Latest converter project

[dominicbeesley]

Hi Darryl,

Any progress to report?

Also I've been playing around with my own NTSC + NBTV "standard" for getting colour video into a single 20kHz channel. I've got something half working see here and here.

Would it be possible to program something like this up, on the new converter, or even better would it be easy to experiment with the various factors like colour burst and subcarrier frequency by reprogramming the device?

I've no doubt that using the DSP stuff on the converter would be able to produce much cleaner and tidier output than my dodgy half-baked software!

Cheers

Dom

[tubesrule]

Hi Dom,
Very interesting implementing quadrature encoding at such a low bandwidth. You are to be commended.

Your question about a progress report came at a good time. The first ten converters are back from the board assembler and are being final programmed now. I'm cleaning up a couple of test pattern images before flashing them into the units, and I expect to have all the remaining pieces in place over the next few days. I uploaded the final cut of version 1.0 of the user manual to the web site earlier this evening. I'm now up to 36 standards and almost 700 RF channels.

The converter is certainly able to output a signal such as your composite NBTV. Each standard is a table of values stored in the microcontroller and downloaded to the fpga. The microcontroller has an attached EEPROM for saving these values off. Right now, I calculate all the required values for each standard and code them into the microcontroller. I've thought about providing a way to allow users to define their own standards, but that is not available yet, nor do I now if or when it would be available. I say this as there are a couple of issues with providing this functionality.

I was able to add a user interface to allow the user to define their own RF System, but this is very straight forward. A standard definitions table consists of up to about 300 bytes containing mostly timing values, gains, qam encoding values, etc. I'm not sure how to present this in an understandable way, and elaborate on what each value represents, and how it is calculated. Further, for standards that use the RF modulator, IIR filter coefficients need to be calculated which can be rather involved.

Since the software and firmware in the units can be updated, (requires sending it back to me unless someone has access to the required tools) this can be added, along with more standards or other changes. I expect that as people use them, they will come up with lots of good additions to the unit. Then it's just a matter of it's possible, and will it fit.

Darryl

[dominicbeesley]

Thanks for the reply Darryl,

Glad to see you've got some working models back. Is the reprogramming through some kind of ICSP interface?

I can imagine that getting all the parameters together must be quite involved and, as you say, far from user-friendly!

I'm saving my pennies up already....

Dom

[tubesrule]

Hi Dom,
The fpga code is programmed into a standard 4Mb SPI FLASH, so this is probably available to most tinkerers. There is an 8pin 2mm header to connect to the FLASH. The Freescale micro has internal FLASH and is programmed through their proprietary single pin BKGD (Background Debug) scheme. You can pick up a USB to BKGD interface for about $40, but the software can be a bit of a handful to wade through. There is a 6pin 2mm header to connect to the micro. The nice thing with this interface is you can fully debug the micro code, at full speed, through this 1 wire interface.

Darryl

[tubesrule]

I finished verifying all the standards and RF channels, and have finally updated my web page with all the new information.

Circuit boards for the first add-on for the converter are set to arrive tomorrow. It's a neon power supply and driver board that will take the switched 12V out of the converter and step it up to 350V. I have only run my Baird with an LED lamp, so it will be interesting to see it with an actual neon running.

Darryl

[ppppenguin]

I now have my review sample. After a certain amount of fun with Parcelfarce (deliberate typo and they deserve it too) and a severe shock with customs payment (£125). Most of this is 17.5% VAT on the approx £550 cost of the unit. Add a little import duty and £13.50 handling fee and . If somebody needs a couple of these it's worth a trip to the US

I'll try to remember to take it to Harpenden along with a TV9-90. If somebody has a small DVD player they would like to bring I'll add that to the setup.

I'll be testing it and reviewing it in due course. There's no way I can begin to cover all the standards it can do. Obviously I'll look at 405. Maybe Dave Boynes can do 819 and Steve Ostler can try some of the mechanical standards. Trying to remember who can use 405 NTSC.

I may be coming up to Geordie land at the end of the month so if there's anyone en route who's seriously interested we might be able to arrange something. Might even be on the scrounge for a couple of nights accommodation somewhere between York and Durham.

[yagosaga]

Hello,

today I have got the new Aurora Design World Converter. Customs payments were 164.38 EUR. I have tested it tonight with the following tv standards:

625 lines / 25p SECAM CCIR (East Germany, channel 1: the converter works fine at once.

625 lines / 25p SECAM OIRT (Russia and former Sovjet Union, channel 11: the converter works fine at once.

525 lines / 30p NTSC on channel 3: the converter works fine at once.

405 lines UK: I had to re-adjust brightness and vertical hold, after this, the converter works fine.

32 lines / 12.5p NBTV: I had to re-adjust brightness and frame control. After this, the converter works fine. Even the exact frame position was synchronised in the correct phase which was not possible with other NBTV sources, I tried. To watch current television programs life on NBTV is one of the most exciting experiences with the new World Converter. And there is only a very small step to colour NBTV with this converter.

Many thanks to Darryl Hock, who gave us such a powerful item, it is a must for everyone who is dealing with antique television.

Kind regards,
Eckhard