possible to get the schematics?

IEF

 

[Megaman]

Unfortenately I did not measure the capacitance while I had it removed, so I don't know. I found it easier to move one instead of waiting a few days to be able to buy one.

As for the schematics, what do you want the schematics of?
The connection is just three cables.
The inputs comes in and goes through a 18 (or something like that) ohm resistor and then the capacitor in series. Then straight in to the chip.

 

[I_eat_flowers]

hi megaman,

the schematics will show the capacity of the capacitor, u know?

IEF

 

[Megaman]

Aha, schematic of the whole board. No I don't have anything like that and I doubt it wery much that you can get hold of one.
I just jused my multimeter and the ic-datasheet to get the information I needed.

 

[jesusjj86]

http://forum.aspect-geek.net/index.php?showtopic=5184

http://forum.aspect-geek.net/index.php?showtopic=5046

ed2k://|file|hami8001.MOV|10432552|506BE497A84205D8910DE6806F8D5AFC|h=FFDKEPE6US2YI6SNIHVQNBVQGCYMXJAR|/

this I complete a format video mov

 

[Megaman]

Looks like I'm not the first to do this. Too bad I don't understand french, could have saved me a few hours of work.

Seems like they use a 22nF capacitor.
Looking through the application information in the datasheet of the ic tells me it should be 47nF though.

 

[jesusjj86]

data

there are two types of the datasheet. are doos types of plate controller the one that has the chip tw9905, datasheet of tw9903 is compatible the legs. and the one of chip SAA7114H http://www.semiconductors.philips.com/pip/SAA7114H.html.
from which page you have removed datasheet? direction that can lower it and see it.

 

[Megaman]

from which page you have removed datasheet? direction that can lower it and see it

I don't understand what you mean here.

I used the datasheet for the SAA7114 that can be found here (or from the link you posted) http://www.semiconductors.philips.com/acrobat_download/datasheets/SAA7114_2.pdf
On the left (bottom) of page 82 you can see the interface and the capacitor and resistor values.

 

[jesusjj86]

I don't understand what you mean here.

I used the datasheet for the SAA7114 that can be found here (or from the link you posted) http://www.semiconductors.philips.com/acrobat_download/datasheets/SAA7114_2.pdf
On the left (bottom) of page 82 you can see the interface and the capacitor and resistor values.

thanks, I have been mistaken in post(y not to erase them or to publish them). already tapeworm the pdf.

 

[Guy Grotke]

results?

Have you tried to compare the picture, with A/V and S-video inputs? I can connect my satellite TV box to my video-to-VGA converter (that sends XVGA to my projector LCD), using either type of interface. With the S-video connection, the screen image looks MUCH better.

Can you give us the model number and specifications for your 8" Hami?

 

[jesusjj86]

the pdf for tw9903(pines compatible with tw9905 that my uses hami8001) this in emule(600k great) it is called:datasheet9903.pdf

ed2k://|file|datasheet9903.pdf|645629|A34347EE7439D7565739219BAC6DA61A|h=L743FITB5AONOV6TVEDL3LES3YERHRDA|/


the results in this type of controller,de moment are not good. image in b/n
in the forum frances est masters explained.

 

[jesusjj86]

Looks like I'm not the first to do this. Too bad I don't understand french, could have saved me a few hours of work.

Seems like they use a 22nF capacitor.
Looking through the application information in the datasheet of the ic tells me it should be 47nF though.

if, your you are right 47 he is ok(pero seems that with 22 also it works) in your type of controller.