Rebuilding my old analog console

[lasermaster1977]

Awesome everyone.

Lasermaster1977: thanks for the feedback and the laser media scan amp circuit. That will probably be my next build. And thanks for checking on the mirror mounts.

On the laser media amp, the LM343 op amp was a high voltage (up to + and - 35v) powered IC. It doesn't look like they are available anymore. I've looked to see if there are any newer equivalents but haven't found any yet. The other op amps TL074 or TL084 run off the 7815 and 7915 regulators. The TIP 40s you have can substitute for the MJ900/1000 most likely.

[Kevint]

Mixedgas: that one still has all the parts. I like the idea about the AO. That might have to be a future project to try.

Found 1 more mirror mount, but I have exhausted all my hiding places.

[lasermaster1977]

Mixedgas: that one still has all the parts. I like the idea about the AO. That might have to be a future project to try.

Found 1 more mirror mount, but I have exhausted all my hiding places.

I've reached out to my machinist friend with diagrammatic details of the 10A mount. I'll let you know if he has time to make some and their cost.

[mixedgas]

Conservatively, How many more do you need? What I might have are very mixed.

Might be easier to have all 10As....

Steve

[Kevint]

Lasermaster1977: thank you for reaching out to your machinist.

Mixedgas: 3 mirror mounts.

[Kevint]

Status: 4 oscillators working well, Summing amps working well, current scan amp works well. Currently building a temporary control panel to hold and the pots and switch so I can actually use the controls effectively. Right now they are just laying all over the place.

The system can produce complex spirals/lissajous, and cycloids. I'm ready to take another step.

I have been watching a number of Laserium videos on youtube. I would like to discuss how certain images are produced and see if it is possible to incorporate them into my system. Let's start with A Million Miles Away. The effect start at time stamp 0.23. A multipoint star starts at amplitude 0 and then ramps to a particular size and then disappears, and the process repeats. (this is just me thinking out loud, I could be totally out of my mind but this help me think things through) - I can see how part of this would partially work manually. You set the xy gain down to 0 and rotate the pot and the image grows in size. Some type of blanking or shutter would have to kick-in to turn the image off and the process repeats. To mimic the pot rotation, could a VCA be used. The X signal is the input into one VCA and the Y signal is the input into a Second VCA. An envelop generator signal in the form of a sawtooth wave feeds the VCA's creating the ramp and I'm guessing the image would start from a point and grow to the size based on the amplitude of the sawtooth wave signal. The sawtooth would have to be pulsed somehow or else the effect would just keep repeating or a switch that selects pulsed or continuous. The frequency of the sawtooth would have to be varied to change the ramp rates, and the amplitude varied to change the size of the image. Still not sure how to turn the image off after the ramp or hold the image at the end of the ramp.

I'm sure the Laserium folks know how this is done. Does anyone have any insight on how to reproduce this effect?

[Kevint]

Here is a link to the video. I tried to clip the section of interest but was unsuccessful.

https://youtu.be/NLWL1YQ8DNo?si=2Nn3IcSK6mYaQjy2

[mixedgas]

I can come up with 2 mounts and a three channel amp in a 1U rack. Same amp you have. I also have a xyI head with Laserium amps, wired with PSU in a metal box.. PM me.

Steve

[laserist]

Laserium had a board the MPMX or Multiplexer Multiplier card:

MPMX.png

Two by two pairs of DP4T analog switches feeding two by two pairs of analog multipliers to select the various inputs to each of the two image busses in the hybrid card cage. The analog multipliers allowed for X & Y master individual gains. The gains for the A&B bus X axis were tied together, as were the Y Axes.

At the Output end the MULT or Multiplier card:

mult.png

the four pairs of analog multipliers controlled gain for the red, yel, grn, blu scan pairs. Note: even though they have separate x & y gain inputs - the inputs for each color were tied together. You couldn't adjust x & y gain independently here. In the beginning Laserium was really good at NOT exposing every variation on an effect you could get another way.

Both the Master X & Y gain, and the individual RYGB gains were controlled via the 351 data track. The laserist had master gains and individual gains both up and down stream. They were used very little, but to occasionally great effect. There was a design approach to Laserium's hardware and choreography that allowed the laserist to have a huge contribution to the performance. For good or bad depending on the laserist...

[Kevint]

OK Laserist, you just made my head spin. Let me read this a few dozen times to see if I can understand what is going on. Thank you so much for the information and taking the time to share your knowledge and insights. I'll respond shortly with a few dozen questions.