Mechanical television

[yagosaga]

Hello,

When Paul Nipkow, who invented the Nipkow disk in 1884, saw the first time a working Nipkow disk televisor on the Berlin Funkausstellung in 1928, he went away, grim and very disappointed due to the low video quality. Of course, the camera and amplifying technology of these times did not tap the full potential of the Nipkow disk.

This here is a demonstration which shows how good mechanical television in reality can be:

http://www.youtube.com/watch?v=osF5gg6RKL4

In the times of HDTV, many people think that a television standard of appr. 30 lines per frame and a video bandwidth which can be distributed in telephone bandwidth, might not able to display recognizable video content.

This video demonstration should reject this opinion. As video source was selected a RCA Victor commercial from 1961 for color tv, displaying in black and white on a Nipkow disk based on the standards of 1928 and recorded in 2006. One can see that most of the video content is recognizable - even as it is displayed in 32 line format.

Eckhard

[Sandy G]

The scanning disc system wasn't all THAT shabby-IIRC, the used a variant of it on the moon for the 1st couple of manned landings.

[Eric H]

Would it be possible/practical to build a higher-def mechanical TV, say 500 lines or so?

[yagosaga]

Hello,

Originally Posted by Sandy G

The scanning disc system wasn't all THAT shabby-IIRC, the used a variant of it on the moon for the 1st couple of manned landings.

The tv camera on the moon was a tube-based b/w camera with a color wheel like the CBS color system of the 1950's. This was the most reliable color tv system under space conditions (with appr. 10 frames per second).

Today, DLP Video projectors even use a color wheel, see:

http://www.audioholics.com/techtips/...chnology2.html

Originally Posted by Eric H

Would it be possible/practical to build a higher-def mechanical TV, say 500 lines or so?

The limit was reached with 441 lines in the 1930's. Even in the time when picture tubes and iconoscopes were common, mechanical film scanner with 441 lines were used. Gerhard Bauer has held a lecture about a 441 line mechanical scanner "for people, film and slides" used in German television from 1938 to 1945 on the ETF convention in 2005.

I hope that I sometimes can update my Nipkow disk monitor with color. But the color NBTV standard is still in discussion and PCBs are not available for now.

BTW: Steve McVoy is building a color mirror screw monitor:

http://www.earlytelevision.org/color_mirror_screw.html

It is an awesome project, I check the news webpage of the ETF every day for updates.

This might indicate a slowly growing interest in mechanical television.

Eckhard

[fujifrontier]

i want a nipkov TV

[yagosaga]

Originally Posted by fujifrontier

i want a nipkov TV

You can buy one at MUTR in U.K.:

http://www.mutr.co.uk/prodDetail.aspx?prodID=1420

Or you can built a Nipkow scanning disk televisor by yourself. Here are some links which I find interesting:

http://www.nbtv.wyenet.co.uk/beginners.htm
http://www.televisionexperimenters.com/
http://www.sptv.demon.co.uk/nbtv/
http://www.tvdawn.com/index.htm
http://www.bretl.com/mechtvprogress/mechtvprogress.htm
http://taggart.glg.msu.edu/ich/nbtv%2Ehtm
http://www.eht.com/oldradio/arrl/200...rly-ham-tv.htm
http://www.hawestv.com/mtv_page/mtv_page.htm
http://www.kevinhadfield.co.uk/mechtv01.html
http://www.rolandandcaroline.co.uk/h...anical_tv.html
http://www.copycoder.com/phpbb2/view...1857ef06552e24

Software for converting AVI videos into compatible narrow band tv standard (32 lines):

http://users.tpg.com.au/users/gmillard/nbtv.htm

The generated .WAV files do work with b/w Nipkow disk televisors and with color Nipkow disk televisors.

Did I forget some important web sites regarding mechanical television?

Eckhard

[wajobu]

Pretty fascinating sites, but I like that catchy RCA tune, "Wow!, my color TV..."!

[fujifrontier]

indeed, I do too... silly question, but do the hand-built nipkov TVs have a line-in connection, or how would you connect it? lol @ nipkob burn-in :P

[rld-tv01]

Quote:
Originally Posted by fujifrontier
do the hand-built nipkov TVs have a line-in connection, or how would you connect it?

The Video is narrow band so it is in audio spectrum. You could use rca plug as video line-in of receiver to connect to the audio signal from CD or tape or computer sound card. You could also build a line-in for sync control.

[Sandy G]

I remember the "Wow !! Color TV !" ads...Seems like they used 'em way after '61...I was 4 in '61, doubt if I'd remember that...But they COULD have used 'em til the end of the Roundie era in '65-'66 or so...Seems like they were used on Disney's Wonderful World of Color, which was little more than an hour long commercial for Color TV...RCA's new Color TV...WOW ! <grin> Remember yr dad wearing a porkpie like Mr. Wow had on ? Mine sure did, as he's bald as a billiard ball...hehehehehehe....

[fujifrontier]

Originally Posted by rld-tv01

Quote:
Originally Posted by fujifrontier
do the hand-built nipkov TVs have a line-in connection, or how would you connect it?

The Video is narrow band so it is in audio spectrum. You could use rca plug as video line-in of receiver to connect to the audio signal from CD or tape or computer sound card. You could also build a line-in for sync control.

wait, so I could use a cassette recorder to tape nipkov TV?!!! HAHAHAHA, THAT'S COOL!!!

[yagosaga]

Hello,

I use a simple line-in connection for the Nipkow TV. Recording picture and sound with a cassette tape recorder works well. I can reduce the bandwidth of the video signal down to 8 KHz without notifying any lower picture resolution.

Eckhard

[old_tv_nut]

www.nbtv.org sells a series of club CDs with 30 and 32 line video on one channel and accompanying audio on the other.

[bgadow]

On my last trip to the Radio Historical Society museum (Bowie, MD) they had on display a small, modern mechanical tv. I don't know too much about it but found it fascinating. It ran off of a cheap portable CD player.

[fujifrontier]

oh, that's grand. for some reason I was under the assumption that a UK nipkov wouldn't work in the US, I saw the toy one on that website and was like "hmm but doesnt it use PAL" before i realised that it didn't matter :rofl: LMAO