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VGA to TV without TV-out

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gulson

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vga to tv schematic

With this easy circuit, you can connect your PC to TV without TV-out in graphic card.
Everything what you need is software called Power Strip for change resolution to 720x576, horizontal frequency: 15,625kHz, vertical frequency: 50Hz.
for external power supply 5V (optional) need disconnect Z1

Schematic
VGA pinouts
SCART pinouts
 

gulson

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ad724 scart

yes exactly! AD725 converts signal to PAL and You don't must use SCART (EURO)

however the circuit is more complicated and I think AD725 is in SMD package :(
 

K

kaeres

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vga to rca pin schema

Uuu, it`s so complicated :(
Please tell me how to mod this cable from SCART side.
One more time. How to connect the cable (3 wires inside him) to the euro pins on this picture
Whitch pins must be connected with s-video.
 

meax98

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mc 1377 vga tv

Connect like this:

21 pin SCART male: 4 pin SVHS male:

pin 17 (Composite ground) - pin 1 (Y ground)
pin 13 (RGB red ground) - pin 2 (C ground)
pin 19 (Composite video out) - pin 3 (Y luminance)
pin 15 (RGB red in) - pin 4 (C chrominance)

If you have only 3 pins in cable, then connect two grounds (pins 17,13,1 and 2) together.

I hope this will help you!

regards
meax98
 

K

kaeres

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vga to scart edaboard

Thank you very much. Maybe this well help. Ehh, this pro from service :D
 

joebazoka

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redukcia vga to scart schema

I don´t have TV with SCART connector. Here in SouthAmeric the TV have RCA connector. Is possible convert the Gulson circuit to tv without the pin 19 of SCART connector?. My intention is convert out signals of this circuit in RCA composite video. Please say me if this is possible. Regards.
 

SphinX

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vga to tv mc1377

Hi,

I have the same problem too.

Pharaoh Of Egypt
 

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kaeres

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vga to tv without vga

meax98 - the guy in the serwice says - this will work only if my tvout is video. I have s-video and it`s not working - he says.
It`s true ?
 

sa007jbond

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mc1377 vga to s-video

Hi,
How I see this adapter can connect
PC from VGA RGB connector to TV SCART RGB connector.

I wanted some hardware or PC video card which can use for INPUT
CGA or TV RGB signal and display it on PC in one window and capture it.

This can VIDEO BLASTER but only with input VIDEO signal. This isn't good enough. I wanted only solution with RGB input.

Is it possible?

Regards
 

C

CoOljack

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vga to tv out circuit

Zrobilem Ten kabel i nie moge zlapac odpowiedniego odswierzania. Tj. za bardzo nie wydzodzi mi obsluga tego progrmau Power Strip. Jak ustawiam 50 Hz w pionie to w poziomie mam 32, a jak ustawiam poziom na 16 to pion mam 29!
nie wiem co robic?
 

SphinX

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shema mc 1377

What that !
 

powerm

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schema vga to rca

8O Is the quality good?
 

meax98

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ad724 circuit

I didn't answer, because I tried all this circuits for myself and after two days of playing I got all clear. First easy part:

@kaeres:
Circuit will work, don't care what service people say. If you have S-video then take this circuit and convert that to Composite video (RCA connector). In this message http://www.elektroda.pl/eboard/viewtopic.php?t=32390&highlight= lokk at schematic SVHA-RCA.jpg. That is what you need.

@joebazoka, Pharaoh of Egypt:
If you don't have SCART connector then we must modify this circuit, because we can't just "pass" R,G and B signals to composite video like we did at previous schematic. We can feed composite video (RCA) to SCART, but in this case vice versa is not possible. So I tried to solve this and come up with two solutions:
a) Motorola MC1377P (works for color PAL and NTSC)
b) Analog Devices AD722/AD724 (works for color PAL and NTSC)

This is the component list for schematic with MC1377P:

1 DB15P male VGA plug
1 multi-wire cable (I used 8 wires+shield) to connect the VGA to the circuit
box.
1 box (metalic is better, though a plastic one is cheaper, and it's the one
I also used). This holds the circuit. The box is 13cm x 5.5cm x 2.5 cm
(W x D x H).
1 female panel-mountable RCA plug
1 male PCB mountable DC socket
2 male RCA plugs (for the connecting cable)
1 75ê cable, to connect the box to the input equipment. You can probably get
one of these in a shop somewhere. In that case, disregard the 2 male RCAs
above. I used a 50ê cable (by mistake), but it's quite okay. Just don't
use plain audio cable for this. It's AWFUL...
1 12VDC power supply. The circuit I made is only regulated for 5V. The chip
itself (MC1377) has an internal 8.5V regulator. Thus, you can plug in from
about 10V to 14V, unregulated power supply. This means a 9VDC transformer
can be used. I do. The chip needs 60mA maximum, but I haven't determined
the entire circuit supply current needs.

1 Motorola MC1377P chip
1 DIP-20 socket, for the chip
1 7805 5V PS regulator
2 BC547 transistors
1 Philips 330ns delay-line. These are H-A-R-D to find. Motorola suggests a
400ns delay line, though it seems 330ns are more common here in Europe.
Best place to look for one of these things, is inside a TV. The Philips
one is green, and about the size of your thumb (1 inch). I have seen 3 so
far, including the one I have. I have seen 2 other, being used in 2
Elektor Magazine projects. You can try your local TV repair shop. Beware
that some folks don't even know what this is, so be patient...
The impedance on these delay lines is 1Kê. Motorola advises that it falls
between 1Kê and 1.5Kê.
1 chroma bandpass transformer. This one's a little hard to tell what it is.
If you don't know diddley about this, it's one of those things inside the
TV that you turn round and around, which have a lot of wires around them.
About 1 cm high. For details on skiping this, refer to the MC1377P
datasheet. But you can probably get one of your electronics-skilled
friends to built one for you. Here's the details.

The transformer itself is 15mm high, plus 3.5mm for the pins, which are
0.7mm in diameter. Has 2 windings, and each one takes 60 turns of #38 AWG
wire (0.1 m/m).
Unloaded Q (Pins 1-3): 15 @ 2.5Mhz. Inductance: 30æH ñ 10% @ 2.5Mhz.

Bottom view:
___________
/ \
³ 3 -\ /-4 ³ --------
³ / \ ³ ^
³ 2 \ S / S ³ 7 ñ 0.2mm
³ / / ³ v
³ 1 - \- 5 ³ --------
\___________/

1 4.43Mhz crystal, just like the ones found on TVs. 4.43Mhz is the PAL color
carrier frequency. NTSC is 3.58Mhz, so you should get the appropriate one
for you.

Resistors:

1 trimmer, 47Kohm
4 75ohm
3 47ohm
3 1.8Kohm
1 2.7Kohm
1 33Kohm
1 3.3Kohm
2 1Kohm
1 220ohm

Capacitors:

1 trimmer 5pF-25pF (doesn't matter much, get one around this)
1 100uF, 16V (or more V)
1 10uF, 25V
4 100nF
1 12pF
2 1nF
2 10nF
2 180pF
1 33pF (NTSC: 47pF)
1 62pF (NTSC:100pF)
3 22uF


This is datasheet for Analog Devices AD722/AD724 and schematic for RGB to PAL/NTSC composite video.

I will try to send as much as possible data and theory about this project. Because, I have some problems with TV picture on some resolutions, on others not. Some cards (Matrox) are working better than others ...

regards
meax98
 

meax98

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vga timing 50hz

kaeres,
I'm very glad to hear that. Have a nice time watching your tv and send my regards to service people!

regards
meax98
 

G

gamin_

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vga out to tv without tv-out

Is this option available in demo version?
I can't change the 720*576 resolution in this software. -> I can't change the vertical / horizontal refresh ratio

can someone help me?

I had an other pb with this schematic there is no 5V available on pin 9 of the VGA connector.
I have to use an external 5V power supply.

Regards,
 

gamin

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vga to rca tv schematic

Is this option available in demo version?
I can't change the 720*576 resolution in this software. -> I can't change the vertical / horizontal refresh ratio

can someone help me?

I had an other pb with this schematic there is no 5V available on pin 9 of the VGA connector.
I have to use an external 5V power supply.

Regards,

PS: sorry for this second post but I forgot to login yesterday evening.
 
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