Compact Fire Drum
Posted: Tue Sep 26, 2017 5:18 pm
So my first mechanical TV is built and I am still refining it but I have the urge to start a new design. Here is what I am thinking...
Make a drum that has either 32 or 60 leds on it. For simplicity I will describe the 32 line version. I would put 32 led's on a drum. To make it compact I would only have 8 segments, so a line of 4 led's every 45 degrees. The first line would have led's for line 1, 9, 17, 25. I would use some kind of mechanical divide by 4 to give one sync pulse per 4 revolutions of the drum. Only one set of led's would be driven at anytime. No adjacent led's would be driven at anytime of course. To do a 32 line with 4 revolutions per frame would require a speed of 750rpm x 4 = 3000rpm for a 12.5hz picture.
The signal would be done a bit like Harry's inductionvisor but multiplexed into 4 sets of led's to make the compact design. Each vertical frame would cover a full 45 degrees of the drum so the image could be quite large as compared to the drum size.
The big one is, can I manage a 3000 rpm drum say around 200mm diameter? Is this idea flawed? Are multiple light sources cheating the spirit of mechanical TV? Any ideas or comments?
Other things I would like to add to this would be:
Colour. can you have sound with colour, 3 channels?
I wonder if an Arduino can handle the bandwidth of colour and sound or 60 lines or both?
These are is my thoughts for now and I am not locked into anything. I will have some good resources over Christmas to put some energy into another mechanical TV. I have a second PCB from Andrew and would like to use this, as it is a great shortcut to completing a design. One thing is for sure I want to build another machine.
Cheers
Keith
Make a drum that has either 32 or 60 leds on it. For simplicity I will describe the 32 line version. I would put 32 led's on a drum. To make it compact I would only have 8 segments, so a line of 4 led's every 45 degrees. The first line would have led's for line 1, 9, 17, 25. I would use some kind of mechanical divide by 4 to give one sync pulse per 4 revolutions of the drum. Only one set of led's would be driven at anytime. No adjacent led's would be driven at anytime of course. To do a 32 line with 4 revolutions per frame would require a speed of 750rpm x 4 = 3000rpm for a 12.5hz picture.
The signal would be done a bit like Harry's inductionvisor but multiplexed into 4 sets of led's to make the compact design. Each vertical frame would cover a full 45 degrees of the drum so the image could be quite large as compared to the drum size.
The big one is, can I manage a 3000 rpm drum say around 200mm diameter? Is this idea flawed? Are multiple light sources cheating the spirit of mechanical TV? Any ideas or comments?
Other things I would like to add to this would be:
Colour. can you have sound with colour, 3 channels?
I wonder if an Arduino can handle the bandwidth of colour and sound or 60 lines or both?
These are is my thoughts for now and I am not locked into anything. I will have some good resources over Christmas to put some energy into another mechanical TV. I have a second PCB from Andrew and would like to use this, as it is a great shortcut to completing a design. One thing is for sure I want to build another machine.
Cheers
Keith