World Converter WC-01 - Aurora Design

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World Converter WC-01 - Aurora Design

Postby lemke » Mon Sep 07, 2020 2:17 pm

I am looking for a single converter - not the world - I ain't rich. I cannot find any place to purchase their products on the web. I just want to convert standard "low def" NTSC to the club's standard 32 lines. Can anyone point me in the correct direction?
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Re: World Converter WC-01 - Aurora Design

Postby Steve Anderson » Mon Sep 07, 2020 4:17 pm

I think you'll be lucky to find anyone willing to part with an Aurora, no matter the price...

On their website they list the converters as 'legacy products'...

https://www.tech-retro.com/aurora-design/legacy.html

The homepage is here...

https://www.tech-retro.com/aurora-design/home.html

One of the problems is converting the US 60Hz field/30Hz frame rate into 12.5Hz NBTV. The Aurora does it by sheer speed and brute force, but it does it well.

You mentioned 'NTSC',are you after colour? Or monochrome? In which case I refer to it as 525-lines.

On my 'TO DO' list is a converter from 625 50/25Hz to NBTV (monochrome) which is far easier, but that's of no use for those in 60/30Hz countries. Though possibly it could be adapted to produce a 15Hz NBTV output. However, don't expect it soon, I've got too many other things on my plate that are work-in-progress...

Steve A.
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Re: World Converter WC-01 - Aurora Design

Postby lemke » Mon Sep 07, 2020 7:31 pm

Thank you, Steve. I am just looking to convert monochrome NTSC.

I have the feeling this is one of those "you snooze, you lose" kind of situations - I put this hobby aside or awhile and I missed out on getting an Aurora.

If I knew more about programming, I could perhaps use a raspberry pi.

I guess I will just see if I get lucky.

Thank you for the links.

John Lemke
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Re: World Converter WC-01 - Aurora Design

Postby smeezekitty » Tue Sep 08, 2020 8:44 am

The bandwidth of NTSC is quite high so you need specialized hardware. The Aurora converters use FPGAs. There are a lot of software options for converting video files to NBTV though so the cheapest and most practical option is probably to buy a USB capture device and then run the video through NBTV software
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Re: World Converter WC-01 - Aurora Design

Postby lemke » Tue Sep 08, 2020 9:33 am

Steve Anderson wrote:
You mentioned 'NTSC',are you after colour? Or monochrome? In which case I refer to it as 525-lines.

On my 'TO DO' list is a converter from 625 50/25Hz to NBTV (monochrome) which is far easier, but that's of no use for those in 60/30Hz countries. Though possibly it could be adapted to produce a 15Hz NBTV output. However, don't expect it soon, I've got too many other things on my plate that are work-in-progress...

Steve A.


You are very knowledgeable to be able to tackle that project. I would be very interested in this. I would be willing to pay some money for a converter. I realize I can convert with my PC, but I would like a stand-alone device that I could use to put into my televisor's cabinet for real-time OTA to NBTV conversion. I lack the skills and knowledge to program such a device.
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Re: World Converter WC-01 - Aurora Design

Postby Steve Anderson » Tue Sep 08, 2020 1:49 pm

smeezekitty wrote:The bandwidth of NTSC is quite high so you need specialized hardware.

To a degree that's true, the hardest part is finding an A-D which is fast enough, easily available and at a sane price. The rest of it is reasonably straightforward.

The closest I've seen that meets those criteria is the AD7822, it can sample at 2MHz (just fast enough) and is eight bit. There is the old CA3306 which can sample at 10+MHz, but is only six bit and almost impossible to find these days, though it 'would do'. There's also the eight bit version, the AD3308, but at ridiculous prices...don't even bother trying to source them!

Similar to the SSTV-625 up-converter but in reverse, it would use two processors, one to write to RAM, the other to read at the slower rate.

PDF for the AD7822 attached, they're around 10 quid in the UK, say US$14.00...I would guess similar to a pint of beer these days in the UK...

Steve A.

It is possible to use two CA3306s in 'tandem' to generate a seven bit output. Also using oversampling and decimation you possibly could get eight bits, but I doubt its worth the effort. Anyway, it would be more complex and costly than using a single AD7822, so why bother?

I must admit I haven't looked within the past few years for a suitable A-D, maybe there are newer devices that I'm unaware of...time for some research...

Later...well, I did have a look around for similar spec'ed parts, few and far between, they're either too fast (56GS/S...what!), too expensive, or in ridiculously small SMD packages, i.e. not hobbyist friendly...so it looks like the AD7822 it has to be...it may be worthwhile stocking up for the future before they are also deemed obsolete...at least those in DIL/DIP packaging...

Farnell/Element14 UK..1079304
RS UK......................709-6777
Digikey US................AD7822BNZ-ND

I did try finding the Australian websites for the above suppliers, but kept getting redirected back to the Thai sites, I guess due to my location...though it doesn't happen when I visit the UK or US websites...even though all three suppliers listed have Thai websites...
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