Narrow-Bandwidth Television Association

LuTELLO · Laboratory Assistant Joined: 23 Dec 2007 Posts: 33

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_info.php?products_id=1376&osCsid=02d85fc4806f0f5a7b87af3320ee600f

Dave Moll · Evil Genius Joined: 27 Feb 2007 Posts: 145

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.

Viewmaster · Posted: Wed May 21, 2008 8:07 pm Post subject:

LuTELLO · Laboratory Assistant Joined: 23 Dec 2007 Posts: 33

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?

DrZarkov · Posted: Sun Jun 08, 2008 2:43 pm Post subject:

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.

LuTELLO · Laboratory Assistant Joined: 23 Dec 2007 Posts: 33

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!

Panrock · Posted: Mon Jun 09, 2008 2:27 am Post subject:

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.

Klaas Robers · Posted: Mon Jun 09, 2008 3:42 am Post subject:

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.

DrZarkov · Posted: Mon Jun 09, 2008 5:59 am Post subject:

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.

Panrock · Posted: Mon Jun 09, 2008 6:03 am Post subject:

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..

Steve

chris_vk3aml · Guest

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.

DrZarkov · Posted: Mon Jun 09, 2008 2:23 pm Post subject:

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.

Panrock · Posted: Mon Jun 09, 2008 7:10 pm Post subject:

gary · Posted: Mon Jun 09, 2008 7:39 pm Post subject:

Klaas Robers · Posted: Mon Jun 09, 2008 8:20 pm Post subject:

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.