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Mechanical SSTV Steps

PostPosted: Fri Mar 25, 2011 11:23 pm
by Harry Dalek
Mechanical sstv experiments ...Stage 1

I don't know how far i will get with it but had the idea to try and trying is learning .

Heres what i have done ...i have a tin sort of the right size for the LED write head this will be placed close to the drum which has been coated with glow paint as the LED or led Luxeon is controled down it should write raster lines to the drum as a fax machine would write to a paper around a drum ..

But in this case i am interested in 8 second slow scan television timing the glow it seems to have the right glow time and it should be adjustable to the brightness of the writing led.

Thinking how it would work in my head and how it turns out i need to do the next step which is go past this mock up and mount the drum as and the write led to the old dvd movement arms and do a light test if i get lines as i should i better start doing some electronics for it .

PostPosted: Sat Mar 26, 2011 2:18 pm
by Harry Dalek
Stage 2

MSSTV idea is a bit closer today i put it all together and did a line test and speed test ...the drum rotates very nice at high speed and i get a line with a High bright white LED i tested...

Problem with the led is not it being bright enough but line thickness so i am going to put a mask over the slot where the laser diode used to be and adjust that hole size so it writes the light to the drum a bit smaller .

I will show the line when i get it thin enough .

PostPosted: Sat Mar 26, 2011 4:18 pm
by Harry Dalek
Stage 3

I ended up not using a mask over the lenes but readjusting the lens closer to the montor and that did the trick !

I now redid the test and the line is nice and thin i also did an up down movement to see if i could get the raster lines needed and it sure works .

And in day light !

Not even using a Luxeon very impressed with the results see video which i will post after this is posted .

I am pretty sure i can get this thing to work now .

PostPosted: Sun Mar 27, 2011 8:05 pm
by Harry Dalek
I did a night test with the monitor boy it is good ..infact too good this means you can use lowwer light levels if its darker which makes the glow paint pretty adjustable .

I have to point out i have made a sstv using a p7 crt about 20 or so years and that i had to view in a dark room .

This i expect to work on full brightness in the day and adjust back light levels at night.

OK i have been thinking about the next step and this will be a part automatic raster contoled by the drum rotation ,one or half rotation drops the led one line.

This should show how many lines i can get in the raster with this line thickness.

PostPosted: Mon Mar 28, 2011 5:36 pm
by AncientBrit
Ground breaking stuff Harry,

Well done.

Graham

PostPosted: Mon Mar 28, 2011 7:11 pm
by dominicbeesley
Just spotted it - what a smart idea!

Dom

PostPosted: Mon Mar 28, 2011 8:57 pm
by Harry Dalek
Hi Graham Dom

Steve was asking if it were possible to do it mechanicaly ....AND NOT CHEATING USEING PAPER !

I was utubing the paint idea and more i saw more i had to try the idea to do a SSTV mechanically if the paint worked like a phosphor and it sure does ..

I am using a white Hight brightness LED not a luxeon yet which might be more usful for day light operation.

I am iching to try more but the next few days its darn work.

Its pretty much a workable system as its been done via paper for fax for 100 years the only differance i would be using a rotating phosphor instead of paper and doing SSTV .

I can get the raster dot smaller as i am using the same dvd lens that the laser used but it means getting very close to the drum .

Not using a laser as the glow paint glows in the green Freq so i would need a green laser ......bit costly for me .

I think i know whats in your minds perhaps with a rotating mirror and some juggling of the light freq used to make the thing glow less but in any case fingers crossed for MSSTV.

Re: Mechanical SSTV Steps

PostPosted: Mon Mar 28, 2011 8:58 pm
by Andrew Davie
This is really interesting. Keep going.

I really really dislike the use of animating GIF images. They're annoying and make it difficult to study any picture carefully. I hate them so much, that I'm putting in a formal request NOT to use these. Lots of pictures... yes. Lots of pictures compiled into a single animating GIF... no.

Thanks
A

PostPosted: Mon Mar 28, 2011 9:44 pm
by DrZarkov
Animating gif is another kind of SSTV, too. :wink:
But back to topic: Great idea, using phosphor paper! I wonder why nobody, not even J.L. Baird (or any radio amateurs in the years before computers became common to receive SSTV), had this idea before. I really would love to connect a fully mechanical SSTV-monitor to my shortwave receiver, to receive SSTV on 40 meters in a more classic way. :D

PostPosted: Mon Mar 28, 2011 10:00 pm
by dominicbeesley
I'm with Andrew on the animations - though I've turned them off in IE (Tools->Internet Options->Advanced->Multimedia->Disable Animations)

As to the paper - how long does the image persist? This idea could translate into all manner of possibilities! How about a mechanical waterfall display for your valved HF rig would be great for me as I struggle to follow morse when there's more than two people audible...

Dom

PostPosted: Mon Mar 28, 2011 10:09 pm
by Andrew Davie
DrZarkov wrote:I wonder why nobody, not even J.L. Baird (or any radio amateurs in the years before computers became common to receive SSTV), had this idea before.



http://www.taswegian.com/NBTV/forum/viewtopic.php?t=22

Re: Mechanical SSTV Steps

PostPosted: Mon Mar 28, 2011 10:36 pm
by Harry Dalek
Andrew Davie wrote:This is really interesting. Keep going.

I really really dislike the use of animating GIF images. They're annoying and make it difficult to study any picture carefully. I hate them so much, that I'm putting in a formal request NOT to use these. Lots of pictures... yes. Lots of pictures compiled into a single animating GIF... no.

Thanks
A


Hi Andrew

OK i will fix that only reason i did it as it was quicker to up load one like that but i can see i might p...people off No worries

I will have time later this week to work on it at the moment its work home look after the kids !

PostPosted: Mon Mar 28, 2011 10:57 pm
by Harry Dalek
dominicbeesley wrote:I'm with Andrew on the animations - though I've turned them off in IE (Tools->Internet Options->Advanced->Multimedia->Disable Animations)

As to the paper - how long does the image persist? This idea could translate into all manner of possibilities! How about a mechanical waterfall display for your valved HF rig would be great for me as I struggle to follow morse when there's more than two people audible...

Dom


Hi dom depends on the light level in the viewing room and the light intencity used sort have to adjust the LED for viewing in normal light room light to full intencity on the led ,,,,,well the one i am using at the moment .

But you can see it if you drop it back in room light .

I have done a night test it and for SSTV 8 sec needed No problem it could do that easy ! infact you could knock the LED Back ...from what i can see you could view any picture for some time till the next wrote over the last.

So i think its again just a matter of adjusting the LED intencity to get it right .

Yes lots of ideas for this stuff ..could make a mechanical scope same parts in mine ...lots of laser mirror ones but not a glow paint one !~

I sort of wonder why no one sort of bothered much with the idea interesting baird had a patent but did he make one ? bet he did ! the bloke had a go every thing perhaps apart from a mirror screw ?

PostPosted: Mon Mar 28, 2011 10:59 pm
by gary
harry dalek wrote:Not using a laser as the glow paint glows in the green Freq so i would need a green laser ......bit costly for me .


I am not necessarily promoting it's use in this instance but I have just ordered one of these green lasers to see what it's like:

http://www.futurlec.com.au/Laser_Diode.jsp

At $13.55 it's not too expensive...

PostPosted: Mon Mar 28, 2011 11:09 pm
by Harry Dalek
DrZarkov wrote:Animating gif is another kind of SSTV, too. :wink:
But back to topic: Great idea, using phosphor paper! I wonder why nobody, not even J.L. Baird (or any radio amateurs in the years before computers became common to receive SSTV), had this idea before. I really would love to connect a fully mechanical SSTV-monitor to my shortwave receiver, to receive SSTV on 40 meters in a more classic way. :D


I'd love others to have a go never know where it leads .

Well the mechanical part is really easy one old Hard drive one old cd or dvd rom ,and gut it for the laser motor and guides and a led and i am using a chicken spice tin perhaps i should call this project chicken television :wink:

I used to short wave listen for sstv as well arr those were the days television ....a picture at a time .