RGB to SVIDEO with A-22 Converter

[Kakaboy]

Originally Posted by cosmicfrog

hahahah Z you been spoil`d with all ya fanci toys

just desolder the bloody thing and store it away somewhere where you will never look again

LOL

[Kakaboy]

Hey Zetro can you see if there is anything wrong with my setup ?
I have connected to TV but get no signal . I tested the +5v and its fine .
The ceramics they did not have but gave me the next equivelant the only one im not sure about is the 33ohm resistor . can someone check and see if its enough .

The only other thing is the Y&C on the S-video pinout maybe round the wrong way but not sure .

[Zetr0]

@Karl

I think you have your 100uf radial caps are round the wrong way. hence they are blocking Y and C signal instead of cleaning it.

thats my first take... just cooking dinner for the girls will have a closer look in a smidge


also tripple check the transistor orientation.

[Kakaboy]

Originally Posted by Zetr0

@Karl

I think you have your 100uf radial caps are round the wrong way. hence they are blocking Y and C signal instead of cleaning it.

thats my first take... just cooking dinner for the girls will have a closer look in a smidge


also tripple check the transistor orientation.

I am such a NOOB Zetro . I couldnt be more of an electronics novice if I tried . I guess little projects like this fast track me into the land of knowledge .

I assumed the white stripe on the cap was to highlight (+) and never even noticed there is a BIG (-) printed on the strip

I have checked the transistors and placed the flat side where you have the black line in the diagram (_) .

When I get home I will turn the caps around hopefully I havent damaged them .

Thanks Zetro once again you are a legend

[Zetr0]

no worries good luck on your project

I will say that no matter what you do, ALWAYS check a components data sheet and if need be revise the schematic =)

Transistors have a Base signal [ B ] - A Collector [ C ] and an Emmit [ E ], their orientation pending on some brands and package types may change so input your component number at the above address and Download or View PDF datasheet for that specific component.

good luck and if there are need for corrections in the schematic then please put them up here.

[Kakaboy]

Originally Posted by Zetr0

no worries good luck on your project

I will say that no matter what you do, ALWAYS check a components data sheet and if need be revise the schematic =)

Transistors have a Base signal [ B ] - A Collector [ C ] and an Emmit [ E ], their orientation pending on some brands and package types may change so input your component number at the above address and Download or View PDF datasheet for that specific component.

good luck and if there are need for corrections in the schematic then please put them up here.

Will do Z ,

Appreciate your feedback will double check transistors again and redo the caps . Will report back soon .

Karl

[Kakaboy]

Hey Zetro ,

I have turned caps and still nothing . Not even a flicker . I have turned the transistors even thou I believe they were right and still nothing mine are ( 2N 3904 J16 ) which I cant seem to get a match for in data sheet . I have even swapped the Y & C just incase as im running out of ideas and still no go .

Is there something I am missing ? Should I get a picture straight out of the S-video board , should there be something else that needs to be done ?

Im at a loss atm .

[Anemos]

@kakaboy, good luck to your project ..
check the grounds again , and try to test on other TV if you have..

[Zetr0]

@Kakaboy

heres some help m8






=)

[Kakaboy]

Originally Posted by Anemos

@kakaboy, good luck to your project ..
check the grounds again , and try to test on other TV if you have..

I have GND connected to motherboard shield . Also have tried 2 LCD TV's with S-Video . When I turn on Amiga the picture on TV is completely unchanged no electrical disturbance or anything .

[Kakaboy]

@Zetro

On the 33ohm Resistor I have 460ohm . The guy in the shop ran out of 33ohm and asked me if higher is ok . Will the higher resistance be enough to kill the signal ?

Karl

[Anemos]

Originally Posted by Kakaboy

On the 33ohm Resistor I have 460ohm .

i think all resistors has wrong value .. if i see good, is 460Kohm and not 460ohm
check the colors and resistance there> http://samengstrom.com/nxl/3660/4_ba...e_page.en.html - http://samengstrom.com/nxl/10116/5_b...e_page.en.html

[Kakaboy]

Originally Posted by Anemos

i think all resistors has wrong value .. if i see good, is 460Kohm and not 460ohm
check the colors and resistance there> http://samengstrom.com/nxl/3660/4_ba...e_page.en.html - http://samengstrom.com/nxl/10116/5_b...e_page.en.html

Im at work atm so I cant see the picture properly . I am pretty sure the label on the packet said 4** something .

Im 100% the 10k are right and the other is 110somtheing . But deffinately the 33ohm is wrong . I will double check and put multimeter on the spares in the packet to see what they are .

I will have to go to different store and see if the got the right ones .

Just for interest why is there a resistor on the signal out ?

BTW thanks Zetro & Anemos for your help .

[rkauer]

460 is way too much. If you don't find a suitable 33 Ohm resistor, grab three 100 Ohm and put they in parallel (united by both ends at the same time). This will give you 33.33 Ohm.

BTW: 460??? The common value is 470.

[Kakaboy]

Originally Posted by rkauer

460 is way too much. If you don't find a suitable 33 Ohm resistor, grab three 100 Ohm and put they in parallel (united by both ends at the same time). This will give you 33.33 Ohm.

BTW: 460??? The common value is 470.

Thanks Rkauer,

Im not 100% on that . Im trying to read the bands from the picture above . These resistors have 5 bands , I think the 5th is quality probably doesnt mean much im not sure .

I am very green to electronics and I dont understand how 100ohm x 3 will make 33ohm ?

KArl

[kipper2k]

when i built mine i experimented with 100 ohm pots. You can get video up to the full 100 ohms but the brightness level will change. A value between 30 - 75 ohms should produce a workable signal. Each board is slightly different due to different component tolerances, thats why i used a variable 100 ohm pot to find an appropriate value for that particular board then replaced it with a fixed value resistor. I've built 5 and the value has differed between 30 - 75 ohm based on my video output preference

[Kakaboy]

@Kipper

So I can safely say that 4** is way too high . Thanks for your input mate .

[kipper2k]

here is a nice tool that tells you what the resistance of a resistor is by looking at the colour of the stripes.

http://www.csgnetwork.com/resistcolcalc.html

for example...

a resistor with a violet, green and black band will be 75 ohms. There is normally a gold or silver band on the end that indicates the tolerance from the specified value (5% if its gold)

Band 1 = first value
Band 2 = second value
Band 3 = multiplier of band 1 and 2 value by a factor of 10)
Band 4 = tolerance value


most resistors i have used don't have a band 3 value, and use band 3 as the multiplier but you can get resistors with a third band value.

[Kakaboy]

Ok the wife just called and related whats on the packet of suspect resistor . its 470K

[kipper2k]

wow, way out. I believe you guys have a digikey in Australia. If you want i can post you the part numbers for the resistors