My DIY Audio Scope so far (will update)

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That is impressive! I can't quite tell from the pic but are you dealing with SMD stuff also? So tightly packed & so professional looking. May I ask what circuit /layout CAD you used?
i don't use SMDs but i use 16x 1N4148 diodes that are quite small and 1/8 watt resistors some in very small packages.
A lot of work was done to pack everything around the controls potentiometers and switches.
That's why i choose a dual op-amp in a SIP8 package, the NJM4580 to be able to fit them in between.
Here's a picture of a pcb prior installing the ICs and controls.
SIP8 (single-in-Line package 8pins) one row of pins, 8pins.

the SW1 Mono/Stereo sw is in reality Quad/X-Stereo sw... a typo i made...
 

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i don't use SMDs but i use 16x 1N4148 diodes that are quite small and 1/8 watt resistors some in very small packages.

1/8-watt resistors? :oops:

My first job in the business was assembling and soldering components on circuit boards that were about the same size as most smartphones these days. I was the envy of the shop because I could read the color codes on HALF-watt resistors. 🤓
 
1/8-watt resistors? :oops:

My first job in the business was assembling and soldering components on circuit boards that were about the same size as most smartphones these days. I was the envy of the shop because I could read the color codes on HALF-watt resistors. 🤓
You had very good eyes!
The whole unit consume about 150ma max (all leds on), it's a very low power unit.
In reality at any given time there is only a maximum of 16 leds on. They switch on and off so fast as they may appear all on at the same time.
Don't worry, i use a strong magnifier to read the barcodes and i often use the ohmmeter as the brown, red and orange look much alike on these blue resistors.
 
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Production update!
All 9 remaining control amplifiers are completed. Still have 5 display to do and of course the cabinets. You can see the extensive modifications done on each pcbs.
I used many different heatsink, i had 2 double heatsink i wanted to use so i bought individual for the rest. Note: the 7908 voltage regulator need minimal heatsink as only about 10ma pass thru it. All screws are tighten and varnished to prevent loosening.
In the mean time i will do some quality control and testing of every unit to make sure all is working whiting parameters. The pass-thru RCA connectors will be added when i receive the cabinets.
 

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Hmm, it'd have to be three dimensional, or better yet, spherical to show the height speakers...

Got it! Just wire light bulbs to your speaker terminals and you'd have a full scale Atmos audio scope and blinking disco room Kidding... 😋 !
This is what I would like to have as a display on a large TV
I made a video but it did not work
Maybe my grand daughter will help
 

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Rusty, is this something that you put together using an oscilloscope? Unless I missed an earlier comment in the thread I didn’t read how you accomplished this. Anyway, it is great how this thread has morphed from my basic and mostly unplanned experiment into all of these great ideas and projects that are surfacing. May this thread never die!
 
Thanks to Gary (Homer J) I have no idea how this happened

Ron contacted me about getting this video he made of his 70s quad vectorscope. I just uploaded onto YouTube.

Ron can provide the details. I was impressed when he demoed it to me when I visited his Quad Man Cave a couple years ago. I’d never heard of a vectorscope then, let alone a Quad Vectorscope!
 
Rusty, is this something that you put together using an oscilloscope? Unless I missed an earlier comment in the thread I didn’t read how you accomplished this. Anyway, it is great how this thread has morphed from my basic and mostly unplanned experiment into all of these great ideas and projects that are surfacing. May this thread never die!
You made the world a better place for quad users. Without your thread, i might have never built prototypes.
 
Thanks to Gary (Homer J) I have no idea how this happened
It is Santana SACD

A crt vectorscope is the original best way to go!
Unfortunately the way an oscilloscope crt is driven is quite different than that of a tv crt which make it very hard to get similar results on a regular tv without extensive modifications or using computer software (which introduce lag). Unlike a tv crt, an oscilloscope crt doesn't get burned easily when the electron beam is not moving also the meaning of the phosphor screen is longer allowing the display of nice traces. On a tv the meaning is very short and if the horizontal or vertical scan stop, it will quickly make a permanent mark.
But one never knows! Maybe someone will come with a way to solve this.
 
Hello,
great thing - what is the name, type of the scope??
Thanks for more infos
I have a oscilloscope with a kit that shows the X scope I have put the plans
on the bottom they have been on the QQ site before Then I have put
a Security camera in front of the scope then a RCA lead into the back of the RCA input
on the TV not all that clever but it gives me something to look at
 

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I have a oscilloscope with a kit that shows the X scope I have put the plans
on the bottom they have been on the QQ site before Then I have put
a Security camera in front of the scope then a RCA lead into the back of the RCA input
on the TV not all that clever but it gives me something to look at

Hi Ron,
thanks a lot!
 
The technical details are beyond me but could this not be all be done in software? Would a dedicated NUC and an old LCD monitor be another way to do this? As an old color organ enthusiast, I would love to see a display that would optionally incorporate 3?-4?-5? frequency bands with different colors for each band. If processing time is a factor, why not stream from the PC and compensate for the delay there?

As I said, I don't really understand either the hardware or software technical details, so I'm more than willing to hear if this is even possible.
 
The technical details are beyond me but could this not be all be done in software? Would a dedicated NUC and an old LCD monitor be another way to do this? As an old color organ enthusiast, I would love to see a display that would optionally incorporate 3?-4?-5? frequency bands with different colors for each band. If processing time is a factor, why not stream from the PC and compensate for the delay there?

As I said, I don't really understand either the hardware or software technical details, so I'm more than willing to hear if this is even possible.

All you need is a (relatively) inexpensive USB oscilloscope with X/Y inputs, and a analog rotational matrix up front like this one. It has been done before by someone on the forum, and mentioned even in this thread. The problem is that this set up is too "quick", there is no CRT phosphor decay time that makes it easy to look at & interpret. The Wurlyscope includes carefully calculated decay on the led's.
 
Ever since an old friend emulated my 2 MHz Sol-20 8080 cpu microcomputer (https://www.sol20.org) I've thought that much hardware can be emulated in software. I don't understand why someone with a lot more programming chops than I ever had, can't emulate that analogue rotational matrix you referenced, add optional FFT-based color organ routines, and add the display decay delay and output it to an LCD monitor. Stereo Lab can not only decode SQ and QS in software but CD-4 also (though their software is only for Macs). Maybe what I'm suggesting is a super-difficult task to do in software, but that shouldn't stop someone from trying. Even if Wurly1 offered a kit, my shaky arthritic hands and eyesight would prevent me from building it. But I can download a program and make a few cable connections.
 
Maybe what I'm suggesting is a super-difficult task to do in software, but that shouldn't stop someone from trying.
To emulate the long phosphor decay of an oscilloscope CRT on a short persistence raster scan display, all you have to do is create a ‘sliding window’ display memory several field planes deep. Each new field causes the previous field to be rewritten to a lower plane at reduced brightness. This in turn pushes the previous but one plane lower down and reducing its brightness again etc., etc. The sum of all planes is used as the instantaneous video signal for each pixel. You might need a dozen planes to make it look realistic. Easy!
 
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