Aurora Multi-Standard Converter

Aurora Standard’s Converter’s

Aurora Low Cost Standard Converter with RF Modulator

The cost of the converters are shown below and represent a fully assembled and tested unit including shipping and insurance to all of North America and Western Europe. (Other areas may be higher. Please enquire before ordering) I am only able to take Paypal payments at this time. Please send a Paypal payment (in US Dollars since Paypal charges me a processing fee) to the account “converter (at) comcast.net” with the following information:

1) model number of unit being ordered (example SCRF405A, etc.)

2) shipping address

3) phone number (required by customs for international packages)

A 9VDC 250ma power supply with a 2.1 X 5.5mm power connector (positive center) will need to be supplied by the user. This does not come with the converter.

The following monochrome versions are currently available:

SCRF441NM: NTSC(525) -> 441/30i with all System M (1946) and (1940) channels

SCRF343M: NTSC(525) -> 343/30i with all System M (1937) and (1934) channels

SCRF343A: NTSC(525) -> 343/30i with all System A channels

SCRF405A: PAL(625) -> 405/25i with all System A channels

SCRF441PE: PAL(625) -> 441/25i with System E channel 1 and Berlin I/II

SCRF455E: PAL(625) -> 455/25i with System E channel 1 and Berlin I/II

SCRF819E: PAL(625) -> 819/25i with all System E* channels

SCRF819F: PAL(625) -> 819/25i with all System F and System E* channels

SCRF819L: PAL(625) -> 819/25i with all System L and System E* channels

ALL MODELS IN STOCK, $290 each or $565 for two

Special full color converters:

SCRF525M-SC: NTSC(525) -> 525/30i sequential color with all System M channels

IN STOCK, $290 each

SCRF405A-NTSC: PAL(625) -> 405/25i NTSC color with all System A channels**

IN STOCK, $340 each

Mechanical Television converter:

SC32/30: NTSC(525)/PAL(625) -> 30/12.5p Baird and 32/12.5p NBTV

OUT OF STOCK, $225 each

*Note: The SCRF819E model has full video bandwidth while the SCRF819F and SCRF819L models

have reduced video bandwidth in System E.

**Note: The SCRF405A-NTSC is designed to output the experiment BBC 405 NTSC composite color signal used during testing in the 1950’s. The chroma channel can be disabled on this unit making it operate exactly the same a standard SCRF405A.

All units have a converter bypass mode which allows them to be used as just an RF modulator. They can also store one frame of video for use when no signal is connected to them. I preprogram them with an appropriate image for the type of converter, such as Test Card C for the SCRF405A, or the RCA “Indian Head” test pattern for the SCRF441NM.

User manual for current revision Low Cost converter detailing construction and usage here:

User Manual for SCRF Models

User Manual for SC Models

I can be reached by email

Frequently Asked Questions:

1) What else do I need?

First you need to supply an AC adapter that converts the mains power in your country to 9VDC at 250ma. The adapter needs to have a standard 2.1 X 5.5mm power connector with the center terminal positive. These are available at most electronics part stores for a nominal cost.

You will also need to provide a cable to connect the inputs and outputs of the converter to your equipment. The inputs are RCA (phono) connectors, and accept standard composite video and line level audio. You connect to any standard audio/video equipment using coaxial RCA cables.

Finally, you will need to provide a cable to connect the RF output “F” connector on the converter to the antenna terminals on your television. This may require an adapter to change over to the connector used on your television, or may require a Balun transformer if your television has a 300 ohm twin lead input. These are also readily available at your local electronics store.

2) What can I use as a source for the converter?

Since the converter accepts standard composite video and line level audio, you can connect the outputs from any consumer or broadcast video equipment. Examples would be DVD’s, DVR/PVR’s, VCR’s, tuners, satellite receivers, video iPod’s, etc. As long as the video is composite NTSC/PAL/SECAM (based on the converter model) the converter will lock to it. Since PC’s are becoming more popular for use as tuners and digital video recorders, the composite output from a properly equipped PC can also be used.

Also, when no video input is detected, the converter will output a user storable image. The unit ships with an appropriate test card for the region (this can be easily overwritten by the user) which is great for setting up the television, servicing the television, or just demonstrating it when no video source is handy.

3) How’s the quality?

In a word, excellent! I have been designing broadcast video equipment for over ten years, and the technology in this converter is borrowed from this experience.

First the converter uses a three line interpolator which takes information from three adjacent lines to create each line in the output. While this can be done with a two line interpolator, the result is a jagged looking picture.

Next, all video processing is done on a field basis. This is extremely important to retain the original temporal (motion) information in the original video. Basically, each frame of video is comprised of two fields of information, each slightly separated in time. By proving field based processing, this temporal information is retained yielding a perfectly smooth image.

I am constantly asked if the converter provides a “deinterlacing” function. As shown above, this should NEVER be done. If the source and output video are interlaced as is the case here, deinterlacing will significantly degrade the image. Because deinterlacing combines the two independent fields into one single frame, the temporal difference between the two fields is lost, so the interlaced output video will now contain only 30 or 25 frames of video per second, not 60 or 50 fields of video per second. This results in jerky motion in the output video. Since this only affects motion, still images will not be as effected. Deinterlacing is a function common to PC’s which use progressive scan monitors, not interlaced monitors. By deinterlacing an image, the PC will show a better still image at the cost of smooth motion.

The converter uses cutting edge electronics design also borrowed from the broadcast industry, like the latest Xilinx FPGA (FieldProgrammableGateArray) for all processing. This allows for field upgrades to add or change functionality.

All video processing in the FPGA is done with 10 bit accuracy and output using a proprietary 10 bit D/A. 10 bits is the only way to virtually eliminate any “contouring” or stair stepping in smooth gradients. 8 bit systems, like those from a consumer video or PC card (even if the card is 24 bit RGB, it still only provides 8 bit’s of monochrome data) will show contouring. The video processing is also done on the raw, uncompressed video. This way there are no compression artifacts as will happen when using off the shelf PC cards which typically use highly compressed MPEG or H.26x compression.

Finally, the RF modulator is a custom design that matches the specifications for the original RF system it is set for. Whether the RF system calls for positive or negative video modulation, AM or FM audio modulation, 6db or 12db carrier ratio, etc, this modulator can do it all with excellent snr and dynamic range.

4) How’s the reliability?

The converter is an extremely efficient design using only 2 watts of power! There is little heat build up, so component reliability is excellent. As of Fall 2006, there have been units in continuous operation 24/7 for over 2 years without a single failure.

OLYMPUS DIGITAL CAMERA

End of section.

Aurora Multi-Standard Converter

Out of Stock!

Front View

The Aurora Multi-Standard Converter is a device used to convert standard NTSC and PAL/SECAM input video to multiple obsolete monochrome video standards. (CBS Field Sequential Color being the only exception with that specific model) It performs the conversions using state of the art electronics and proprietary algorithms I wrote for use in our broadcast products. Some of the key features are:

• Compact, low power, surface mount design

• Fully automatic operation

• Front panel multi-function user push button and Status LED

• Rear panel user switch selectable output standard control

• Internal user switch selectable operating mode control

• Zoom function to display a 4:3 image from a 16:9 source (electronic standards only)

• Extremely stable output: +/- 3% levels, +/- 50ppm timing

• Output clock line locked to input clock for perfect conversions

• 10 bit video D/A for greater than 54db dynamic range

• 32Mb FLASH Image Memory for storing custom images (Multi_Standard Only)

- up to 2 custom images plus one fixed test pattern for each standard

• 300K gate equivalent FieldProgrammableGateArray

• FLASH memory for FPGA firmware

• Extremely accurate algorithms used for conversions:

- Full FIR filtering for image scaling, 3 to 81 tap depending on standard

- Proprietary reverse 3:2 pull-down algorithm for perfect 24fps standards

- All internal calculations done to a minimum 9 bit precision

• Three full frames of static RAM for temporal scaling

• Versatile I/O:

- Composite Video Input (NTSC/PAL/SECAM, 1Vp-p, 75 ohm)

- S-Video Input (NTSC/PAL/SECAM, Y- 1 Vp-p, 75 ohm C- 600mVp-p, 75 ohm)

- Composite Video Output (selectable standard, 1Vp-p, 75 ohm or

2Vp-p 20K depending on standard)

- Stereo Audio Input (16bit, 35kHz, 3Vp-p, 20k)

- Stereo Audio Output (16bit, 35kHz, 3Vp-p, 200 ohm)

- DC power (6Vdc maximum, 500ma)

First a little background. The converter grew out of my personal desire to be able to make some of my own sets display an image, and experience them first hand. While some pre-war 441/30i North American sets can be modified to display current 525/30i video, it can be hard on the horizontal output circuits of magnetically deflected sets due to the poor magnetic materials of the time. Also, earlier North American pre-war sets used completely obsolete standards like 343/30i or 240/24p rendering them unplayable. Some European pre-war sets have it a little easier since they used the 405/25i standard, and some equipment is still available, but becoming scarce, and you are limited to the available programming. Many European immediate post-war sets operated on now obsolete standards like 441/25i and 819/25i that are nearly impossible to find equipment to use with. Also, for those of us who have sets from the other continent, it is very difficult to display images on them without major modifications to the sets given the differences in scan rates. Of course, there was no way to display images on mechanical sets without making a replica camera, and then you are limited to watching what the camera sees.

So besides designing a converter to run my own sets, I wanted to include as many popular (a relative term given the age of these standards :-) obsolete electronic and mechanical standards as feasible. Coincidentally as this idea was being formulated, I read about the restoration of one of the three known CBS Color field sequential sets by Steve McVoy for his museum. We discussed the possibility of a device to convert NTSC to this CBS Color standard, and what the most likely candidates for the other obsolete standards should be. A list was created that contained the most widely used pre-war standards, both mechanical and electronic, North American and European.

The CBS Color version was completed and demonstrated this past April 2004 for the Second Annual Convention at Steve McVoy’s Early Television Museum. Two of the three CBS Color sets were in attendance, (which was amazing in itself!) and were well received by the audience. This was the first time in over 50 years that these sets displayed live images. More information can be found on Steve’s site at: http://www.earlytelevision.org/gray_monitor.html (it is well worth visiting this site if you haven’t for the wealth of information it contains)

The Multi-Standard version was completed about a month later, and further standards were added during this time. It now contains a comprehensive list of standards that can be outputted to various devices. The current list is as follows when in the NTSC mode:

0 - 525/30i interlaced electronic (TimeBaseCorrector, NTSC 1941-Present)

1 - 441/30i interlaced electronic (pre-war U.S. standard, 1937-1941)

2 - 343/30i interlaced electronic (RCA experimental, 1934-1936)

3 - 819/25i interlaced electronic (France, 1949-1983)

4 - 625/25i interlaced electronic (PAL 1950-Present)

5 - 405/25i interlaced electronic (EMI, U.K., 1936-1984)

6 - 240/24p progressive electronic (RCA experimental, 1933-1934)

7 - 120/24p progressive electronic hybrid (RCA experimental, 1931-1932)

8 - 60/20p progressive mechanical (RCA/Jenkins, 1930-1934)

9 - 48/20p progressive mechanical (GE experimental, 1931)

10 - 48/15p progressive mechanical (Jenkins, 1928-1931)

11 - 45/15i triple interlaced mechanical (Western Television/Sanabria, 1929-1932)

12 - 24/15p progressive mechanical (GE experimental, 1928)

13 - 32/12.5p progressive mechanical hybrid (NBTV, 1995-Present)

14 - 30/12.5p progressive mechanical (Baird, U.K, 1928-1932)

15 - 30/12.5p progressive mechanical (TeKaDe, Germany, 1930)

The current list is as follows when in the PAL/SECAM mode:

0 - 525/30i interlaced electronic (NTSC 1941-Present)

1 - 441/30i interlaced electronic (pre-war U.S. standard, 1937-1941)

2 - 819/25i interlaced electronic (France, 1949-1983)

3 - 625/25i interlaced electronic (TimeBaseCorrector PAL 1950-Present)

4 - 441/25i interlaced electronic (Germany/France, 1935-1956)

5 - 405/25i interlaced electronic (EMI, U.K., 1936-1984)

6 - 240/25p progressive electronic hybrid (Baird, U.K., 1936)

7 - 180/25p progressive electronic (TeKaDe, 1934-1939)

8 - 120/25p progressive mechanical (TeKaDe/Fernseh-A.G., 1932)

9 - 96/25p progressive mechanical (Telefunken, 1932)

10 - 90/25p progressive mechanical (TeKaDe, 1932)

11 - 60/25p progressive mechanical (France, 1935)

12 - 50/25p progressive mechanical (Marconi experimental, 1932)

13 - 32/12.5p progressive mechanical hybrid (NBTV, 1995-Present)

14 - 30/12.5p progressive mechanical (Baird, U.K, 1928-1932)

15 - 30/12.5p progressive mechanical (TeKaDe, Germany, 1930)

(Special thanks to Steve McVoy, David Boynes, Peter Yanczer and Roger Dupouy for information on these standards)

To use the converter with any electronic television, a line level (1Vp-p into 75 Ohms) input needs to be added to the set, or an RF modulator for the specific requirements of the set needs to be added. There are no controls to adjust, and the unit will power up in a default image mode, displaying one of user stored images or a test pattern if no video input is present. This makes it nice to display the set with a test pattern from the period, or use during restoration and setup of the set. The only internal adjustment required is to set switch for the desired operation mode NTSC or PAL/SECAM. When a video source is connected to the converter, it will automatically switch to the live mode, and convert the incoming video to the selected standard. All conversions are crystal controlled, and the output waveforms are designed to exactly meet the original specifications for the selected standard including timing, edge rate control, and levels.

Because of the processing overhead in the converter, the video is actually delayed slightly from the input. Because of this (and for support of the mechanical standards that will become obvious below) a two channel audio I/O is included to delay the audio a similar amount as the video so they once again come into sync. In actuality the delay for the electronic standards is minor, and the audio I/O is not definitely required, however there is a noticeable delay for the slower mechanical standards that the audio I/O will compensate for.

For mechanical use, a suitable LED or NEON lamp and driver are required. The output of the converter connects directly to the driver to modulate the lamp. Since there are no sync pulses contained in mechanical video standards (NBTV being the exception), there were two methods for synchronizing the receiver with the transmitter. The first used the same AC Line (Mains) frequency at both ends, and synchronous motors. The second recovered the strong presences of the scan rate frequency in the video, and after amplification, drove a phonic coil (a small synchronous motor) to synchronize the receiver with the transmitter. To make this converter as adaptable as possible, there are two methods of synchronization supported. In the first method, a synchronous sine wave is outputted from one of the audio channels in the converter. For the phonic motor sets (Baird, TaKaDe, etc) the sine wave is attached to an audio amplifier that is connected to the phonic coil and driven as normal. For non-phonic sets, the sine wave is fed to an AC inverter to directly drive the synchronous motor. This later method is a fairly difficult task, so an additional mode was added wherein one of the audio inputs is used to synchronize the converter to the same AC Line (Mains) as the motor is running on. In this mode, a small AC signal from a transformer is presented to the converter derived from the same AC Line (Mains) that the motor is connected to. This method tremendously simplifies synchronization of this style mechanical television.

A complete user manual covering all the above information, and including more detailed discussions and specifications is available for download. The latest firmware, flash cable schematic, flash program, and instructions for flashing are also available.

The above should give a good overview of the design and usage of the Multi-Standard Converter. Since I was asked by several collectors to make this unit available to them, I decided to setup this web page to see what kind of interest there would be for such a device, as the units will need to be machine built. Since it took me over 10 hours for each of the hand built units assembled thus far using specialized tools, it would just not be practical to sell the units unassembled. (0.020”/0.50mm pitch IC’s and 0603 chips for those who are counting!) As I would be doing this in my spare time, I would intend to make one production run using the same manufacturer that assembles our broadcast equipment, and have gotten a quote of $599 USD per unit. This would include the unit and a switching power cube good for 100-240Vac (local plug adapter may need to be provided for some countries). The price does not include shipping or applicable VAT’s or customs.

Please send any interest or suggestions for standards directly to me, and I will compile this information over the next few months. If there is enough interest generated to meet the minimum requirements from the assembler, I’ll notify you as to when the units will be available. Keep in mind that this may take quite a few months before enough interest is generated, and it will then be about 8 weeks for the units to be assembled. I can be reached at my email address.

Thanks,

Darryl

Pictures of the Multi-Standard Converter