CYGN-B

[Greg]

Good 352 data from the 1/4" reels with audio sync preserved is being obtained. The HD24 seems to want way more than the 1vp-p line that the tape gives, so gain for the two audio channels is coming from an op amp on the breadboard. The other stuff on the breadboard in the photo is unpowered for this purpose. It is the audio mod rebuild, and the first part of the 352 signal decoder, which turns out not to be needed.

The 352 data extraction software tool now is simpler. The digitization through the data logger at 90K and the first part of the original decoder circuit thing turned out not to be needed. One just gives a wav file of raw weak recorded signal to the algorithm, and out barfs lots of errors with lots of good data.

I didn't see the show, but the set list for Light Years has caught my attention. Celebrate! Light Years, an historically important rock and roll treasure has survived and is under current study. Ron, does the archive have any info on this show?

The visualizer shows there is good entertaining choreography present. For example, the 352 gains offsets and enables scheme is performing all out in the Sly and the Stones number. But the visualizer does not preserve audio sync while rendering its view of the data. Loading stereo audio and the text file of the extracted data into BELA units and producing an audio synced facsimile of the 6B control signals has previously been proven to work.

So in order to be able to see the data with the audio sync, the missing part of the 6B system needs to be built. The part that took images and signals and produced four channels of XY. I'm going to look through the documentation and return with questions. Brian, is the wire wrap circuit you sent packed carefully intended to have something to do with a four channel system? The docs suggest things such as "summing with offsets" and "rotation select" which sounds very relevant.

[laserist]

The VME wire wrap board was the beginning of my attempt to build a Laserium style system. I was building it for the 50th anniversary of the McDonnell Planetarium. Then I tripped and broke my hand. A call to Jon resulted in the loan of a 6b console, two krypton lasers, an encoder, a CS series projector, and a bunch of other stuff. I sent my original working schematics, but I think the multiplier/multiplexer and variable image rotation was complete. I'm not sure if I'd gotten around to fixed rotation...

[ronhip]

Greg,

It appears that there is very little in the archive beyond the audio tracks, which you already have, and some of the printed programs. The only other item I see is the TV commercial for Light Years. Love 1979 TV!



Ron

Good 352 data from the 1/4" reels with audio sync preserved is being obtained. The HD24 seems to want way more than the 1vp-p line that the tape gives, so gain for the two audio channels is coming from an op amp on the breadboard. The other stuff on the breadboard in the photo is unpowered for this purpose. It is the audio mod rebuild, and the first part of the 352 signal decoder, which turns out not to be needed.

The 352 data extraction software tool now is simpler. The digitization through the data logger at 90K and the first part of the original decoder circuit thing turned out not to be needed. One just gives a wav file of raw weak recorded signal to the algorithm, and out barfs lots of errors with lots of good data.

I didn't see the show, but the set list for Light Years has caught my attention. Celebrate! Light Years, an historically important rock and roll treasure has survived and is under current study. Ron, does the archive have any info on this show?

The visualizer shows there is good entertaining choreography present. For example, the 352 gains offsets and enables scheme is performing all out in the Sly and the Stones number. But the visualizer does not preserve audio sync while rendering its view of the data. Loading stereo audio and the text file of the extracted data into BELA units and producing an audio synced facsimile of the 6B control signals has previously been proven to work.

So in order to be able to see the data with the audio sync, the missing part of the 6B system needs to be built. The part that took images and signals and produced four channels of XY. I'm going to look through the documentation and return with questions. Brian, is the wire wrap circuit you sent packed carefully intended to have something to do with a four channel system? The docs suggest things such as "summing with offsets" and "rotation select" which sounds very relevant.

[Greg]

User puts an audio wav file and a 351 text file directly from transfer into bela.

User sets RYGB channel 1 to 4 for this bela and bela outputs accordingly.

User selects render mode: XYRGB out for ILDA, or control signals from 351 data.

User uses cycloid generators and joysticks to punch in punch out record as AB bus sources, and with 351 enables, gains, and offsets imposed on live output for one of four channels per bela.

This is the software I am writing. So the facts I'm wondering about pertain to two sources of offset signals: the joysticks and the DOG card. Were they at times summed and at other times overridden?

By the way, the sin cos full rotation potentiometers, as Brian said, really do just that. I confess I had to see it to believe it. But so if these quadrature generating devices were used in radar, then what would be the reason for the existence of the De Jur potentiometer that outputs quadrature triangles?

Other photo shows samples of what I think are motors and continuous turn potentiometers, also from Brian. I'll go investigate part numbers at some point. I don't recall ever seeing components that looked like these before.

Thanks for the archival work, Ron. I saw somewhere recently a very short segment of Rock Around The Clock that had a blue low frequency CYGN-B circle and red and yellow triangle CYGN-A cycloids that looked like they were under control of the data. I can't find where I saw it though. But even that is something to test the tool and the score against.

And last, a kind of boring request for clarification regarding Dolby. Ron, you said you had one? I have Brian's dbx 150. Is yours something different?

Some of the tapes say dbx 150 and some say dbx 1:3:1. Are two different devices required? Can dbx decoding be applied to an audio files through software after digitization?

[Greg]

These are the photos I meant to attach.

[laserist]

DBX was 1.3 to 1compression. The early boxes were adjustable. I don't think the one I sent was adjustable.

[laserist]

The DOG card RYGB XY signals were summed with the lower cage RYGB XY signals and then to the center lower lever-lite switches to allow lower/sum/upper cage signals to be selected. The center upper lever-lite switches - up killed the joystick signals, center allowed the joystick signals to sum to image signal, and down killed the image signal but left the joystick signals active.

[laserist]

The triangle wave pots still generate an angular position value and it might be simpler to use the linear change in voltage per degree than to interpolate the sine/cosine values.

[Greg]

The XT20 has been successfully attended to by AMI Electronics in Toronto. Graphic shows the five tracks obtained from Laserium 1 on ADAT. There's audio LR and 352 signal. Previously posted docs show alternate uses of the 8 tracks, one which has a Color Mod track. Which might have been interesting to look into, but I don't think I have any tapes that would have that Color Mod track. No mater. The three mystery signals can be seen (and heard) to do do something nominal until the last third or so.

The sought functionality of having live cycloids with audio synchronous 352 imposed according to channel select is getting very close. We all want to see the goods in laser.

I have all the parts for the Danube board, and with this ADAT transfer have now what possibly is the 352 data that was the actual Blue Danube number, from which the whole Danube thing arose in the first place. It might be that the video here:

https://www.youtube.com/watch?v=oFn0Z4WHCnk

is a performance of The Blue Danube using the 352 data recovered. This data will hopefully be a good example of putting the Danube board through its paces.

[Greg]

Here's a video link to audio synced 351 RYGB sizes mapped to LEDs, and the red gain imposed on a live 6B cycloid. It is most unsatisfying that I had to remove Twist And Shout from the audio in order for the video not to be blocked.

Was beam torquer an offset to the colormod signal? Or was it a separate optical device?

Would be impressive were it not for removal of Beatles music:
https://www.youtube.com/watch?v=nn0YX_1AVA8