XYZ display recommendations

Hi there!

I searched the forums for any threads about vector monitors, XY displays, oscilloscopes … didn’t find what I was looking for.

What are my best options for vector displays? Until LZX creates a full blown RGB stroke to raster converter, I’ll need something to display the super sexy vector output of Chromagnon.

Cost is not really much of a consideration, I’m willing to pay for what I need, which is…

X and Y inputs
Z input (luma)
Scan rate fast enough to handle 1080i60 video … I assume 70 MHz or higher
Screen refresh rate at least 60 Hz
No graticule, or easily removed/disabled graticule

I would be OK with a digital scope if it met all of these requirements AND had a screen resolution at least equivalent to 1080p (2 megapixels).

Also, what are my options for converting the LZX 1V luma signal to the high voltages expected by an oscilloscope Z input? Will I be forced into a DIY solution? Because I am super rusty at electronics and am not currently competent to build my own. I would rather just use an off the shelf solution, or pay someone to custom build a voltage conversion module.

Thanks!!!

Aaron

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You’re going to have an hard time finding an Xyz display above 5/10mhz. The Tektronix 620 has about 2/2/5mhz Xyz bandwidth and that is considered a good scope for scan processing. There was an option to increase the bandwidth of the 620 but that’s gonna be rare. Check the tek wiki for specs on the 6xx series.

There was a mod wiggler thread that listed some of the popular scopes. Look for that.

The voltage expected at the x/y, and z inputs will vary from model to model, even within the same model number, as options were common to tailor it to a specific use case.

If you find a scope that is capable of 1080i resolution please report back here. But I have my doubts.

Do you Need 1080? May be more realistic to go with something in the 620 ballpark.

This is one of the better captures I’ve done of an SD signal off the tek620:

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@pbalj Wow. Thanks for dropping that capture. So good

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What about something like this?

Tektronix 2235

https://w140.com/tekwiki/wiki/2235

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I don’t think there is a monitor that exists that meets your stated requirements above. Good luck.

Chromagnon will have gain adjustments for the XY & Shape outputs, so it should be plug-and-play.

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Really? It can output +/- 30 V?

What is it about my requirements that’s so exotic? Am I not understanding this? There are plenty of oscilloscopes in the 70 and 100 MHz ranges.

I am familiar with this vector monitor, but I’m still not getting why I can’t just use an oscilloscope with higher bandwidth.

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Finally found that Mod Wiggler thread – it was not found by the site’s own search engine.

https://modwiggler.com/forum/viewtopic.php?f=48&t=29973

I think I’m starting to understand the issues … the high-end oscilloscopes have etched graticules.

And apparently the Z input is often AC coupled? Causing issues with overall variations in brightness when the signal content changes?

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And there are links to an LZX wiki page that no longer exists

http://www.lzxindustries.net/wiki/index.php?title=Oscilloscopes_%26_Vector_monitors

:cry: :cry: :cry:

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try Internet Archive: Wayback Machine
you can find all kinds of neat things on the old LZX site :slight_smile:

this is not an area that I’ve explored or know anything about though so I can’t be any more helpful than that

Doesn’t look like the Wayback Machine actually captured that page.

This is why I hate the Internet sometimes… everything is ephemeral, and it’s all vulnerable. I understand that Lars had to take the Wiki down due to malicious actors hijacking the server. Same thing happened to me once upon a time. :cry: :cry: :cry:

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Update: after weeks of searching I have made some determinations. First, in the last four years or so the price for a Leader LBO-51MA or Textronix 606 / 608 has quadrupled. I attribute this to the mentions in that epic Mod Wiggler thread, and some YouTubes videos showing cool graphics with the 606.

So those are right out. There are a few o-scopes with external graticules out there for semi reasonable prices. The highest bandwidth I have seen for an XYZ scope is 10 MHz. There are also some that appear to have external graticules in the photos, but there is no documentation available to confirm.

Video game vector monitors are being made available again via DIY kits to re-yoke raster CRTs. The idea of XYRGB is very exciting but there won’t be any Rutt-Etra type effects because these displays are way too slow. But still, cool potential for pure oscillographics.

I’m compiling a list of my findings and will publish once I have secured the unobtanium. At this time I can say this much~~~~~~~~~~~>

oscilloscopes known to have internal graticule
BK Precision 1522
BK Precision 1540
BK Precision 1560
Tektronix 454
Tektronix 465
Tektronix TAS series

oscilloscopes that appear to have internal graticule
Tektronix 647, RM647 50 MHz
Tektronix 647A, R647A 100 MHz
Tektronix T932
Tektronix T935A

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UPDATE: I’ve got at least one working scope that seems to do all of the things, but I don’t have a raster processor so I haven’t been able to verify that it can display full monochrome video. But I’m pretty sure it will do a decent SD image, it’s 10 MHz. Intensity modulation accepts a reasonable voltage range, TTL compatible @ 0-5V.

What I’m really excited about is a 30 MHz scope with removable graticule. This is a big step up, should be OK for 720p30. A little bit of upscaling and this might be close enough to what I am trying to achieve. It’s on order, but hasn’t shipped yet.

Once I have at least one working unit and one backup, and a way to verify its ability to scan video, then I can reveal model numbers. But I might opt to do that privately as to avoid bidding wars and overheating the market. I’ve seen Leader LBO-51MAs listed in the range of US$500 - $700.

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I haven’t been able to test it without a Chromagnon, but I think these scopes I have here won’t work. They will handle up to a 30 MHz signal… but the phosphors are slow, so I don’t know how useful they will be for raster scan manipulation. :smiling_face_with_tear:

Do you currently have a video synth system?

If so, you could probably patch the required XYZ to generate an image on the scope - share a pic (or modulargird link) to work it out.

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I don’t have a decoder yet, waiting on TBC2. No way to get video into the modular setup. But if I send video rate oscillators (Syntonie) into the oscilloscope, the image fades away when I get up into the horizontal frequencies. Likewise, at low frequencies I’m seeing long-ish phosphor trails.

You don’t need an input / decoder to patch a video output to XY display… provided you have core modules (do you?) such as sync, ramps and a luma source for Z. Luma source could be whatever you synthesise within the system, even a few oscillators is a good start.
Luma source might need processing, to bring it from 1V up to 5V

'scope on XY mode, H ramp to X, V ramp to Y, luma to Z.
Scale and invert are useful tools for Z.

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this is bonkers Phil.

I have some Syntonie V009 sawtooths… I guess I could use those to just get an image on the screen. Send a component Y signal to sync inputs of the oscillators & oscilloscope Z input. I don’t have a sync stripper, but I guess that won’t really matter. I’ll try it over the long weekend.

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BTW one good thing about these scopes is they are good with either a 1V or 5V Z input. So I can take a signal straight out of basically anywhere in the system. I put it through a Pulp Logic Att-Off for more control.

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