CYGN-B

[Greg]

Are you using anything on the line outputs of your Bela DACs, Greg? After removing the anti-DC coupling capacitors, my signals were 0-3V, with a 1.5 VDC offset. So op amps were required to get rid of the 1.5 VDC offset and to increase signal gain to ILDA levels. Prior to that, I also had problems with flattened, offset images.
I also needed op amps on the RGB outputs to control the signal range and levels to optimize the non-linear nature of laser diodes. Then, I added offsets to the colormod signals to decrease the top end, while increasing the amplitude of the signal, effectively taking away from full intensity, instead of summing onto it, which causes clipping and nasty abuse to the laser diodes.
I'm simulating Laserium's colormod by controlling all 3 RGB waveforms with common variables for gain, frequency, offset, & waveform select... except RG & B are 120 degrees out of phase for colormod and all in phase for chopper. IOW, one set of variables control all.
I remember that you previously mentioned using the OPA188, but never saw your circuit. So, I'm wondering whether you had included those adjustable offset & gain capabilities in your circuit design.
Finally getting around to learning KiCad to convert my T4 synth project and op amp circuits into a single SMD PCB, my 1st. Only took 10 KiCad YT tutorial videos and a week. Nowadays, even dummies like myself can accomplish previously unimaginable goals. Gotta love it!

Definitely scaling and translating voltages all over the place, always pandering to the fucking DACs (just joking, I love DACs) for four beam channels has been a tad wearisome. No, I never ordered any OPA188. The multabela system uses only the quad op amp which appears in the CYGN-B schematic: the TL084ACN. I don't think there is anything special about this device. I have a limited supply of genuine TI devices, and a big heap of what are probably pirate devices with a fake TI logo, but they seem to work the same.

For my purposes, the stupidest simple approach has given me less headache than trying to adapt op amp circuits whose operation I don't really understand. I figure, you use a stage of amplification or a voltage divider, depending on if you need gain or attenuation, and then just sum the output with the output of a trim pot that pulls the whole shebang some certain distance in the direction it needs to go.

Oh yeah, no definitive result on the tank glass. It was awkward to hold it, joystick, look, and beware of scatter all at once. It seemed more of a spinning quarterstaff than the flying drumstick I remember.

[Greg]

One more step for multabela, one small leap back in time. Video shows the Tubes number from Laserock2 pretty much as might have been performed in 1981, setting aside some obvious issues:

There is some unwanted noise, especially noticeable in the red channel. That aside, and the initial scramble to tune the oscillators, and the minimally rehearsed performance set aside also, this is yet the window opening into a mighty catalog of long lost choreography.

Video here:
https://www.youtube.com/watch?v=lLJwKQn9JbY

[ronhip]

Greg,

Seeing this gave me a case of "Laserium Flashback"! What a joy! Thank you for all your efforts. You have managed to do what Lumalaser has yet to do, even though they have all the equipment and electronics (or, to be honest, whatever they got from JR, which I believe was a substantial amount.) I'm not disrespecting Lumalaser here, mind you, and hope to see what they can come up with. I know they've put a LOT of effort into trying to bring back the "original" Laserium shows, and I anxiously await their valiant efforts. It's just what you've accomplished on your own is truly amazing. My Laserium hat is off to you.

Ron

PS. Your video camera losing focus was a nice inexpensive way to simulate the "beam brush"!

One more step for multabela, one small leap back in time. Video shows the Tubes number from Laserock2 pretty much as might have been performed in 1981, setting aside some obvious issues:

There is some unwanted noise, especially noticeable in the red channel. That aside, and the initial scramble to tune the oscillators, and the minimally rehearsed performance set aside also, this is yet the window opening into a mighty catalog of long lost choreography.

Video here:
https://www.youtube.com/watch?v=lLJwKQn9JbY

[lasermaster1977]

One more step for multabela, one small leap back in time. Video shows the Tubes number from Laserock2 pretty much as might have been performed in 1981, setting aside some obvious issues:

There is some unwanted noise, especially noticeable in the red channel. That aside, and the initial scramble to tune the oscillators, and the minimally rehearsed performance set aside also, this is yet the window opening into a mighty catalog of long lost choreography.

All hale Greg! All hale Greg! and a hearty congratulations on the tremendous progress that you have made. ronhip said it best.

[Greg]

Thank you, friends and mentors, for the encouraging words. As anyone knows who searches for information on the present Laserium, this page is pretty much it:

http://laserium.com/who-is-laserium/

Ron, I'm wondering if you have any contact with or non-public information regarding Tim, and what really happened to all the materials he got from JR. It would be a great gap to fill if a 1/4" show tape of Starship would turn up. There is a contact us email address on the Lumalaser website, but, not knowing anything about who this person is, I worry that mentioning Starship out of the blue could inspire the destruction of any remaining copies, should they still exist.

I agree, the usually cursed intrusion of autofocus ruining an otherwise perfectly good shot, actually does come in looking like beam brush when shooting scanned lasers.

Hopefully this new osmium photo will serve better.

I know they've put a LOT of effort into trying to bring back the "original" Laserium shows

[laserist]

"Other one is 6b-BTBX.pdf which is 351 frame generator assembly also called bit box. My file is missing page 5 due to file corruption. Perhaps someone with this file could test theirs and see if they have this file with the missing page."

That page is just a frame map with words 15 & 16 mapped out

[ronhip]

Here are some additional bitbox notes of mine. I do have the complete 6b-BTBX.pdf file, but this forum will not allow PDF attachments. If you want it, I can either email it or provide a link if I put it on a NAS somewhere...

OK. Let's try this:

https://www.myqnapcloud.com/smartsha...5yx974785ceg50

Ron

"Other one is 6b-BTBX.pdf which is 351 frame generator assembly also called bit box. My file is missing page 5 due to file corruption. Perhaps someone with this file could test theirs and see if they have this file with the missing page."

That page is just a frame map with words 15 & 16 mapped out

[Greg]

Wow! That's amazing. That is so incredibly interesting. Thank you again Brian and Ron. When compared with the frame maps found in the documents 6b-352_DATA-FORMAT.pdf and 6b-352_DATA-FORMAT_2.pdf and the dates and names on the documents are considered, some evidence appears for what looks to me like phased out development efforts that may have used words in the data frame. Examples: as Brian pointed out, words 14, 15, and 16 suggest providing control signals to some non 6b planetarium equipment, such as star projector and cove lights. Each different frame map document provides some information not found elsewhere.

Of more immediate importance is that, as soon as all the sources of signal noise have been troubleshot, attention will turn to creating a software implementable statement of how the leverlite switch banks, 352 control words, upper / lower / hybrid card cage, rotations and joysticks thing all works together during a show.

Ron, did you create the bitbox.png document? It doesn't have a date, and obviously wasn't scanned from paper. Was it from your own information in the field? That is an entertaining read because it adds coinages: as well as cycloids and dogloids, bitbox.png references pongloids and crystaloids.

[laserist]

I'm not sure the bytes from 13 to 16 in the 351 frame maps were anything but a documentation fantasy. I never saw anything that implied it was done anywhere. I thought maybe Griffith way back when, but now that I'm older and wiser & have a whole lot more experience with major planetaria I'm 99.99999% sure that nothing ever was done with those signals except maybe with Charlie's projector.

[Greg]

I'm not sure the bytes from 13 to 16 in the 351 frame maps were anything but a documentation fantasy. I never saw anything that implied it was done anywhere. I thought maybe Griffith way back when, but now that I'm older and wiser & have a whole lot more experience with major planetaria I'm 99.99999% sure that nothing ever was done with those signals except maybe with Charlie's projector.

I expect that is exactly correct. However, Charlie's projector sounds like it was an awesome and unique instrument, about which detail is sparse. Spotting activity in the data that may have been related to that device could bring a few bits of the light of knowledge to where there is currently none.