Cheap RGB to Video converter for vintage computers | MSX Resource Center (Pagina 3/5)

Guardian (3571)

01-05-2015, 00:36

The boards finally arrived. The quality is good, but the bloody customs took 20% tax on my order.

http://www.finnov.net/~wierzbowsky/zefisha/realboard.jpg

Next is to assemble everything on this board and test again. Then I may be able to sell the boards or kits. According to my German friends I can't sell the assembled boards without applying for some sort of "recycling" permission. So no assembled boards, not officially at least.

Alexey

Van Wierzbowsky

Guardian (3571)

10-05-2015, 16:28

Finally both boards are assembled and tested. One board has 725 converter chip, the other - 724. Both boards use 1881 sync separator chip, other similar chips did not work (I will try to find out why). Here's the picture of assembled boards.

http://www.finnov.net/~wierzbowsky/zefisha/assembled.jpg

The 724 based board needs less parts, so it's slightly cheaper to make. The LED and its brightness control potentiometer may be skipped as well. Also either PAL or NTSC crystal may be skipped depending on your TV/Monitor's capabilities. On the 725 based board the Luma trap can be also skipped to save costs.

So if you are interested, please contact me and specify whether you need just the board, the board with all components or the board without certain components and connectors. I might sell the ready made board, but unofficially.

Alexey

Van ericb59

Paragon (1099)

11-05-2015, 06:45

what are exactly the specifications ?

Van gdx

Enlighted (6102)

11-05-2015, 10:04

Interesting, does it support japanese NTSC?

Van Wierzbowsky

Guardian (3571)

11-05-2015, 12:50

@gdx: Yes, it supports both PAL and NTSC signals from European and Japanese models of MSX. Also works with Atari and Amiga.

@ericb59: I am not sure how exactly the detailed specs should look like. This is my first electronics project. The converter accepts R+G+B+Composite (either pure CSync or composite video) or R+G+B+VSYNC+HSYNC signals and converts them to S-Video (Chroma+Luma) and Composite video (CVBS) signals. The converter is based on AD725/AD724 encoder and LM1881 sync separator chips so the exact specs are tied to those chips.

Van sd_snatcher

Prophet (3645)

18-06-2015, 01:39

Quote:

the bloody customs took 20% tax on my order.

Just 20%?! That sounds like a paradise to me. The Brazilian government will tax:

- 5% on any international purchase, over the financial transaction
- 60% or more on the customs. But the officer can decide to arbitrate how much he thinks the product is worth (instead of what's declared on the invoice) and then apply the taxes over that imaginary value. There are horror histories of people being taxed R$10000 (~€3000) for a mere kitchen sauce. Note: the minimum wage in Brazil is R$788 (~€227,30).

Van Wierzbowsky

Guardian (3571)

18-06-2015, 02:23

Yes, 20% is the tax for any purchase abroad. Beside here in Germany you pay 40% taxes on your income. Food, heating and living costs are very high. The average salary is 2000 euros, but the high expenses make all people live from hand to mouth. And many have loans they pay for decades. But at least your country is not occupued by USA...

Van gdx

Enlighted (6102)

18-06-2015, 07:40

Do you plan to make an S-Video & Composite Video to VGA or HDMI converter?

Van Wierzbowsky

Guardian (3571)

18-06-2015, 09:39

There is no point. There are a lot of cheap S-Video to VGA convertors on Ebay. The cheapest one is 14 euros. Maybe some day I will make an FPGA based RGB to HDMI converter. But I need to learn a lot first.

Van NYYRIKKI

Enlighted (6030)

18-06-2015, 10:40

@Alexey: You may also like to check out this post if you are into FPGA.