Televisor kit

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Televisor kit

Postby LuTELLO » Wed May 21, 2008 6:52 pm

Forgive me, but for now at least I want to just get a televisor kit, and hopefully make my own some other day.

So, what's the best kit to get and the best place to order it from the US?
From what I know, this is the only kit out there:

http://www.mutr.co.uk/catalog/product_i ... 3320ee600f
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Postby Dave Moll » Wed May 21, 2008 8:30 pm

Given the price, the MUTR unit is quite a good place to start. I don't know how much they would charge to ship to the US, but it would presumably still represent reasonable value for money.

A number of forum members (including myself) own one of these.
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Postby Viewmaster » Wed May 21, 2008 9:07 pm

Dave Moll wrote:Given the price, the MUTR unit is quite a good place to start. I don't know how much they would charge to ship to the US, but it would presumably still represent reasonable value for money.


The cost of postage to USA and world wide can be found on the MUTR site here....

http://www.mutr.co.uk/catalog/shipping. ... 3320ee600f

Albert....
added...there is a discusion here all about the pros and cons of the MUTR with a link to utube showing one in action.
http://www.vintage-radio.net/forum/show ... hp?t=13264
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Postby LuTELLO » Sun Jun 08, 2008 3:33 pm

Ok, just received it today, and need some help. First off, the pots are AWFUL! You can tell how bad the connection is when you move them. I'm having major sync problems and hopefully when I replace them it will work better.

The diffuser is also very poor. Anyone know the best thing to replace it with?
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Postby DrZarkov » Sun Jun 08, 2008 3:43 pm

The major sync problems are not a problem of the potis, but of the distance of the disc to the sensor. The manual says mount the disc as far as possible from the sensors. That does not work, it should say as close as possible, but not too close.

The diffusor is indeed very bad, any piece of Tupperware™ would be a better diffusor. The idea is not so bad, try pieces from plastic food packages.

The third thing: Why not change the LED to an ultrabright white? It does work perfect.
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Postby LuTELLO » Sun Jun 08, 2008 4:05 pm

I was thinking of replacing the LED as well.
It's hard to get the disc very close to the sensor because it's a little warped.
There definitely seems to be something wrong with the pots to me. For example, the brightness pot makes the picture flicker wildly and sometimes you have to hold the sync pot in place for it to work. I already desoldered them!
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Postby Panrock » Mon Jun 09, 2008 3:27 am

Here's the image that's now missing from the thread that Dave Moll has mentioned.

This shows the results with a better diffuser fitted and white LED.
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Postby Klaas Robers » Mon Jun 09, 2008 4:42 am

Amazing that it has too a mis-sync of one line. It looks as if this sync circuit works with the missing sync, but gives always an offset of one line. I don't know why this happens, but I heard it more.

The Grant Dixon test pattern should gave two grey scale lines at both sides of the central grey field. The photographed picture has 3 at the left and one at the right.

And also the other test pattern is shifted one line to the right. We see one line with the inverterd checkerboard pattern at the left.
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Postby DrZarkov » Mon Jun 09, 2008 6:59 am

I found out that you can correct this effect, when you turn the poti a little bit down after the motor has warmed up a little bit. It is not a cassette-recorder motor, but one of those cheap toy motors from Mabuchi or similar.
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Postby Panrock » Mon Jun 09, 2008 7:03 am

I've just turned it on Klaas and I confirm this is what it does.

I suspect it is because I removed the printed sync pattern disc and must have then replaced it a line or two out in position. I originally did this because the frame phasing was way out on the kit as received..

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Postby chris_vk3aml » Mon Jun 09, 2008 11:18 am

I am impressed by the angular accuracy of their scanning discs, given that the disc is only (from description) around 25 cm diameter, but I'd guess from the slightly fuzzy image definition, and the inter-line streaks that they're using round scanning holes. It could do with some hf video boost for aperture correction...

Your photographs really are the final 'proof of the pudding' Steve! Did it take much of a time exposure, Steve, or is the image relatively bright?

How big is the image? With a disc of 25 cm it must be miniscule, surely?

Nice work!

Chris Long VK3AML.
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Postby DrZarkov » Mon Jun 09, 2008 3:23 pm

With the original LED it is not very bright, with the white LED it is quite o.k., for my televisor. The picture is very small, I use two lenses, the original one, and a "Gameboy" lense from a first generation Gameboy. That makes it quite watchable.
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Postby Panrock » Mon Jun 09, 2008 8:10 pm

chris_vk3aml wrote:I am impressed by the angular accuracy of their scanning discs, given that the disc is only (from description) around 25 cm diameter, but I'd guess from the slightly fuzzy image definition, and the inter-line streaks that they're using round scanning holes. It could do with some hf video boost for aperture correction...


The disc is only 7½ inches (19cm) in diameter. The holes are 'roughly' round. There is clearly a little periodic error in the holes' positioning. I wonder how these discs were made, presumably from a CAD file ?

chris_vk3aml wrote:Your photographs really are the final 'proof of the pudding' Steve! Did it take much of a time exposure, Steve, or is the image relatively bright?


TBH I've forgotten, but I think I must have put my digital camera on 'night' setting and 'macro' (+ no flash of course).

chris_vk3aml wrote:How big is the image? With a disc of 25 cm it must be miniscule, surely?


Holding up a ruler against the standard magnifier gives a picture size of 11mm x 17mm.

My only niggle is the battery box, stuck to the rear. This is forever falling apart.

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Postby gary » Mon Jun 09, 2008 8:39 pm

Panrock wrote:My only niggle is the battery box, stuck to the rear. This is forever falling apart.
Steve


Ha! I can never get mine apart to replace the batteries.

Interestingly, when there is no signal the disk stops turning (of course) and once I thought I had switched it off. I turned my source off (the PC) and noise on the input started the unit without my knowing it. It ran all night before I noticed it, and I have used it since for a few hours and the batteries are still OK, not bad.

Sensible thing to do is to add a plug-pack socket to it though.
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Postby Klaas Robers » Mon Jun 09, 2008 9:20 pm

If I look at the motor, it might be the same motor that we used in our CD and DVD mechanics. These motors are extemely cheap, about 0,30 Euro but the quality is much better than you might expect from a such low priced motor. Millions/year are made of then.
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