Baird System Baird Televisor NBTV NBTVA

Baird Televisor Kit
A proposal for a low priced kit which could be marketed through Radio Shack in the US, or Maplin in the UK, alongside the "Crystal Radio" kits and "200 in 1 Electronics Labs", and aimed at the $50 or 30 price range.
Click Here

New Page Under Construction

Baird
C
olour
Televisor

Click Here

Build a Working Baird Televisor !
Use your computer printer to
Print Out a Nipkow Disk !

Nipkow Disk 32 Lines

NEW

Synchronised Disc

Stereo versions of the WAV picture files with Picture on the Left channel & synchronous12 Hz Squarewave on the Right.

Add Right channel audio to the motor drive voltage to synchronise the motor and get a steady picture!
Click Here

If it all works ( ! ) you will now be watching genuine Baird system TV pictures on your own home made Baird Televisor !



Refinements and Alternatives
This is intended to be the simplest possible demonstration of the Baird Televisor. To make it even simpler you can :

The light from the LED's needs to be diffused evenly over an area about half an inch by half an inch behind the disk :

The holes in the disk should be of the right size.
The hole diameter should be 1/32nd of the width of the picture scan:

Click here for a high resolution picture (2610 x 2610) of the Nipkow Disk.
You'll need to save it to disk & use a graphics program like Paint Shop Pro to print it. Get Paint Shop Pro version 3 from www.jasc.com


NBTV Picture Files in Windows WAV Audio Format :
Right Click and "Save Target As..." to save to Hard Disk

 

tcf1.gif1.Central Strip of Test Card F
 including the centre circle
 
 
 
 
 
 

 
 

tcf2.gif2.Close up of Carol Hersee
in Test Card F
 
 
 
 
 
 

 
 

nbtv1.gif3.The letters N B T V
in a vertical column
 
 
 
 
 
 
 
 



Making the WAV file longer using Windows Sound Recorder:

The WAV file is much more useful if it's made longer by repeating the sequence of frames as follows:
Start Sound Recorder, this will be found in
c:\windows\sndrec32.exe or c:\windows\soundrec.exe
Open the WAV file.
Press ctrl c, then ctrl v.
This copies the wav file, then pastes it to the end of itself, doubling the length.
Do this 5 times, and you have quickly made the file 32 times longer.
Save the file. It will now run for 2 minutes 44 seconds, containing 2048 frames, and be 5 MegaBytes in size.

Alternatively, any WAV file can be made to repeat indefinitely in Windows Media Player.
Start Media Player, this will be found in
c:\windows\mplayer.exe
Open the WAV file.
From the Edit menu, select Options, and tick the "Auto Repeat" check box.



About the Pictures
The pictures were generated as Windows Bitmaps, then converted to WAV files on a PC using "Cool Edit 96" by Syntrillium Software, available from www.syntrillium.com

This was converted to a WAV file at a sampling rate of 32000 samples per second:

The sequencing of data in the Windows Bitmap has been carefully studied to ensure that the Baird pictures are:

This ensures that they are compatible with the specification for the Baird and NBTVA systems where:

The disk above is also made to this standard, and should be rotated ANTICLOCKWISE as viewed from the print side. If someone has the time to try playing these sound files into a proper Baird Televisor, I would of course be interested to know the results! 


Mail to stephen@sptv.demon.co.uk  with any comments or suggestions.


Links to other NBTV Sites
NBTVA Narrow Bandwidth Television Association
http://www.nbtv.org

BATC British Amateur Television Association
http://www.batc.org.uk

MZTV Canadian Museum of Television
http://www.mztv.com



Click below to find out
How to draw the Nipkow Disk with Microsoft Excel