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My DIY Audio Scope so far (will update)

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doity

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Hi,
a fine project and I´m very interested in the video - but "it is private".
So I can´t see something

Thanks for another try to public the video

Stay healthy
Jörg

OK try it now. I guess I didn’t finish publishing it.
 

Sonik Wiz

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First Picture!! I still have some work to do on the front panel because as I mentioned earlier that when I did the initial measurements I did not take into account the shape of the screen. Therefore I couldn’t line up the lights as I envisioned and there is not enough viewable space as needed.

I will eventually post a new picture and maybe a video when all is said and done. At least I proved that it could be done....whether it was worth the headache or not who knows? 😒

Let me know what everyone thinks. Would love the feedback.


Luke
Really cool I've watched the video more than once. I like the "4" in the middle & I don't think the widescreen display is a problem at all. Did you say this uses 6" LED display? That's pretty big you can see that from across the room. I am also curious what music and decode format did you use for the YT video?

About a hundred years ago I built something similar but smaller. Actually it was part of a quadraphonic input/output control center:
CABINET.jpg


You can see the rectangular display window where the LED meters went. I had to go to a machine shop to get the hole cut out. I don't have the skills or tools to make it look professional. Like in your project the 'tronics is sometimes the easy part, making an enclosure that looks good & suits your purposes is the hard part.

Here's the little LED board that sat inside the tinted window:
LED METER.jpg


Notice that the LED modules on the left side are inverted. They were red/green with green being at the center. The board behind was just the input buffer board with multi-turn trimpots so I could calibrate the level detection precisely. Of course it is very rectangular to fit the window. Doing it today (which you're kinda getting me revved up to do) I would do the layout more as you have done.
 
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doity

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Sonik, I actually just used 2 stereo sources as my Quad receiver was having problems initially working with the thing. It does have a “Rec Out” function and that is working but the first time I tried it out with the lights nothing worked. Will try again.

The meters do have pots that will adjust where 0 dB is so in theory that should shorten the output of the lights but I don’t know if I want to attempt to try to adjust 4 lights simultaneously and hope that they all match. I would need some sort of test tone or something to do it right probably. I will probably just open up a inch or so more space at the bottom, tidy up the front panel to make it look legit and call it good.

I liked the look of your control center. It actually looks like a piece of pro gear or maybe like one of those kit jobs.
 

doity

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Well I have finished the ‘scope’ for now. It looks better but I have a feeling that I still will have to do more work at some time down the road. The unit gets pretty warm and I have a feeling that the stuff that I used for securing the meters is not really meant for high heat. Will call the manufacturer and ask.

The first stuff I tried was but it was gooey and some got underneath before it dried and ruined the view so to speak. I wish I never started this project 😭
 

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doity

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OK I finally got the thing hooked up to my system. For some reason it was not responding to the output so I had to route the audio through two separate boomboxes and then into the scope. This whole thing was difficult and I guess it wasn’t going to let me get off easy even at the end. Well it works and looks good so I am happy.

I have included a YouTube link with audio this time




Luke
 

doity

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You project has indirectly caused me to order a repair manual for my broken heathkit ad1013 scope(also just happened to locate the source for the manual recently) and it just arrived today, I'm just dying to get it working again! I have almost zero experience but I'm going to try (eventually!)

I wanted one of those soooo bad and I actually bought one off f EBay last year supposedly in excelllent condition with optional wood case and manual. It showed up not working and scratched (obviously not the same one), no case and no manual. The guy didn’t even bother to fight the return claim thank god.
 

furui_suterioo

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I also got mine from ebay untested it worked but was dim and out of alignment. One day I heard a click and the CRT went dark, it has been gathering dust for over a year now. I dont even have a multimeter yet to check if the filament is broken and if it is I still have to check out the rest, wouldn't want to risk blowing a replacement CRT. Hoping it's just the power supply but also wonder about potential blue CRT replacement, also wish had the wood case. I actually got a mini vhf TV transmitter just so I could use my handheld TV as an audio scope display from my laptops mic when playing music, it worked great for a few days but now I've sent it back for a replacement, been going crazy for some kind of audio scope display, really liked your project btw reminds me of pioneer qx949.
 

doity

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Well I wish you luck on repairing your scope. If you get over your head maybe you could find a local repair person through Craigslist or maybe a stereo repair place might take it on since you have the service manual. There was a guy on the Internet who repaired Heathkit stuff but he is no longer with us. He seemed like a nice guy from looking at his web page and videos.

Yeah I was so bummed about mine but oh well, what can you do. I liked the Heathkit because it was a great match for my JVC receiver and it seemed pretty versatile. The Kenwood scope is fugly in my opinion and looks more like a piece of test gear. Apologies to Kenwood scope owners, I meant no offense!

The crazy thing is that my home brew scope matches perfectly with the rest of my system. A complete accident for sure but looking at it merged with the other stuff it blends in so well. Good luck and keep us all informed.
 

Sonik Wiz

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One more for the completists. This is a more dynamic recording straight from the Popular Science quadraphonic test Q8.



Congratulations I really like your project. It's good that it fits in to your system aesthetically too. And too bad it was so frustrating for a while. I guess that's why it's always easier to do the same project a 2nd time.

Strange that it runs so warm. And strange you need to use 2 boom boxes to drive. Is the input meant to be used as a speaker only connection?
 

furui_suterioo

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I heard about the heathkit guy, think theres a yt video of the last one he restored before it was sold, I almost bought the kenwood scope instead of the heathkit but I wanted quadraphonic input, although the kenwood would probably still be working :)
 

doity

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Sonik, the meters are supposed to be used with a CD out or tape out from a receiver. Any kind of line out will do I suppose. Anyway my JVC has a “rec out” function that will send the audio to other components but the lights didn’t work at all when hooked up. I checked over and over. So I had to route the tape out from the receiver to the inputs of two stereo boomboxes and then used their line outs to go to the scope. It doesn’t effect the speaker output but it is a lot of extra electronics that need to be in the chain just to use it.
 

doity

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I heard about the heathkit guy, think theres a yt video of the last one he restored before it was sold, I almost bought the kenwood scope instead of the heathkit but I wanted quadraphonic input, although the kenwood would probably still be working :)
Isn’t the Kenwood a Quad scope? For some reason I thought it was.
 

Sonik Wiz

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Sonik, the meters are supposed to be used with a CD out or tape out from a receiver. Any kind of line out will do I suppose. Anyway my JVC has a “rec out” function that will send the audio to other components but the lights didn’t work at all when hooked up. I checked over and over. So I had to route the tape out from the receiver to the inputs of two stereo boomboxes and then used their line outs to go to the scope. It doesn’t effect the speaker output but it is a lot of extra electronics that need to be in the chain just to use it.
It just occurred to me that if you mounted the LED meters in proper quad configuration inside, say, a 5" funnel you would get a sense of depth to the display, pseudo 3-D.Black funnel of course and dark tinted front panel. And I think the LED units you used would not permit them being back mounted to a surface. But there's dozens of these LED VU meters out there & I bet one would work.
 

doity

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It just occurred to me that if you mounted the LED meters in proper quad configuration inside, say, a 5" funnel you would get a sense of depth to the display, pseudo 3-D.Black funnel of course and dark tinted front panel. And I think the LED units you used would not permit them being back mounted to a surface. But there's dozens of these LED VU meters out there & I bet one would work.
Sonik, you are right that there is probably a way to give some depth to the display and I thought of doing something but drew a blank. I was just lucky they worked at all 🙂

Maybe someone could give it a shot......I know that people are interested in doing so judging from the replies and from some messages that I have received. Thinking back I should had gutted one of those ‘disco light boxes’ that were big in the 70’s and used that as a starting point. Too big maybe though?

You are right that there are a lot of meters available that could be mounted to the back of a enclosure but most of the ones that I have seen are sound activated and would not be a true diagnostic tool.

I hope that others jump in and see what they can come up with. Like I said in a previous post I am surprised that the thing meshes so good with my other components. I snapped a picture with it off to show.


Luke

CB5C8417-2DC8-451D-ADAB-6B031E91A488.jpeg
 

doity

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It just occurred to me that if you mounted the LED meters in proper quad configuration inside, say, a 5" funnel you would get a sense of depth to the display, pseudo 3-D.Black funnel of course and dark tinted front panel. And I think the LED units you used would not permit them being back mounted to a surface. But there's dozens of these LED VU meters out there & I bet one would work.
I thought of more possibilities regarding a fake scope that would add some pizzazz. You could mount a single small LED light in each corner that would fade in and out depending on audio level. Or if someone wanted a scope for 5.1 Surround they could mount a ‘magic tuning eye’ in dead center to indicate the center channel. Wish I would had thought of the LED thing sooner. Oh well. The possibilities are endless!
 
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