My first NBTV system

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My first NBTV system

Postby eyrope » Tue Jul 16, 2013 5:48 pm

Hello. My name is Michael, I'm 17 years old. I live in Russia. The chance to read online about a mechanical television and decided to do it with their hands. Disk made from vinyl records. Received the first image, but it's not what I expected. What I did wrong?
Image
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Postby DrZarkov » Tue Jul 16, 2013 8:01 pm

Привет Eyrope! Добро пожаловать сюда в этом форуме.
If that is the BBC "eye" testcard, the solution is easy: The signal is inverted. Just try another CD-Player or computer soundcard as source of the picture. If that is not possible for you: it is quite easy to invert the polarity, there are several suggestions on this website/forum to do so.
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Postby eyrope » Tue Jul 16, 2013 8:48 pm

Yes, this is the BBC "eye". Signal I'll try to invert. Now do another disk with apertures smaller diameter. I want to get a better picture.
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Postby eyrope » Wed Jul 17, 2013 12:04 am

I changed the polarity and the picture was much better. Thanks for the hint, I would not have thought of. Picture mirrored. Can I fix this? Still image leaves and in the middle is divided in half. Later I'll upload the pictures of the TV and describe in detail all.
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Postby eyrope » Wed Jul 17, 2013 5:39 am

Put amplifier in TV housing. Appeared grayscale, but the contrast and brightness still not enough to fully pictures. Looking through this forum, you have great images. I'm trying to do the same. Довольно интересное занятие:)
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Postby eyrope » Wed Jul 17, 2013 8:10 pm

The disc is made of vinyl and has 32 ​​holes. Template by which I did drive I made​​. Speed ​​control yet, but I want to connect the stepper motor to the computer and set the desired speed. The speed is adjusted manually. LED assembly of the torch. She stands in a metal box. Inside the box is made of foil reflector and diffuser in matte plastic. as an amplifier using a video board from the computer speakers. There was a contrast adjustment. Now, on the screen of my TV shows shades of gray and the picture became more detailing.

Image

Image

Image
eyrope
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Postby Andrew Davie » Wed Jul 17, 2013 10:25 pm

eyrope wrote:I changed the polarity and the picture was much better. Thanks for the hint, I would not have thought of. Picture mirrored. Can I fix this? Still image leaves and in the middle is divided in half. Later I'll upload the pictures of the TV and describe in detail all.


If you spin the disc the other way, your picture will no longer be mirrored.
Welcome aboard! Congratulations on your success :)
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Postby DrZarkov » Wed Jul 17, 2013 11:22 pm

>Довольно интересное занятие

That's why we are here! :lol:

To improve the greyscale/contrast I think there is no way around making your own video-driver instead of using an audio amplifier. Look in this forum for "Klaas 1 transistor video driver", there are several threads about it. It is very easy to make and with very good results.

I wonder if it would be possible to make a relative simple circuit around cheap russian valves like the 6C19N-B (in our letters: 6S19I-W), costs about 3 EUR, or the 2SH27L which is even cheaper and available in large quantities.
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Postby eyrope » Thu Jul 18, 2013 12:20 am

Я считаю видео драйвер цепи на форуме. Трубы, я не нахожу места. Хотя я постараюсь заказать по почте. Я живу в очень маленьком городке, и мы не имеем Radio Shack. Все детали взяты из демонтированного оборудования. Я уеду на несколько дней, все эксперименты пока приостановлено.
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Postby DrZarkov » Thu Jul 18, 2013 2:04 am

I understood you, but I answer in English, as my russian is not that good. I know that problem living in a small village, you have to order everything via the internet. When I was twelve and developed first interest in mechanical TV I wish there was something like the internet... But improvising was always a speciality of russian engineers, and they've made very reliable and good working things, even without getting always the right parts. .)


Which circuit did you use? You wrote it is from the forum, on the picture it looked like an audio amplifier.

You can find russian valves worldwide at Ebay or here in Germany in some shops like Oppermann Elektronik, who also have a webshop.
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Postby eyrope » Thu Jul 18, 2013 2:34 am

The photo below is an amplifier of computer speakers Genius. Excuse me for the bad English, sometimes I use a translator. When I get home, I'll do a video driver.
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Postby eyrope » Wed Jul 24, 2013 10:10 pm

I returned home. Changed the polarity and the picture turned upside down. But the mirror reflection of the past. I found a video driver circuit and PWM - the regulator.
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Postby TelevisionDk » Tue Aug 06, 2013 2:35 am

If your picture is mirrored don't spin the disc the other way around. The disc has to be mounted the other way around on the motor shaft.
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