mechanical sstv camera project

[harry dalek]

My project at the moment is a mechanical sstv camera 8 second classic mode .
The project is on the NBTV forum in the off topic section.
The Forum is mainly on Mechanical Television such as John Logie Bairds Nipkow system .http://www.taswegian.com/NBTV/forum/

The above images were scanned by MMSSTV ,i can do a few speeds so the image improves with speed ,this one was at the mid range so 60 lines ,i can do 120 but the image size drops but quality improves .
My mechanical SSTV monitor is in the off topic section as well using a glow paint drum and uv laser bit more to it but if interested just ask .
https://www.youtube.com/watch?v=JEmc...ObW8LA

[EdKozk2]

Harry,
Do I understand this right:
Do you have a laser inside of a scannning drum?
Does the scanning beam scan the back side of a
veiwing screen that is coated with glow paint ?

Same idea as storing an image on the old P7 crt's.
Is the image decay rate a problem ?

Cool project
Ed

[harry dalek]

Originally Posted by EdKozk2

Harry,
Do I understand this right:
Do you have a laser inside of a scannning drum?
Does the scanning beam scan the back side of a
veiwing screen that is coated with glow paint ?

Same idea as storing an image on the old P7 crt's.
Is the image decay rate a problem ?

Cool project
Ed

Well the whole project is on the NBTV forum http://www.taswegian.com/NBTV/forum/...318&hilit=sstv

I am not sure if you can view the pictures and odd video if your not a member but this is the link to my project.
How its done and how i came to getting it to work was a long process the idea was right but i needed to get my head around the correct scanning and how to modulate the laser .
Ok the drum is painted in Glow paint i found the type shown in the last few posts was much better than what i started with as its finer the first type i used was grainy so not great for fine detail.
I used a Uv laser to charge the glow paint the amount of time the paint is charged will glow depends on the intensity of the laser ,think i used a 20mw but all that power is not needed.
Now the glow drums rotation is the vertical line speed stepper motor controlling and the horizontal i used a 6 sided polygon mirror from a broken laser printer stuck on a old floppy drive stepper motor but a 4 sided mirror would do too.
Both the vertical and line speed are manual control so just a pot controlling the stepper motors clock speed .
NO on the decay of the light you can control this with the laser modulation intensity control also by the time the drum rotates around whats left of the last image can be over written with a new image .
The idea was to make a mechanical P7 mechanical monitor copying the P7 CRT results i think infact it can out do it i never tried but i am sure it could do 12 sec at least .
I do plan on making another bit smaller .the screen does not have to be a drum i just went with that idea if you read my posts on the project and see the picture one design was a stationary screen.
I documented by photos and video a fair bit of the project i could just about to a cd or dvd of it any case i have lots ,i tried to put a few videos up but this forum doesn't take them.
Ok the pictures below first is the original drum painted in the first grainy glow paint the little picture of john logie baird its a little grainy close up ,the new glow paint drum its the second picture gives a finer image the last image is the line mirror i used with its stepper motor .

[harry dalek]

Some more pictures

The skull picture is an early test lower line number you can view the 120 line picture at 30 60 or 120 just mirror speed the quality improves with speed of cause.

[harry dalek]

More of the mechanical Glow drum SSTV only one in the world because i invented it ------

The grainy pictures are the original painted glow drum bad camera does not help but i least i have a record of my experiments the light green drum is the newer type .

I forgot to mention the laser is Pulse width modulated ,there is no need for the geared stepper motor i just used junk i had in hand that was from a junked laser printer .

If you want any more information again just ask perhaps there will be 2 in the world if some one copies it .

[EdKozk2]

Harry,
Thanks for the detailed description.
Your pictures of the scanned images are really
very good. They really show how long the latent
image lasts, after the glow paint has been excited.
Eight seconds between the next frame, thats pretty
darn good.
Ed

[harry dalek]

Originally Posted by EdKozk2

Harry,
Thanks for the detailed description.
Your pictures of the scanned images are really
very good. They really show how long the latent
image lasts, after the glow paint has been excited.
Eight seconds between the next frame, thats pretty
darn good.
Ed

Well the image lasts way past 8 seconds not sure how long the longest in time CRT Screen Persistence lasts for ,i only know of P7 type and it can out do it .
40 or 50 years ago it would of been all the go for any slow scan tver ,invented to late but never to late for any one interested .