Arrived today "Televisor"

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Arrived today "Televisor"

Postby AdrianH » Fri Jan 21, 2022 12:49 am

This was something I ordered last year when first looking at NBTV, but was delayed due to the shortage of semiconductors. I must admit the Mindsets kit is not what I expected, it came basically as just an assemble only kit, where as I was expecting to mount up the components and solder them etc. So in a way a pleasant change. It was up and running in less than 30 minutes. The images are not perfect but show the principle OK, They have a wavy top and bottom edge and I almost have two images in the lens which I am assuming is down to the strobe sticker not being in the correct orientation to the holes and also being off set slightly (not centred).
But it is a start to decoding the images.
Televisor1.jpg
Televisor1.jpg (338.35 KiB) Viewed 998 times

Televisor2.jpg
Televisor2.jpg (244.54 KiB) Viewed 998 times


Now I wonder if I dare try and remove and re-attached the paper strobe disk?

Adrian
Not wanting to be always dependent on a computer for images.
https://www.youtube.com/channel/UC1fMu-Lioz_6cNhTlqGAqrg
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Re: Arrived today "Televisor"

Postby acl » Fri Jan 21, 2022 7:52 am

Adrian,

Klaas is the expert on this one. There are several improvements to be made and you should get a better picture than that. I will get Klaas to help.

Regards Chris Lewis G6ACL
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Re: Arrived today "Televisor"

Postby AdrianH » Fri Jan 21, 2022 9:07 am

I have had a bit of a play with it and a bit of a poke! I found that two of the punched holes were actually blocked, or had bits in them so use of a pin helped to clear them. So the lines approx 1/3rd from the left and the one at the right hand side has been improved.

I also took a few measurements of the sync disk and although the outside edge wobbles by approx 2.5mm the inside edge is only 1mm and as the sensor is in the middle I doubt the wobbl would have much of an effect, but really not sure as, I know little on these. what I actually suspect now is the whole plastic disk is 1mm off centre so if the holes were punched acuratly on the disk there will me errors in the hole positions now, but would that give the top and bottom edges as shown.

My digital camera really does not like taking an image of the strobing light so this is the best I can get hand holding at present. It over exposes even though I have reduced the exposure by a few stops.
Televisor3.jpg
Televisor3.jpg (139.99 KiB) Viewed 981 times


If I can get the image straightened I would be very happy. But even as it is I thought it good for the price.

Adrian
Not wanting to be always dependent on a computer for images.
https://www.youtube.com/channel/UC1fMu-Lioz_6cNhTlqGAqrg
AdrianH
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Re: Arrived today "Televisor"

Postby AdrianH » Fri Jan 21, 2022 9:37 am

Moved the disk slightly the cog is a good fit on the disk run out of the disk is now less than 1mm. Shot in B&W.
Televisor4.jpg
Televisor4.jpg (105.41 KiB) Viewed 980 times


Adrian
Not wanting to be always dependent on a computer for images.
https://www.youtube.com/channel/UC1fMu-Lioz_6cNhTlqGAqrg
AdrianH
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Location: Near Blackburn, England.

Re: Arrived today "Televisor"

Postby Harry Dalek » Fri Jan 21, 2022 6:14 pm

Yes wobble is causing that wavy line need a better mount for the disk perhaps a vcr head or as i like old HD all run very true on wobble designed into them .
Now you know how to do it perhaps a home made mark 2 might be a better idea than fixing the kit flaw .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Arrived today "Televisor"

Postby acl » Fri Jan 21, 2022 6:42 pm

acl
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Re: Arrived today "Televisor"

Postby AdrianH » Fri Jan 21, 2022 8:31 pm

Thanks acl for the link, I will have a read through the thread.

Hello Harry, well I will be continuing with my own valved 5fp7 monitor at some point, when family things settle. The kit was a quick and simple thing to put together.

Adrian
Not wanting to be always dependent on a computer for images.
https://www.youtube.com/channel/UC1fMu-Lioz_6cNhTlqGAqrg
AdrianH
"Fester, enough of the light-bulbs!"
 
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Re: Arrived today "Televisor"

Postby Harry Dalek » Sat Jan 22, 2022 7:16 pm

AdrianH wrote:Thanks acl for the link, I will have a read through the thread.

Hello Harry, well I will be continuing with my own valved 5fp7 monitor at some point, when family things settle. The kit was a quick and simple thing to put together.

Adrian


No worries Adrian i just got my valve job to display week or so ago holidays or family events tend to slow these projects down .
The kit is great but knowing what needs to really be improved with them or any mechanical television system it works better without things wobbling at speed or the sinewave result is an old old problem with out taking the disk mounts design into account .
Cost i suppose on these things is a factor .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: Arrived today "Televisor"

Postby Klaas Robers » Fri Jan 28, 2022 2:31 am

Adrian,

the synchronisation circuit tends to lock-in with a one line offset. You can see that in the picture on the block-part of the built in test picture. If it is correct, the block pattern should be visible with no extra line at the right or left side. If you look at your photographs (above) you see one line at the far right, that should be at the far left. At the same time the characters of "CARD" are not centered. You see the C touching the left border, while there are two lines white right of the D. By switching the televisor short off and on, the disc has to synchronise again and you may get a new synchronisation. That can be correct, or even shifted one line to the right, so with the D touching the right edge of the picture. This synchronisation errors are part of the 4046 synchronisation circuit and cannot be avoided.

A shifted synchronisation can cause a wobbly horizontal line. You may check if the disc is off-centre, by slightly touching the outside edge of the running disc. If you feel the disc touching your finger continuously, your disc is centered well.

But also a wobbling disc, when the distance between the "strobo-disc" and the opto sensor is changing during its rotation, can cause speed variations of the disc, because the disc is relatively light, so the motor is relatively strong.

Good luck!
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Re: Arrived today "Televisor"

Postby AdrianH » Sat Jan 29, 2022 10:04 am

Thanks for that. If I get the disk to run true then the wavy lines does go away, Just that the glue keeps pulling it back in at the moment so I will need to remove position and re glue it down.

Also I have tried the off and on bit a few times and can eventually get it to center the image.

Cheers

Adrian
Not wanting to be always dependent on a computer for images.
https://www.youtube.com/channel/UC1fMu-Lioz_6cNhTlqGAqrg
AdrianH
"Fester, enough of the light-bulbs!"
 
Posts: 9
Joined: Sat Dec 04, 2021 12:52 am
Location: Near Blackburn, England.


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