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I think this is probably a good point to call it a night.
mnem
Hi Dwagon, Did you see my posts
https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg4275517/#msg4275517
and
https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg4275556/#msg4275556
Looks like same video scheme as the 892x series a Gondbes 8220 video converter would be my next stop.
Yup, sure did; and followed that rabbit-hole down to that LCD mod. Very tidy! ![ThumbsUp :-+](https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif.pagespeed.ce._JElyJQqdB.gif)
Problem is that the models we have tech ref on... the ones we've been talking about... are all proper non-greyscale monochrome monitors. Also, this family of monitors are all "1000 line" resolution (IIRC, I read that they "use" ~960 lines), so not too sanguine aboot dropping down to 800x600 resolution. ![Confused :-//](https://www.eevblog.com/forum/Smileys/default/confused0024.gif.pagespeed.ce.5xOqKkq0Co.gif)
There's a CDM-7SX191 monitor on eBay right now for $80... I've been meaning to get into one of these Chinesium video scan converters as a diag tool for a while, so that might still happen... but I think that if I were going to fix this scope, I'd prolly bite the bullet and buy that monitor.
This of course is all dependent on how my dispute resolves out.
I wanted to spend a little time tinkering just to see if there were signs of life; I was hoping it might be easy to mod the CDM-7SF191 I have in that 54600A so it thinks it's a CDM-7SX191.
I may instead try remoting into it over the RS-232 instead... in which case I'll soon be hunting down that software you posted and firing up the old WinXP Toughbook. ![Evil >:D](https://www.eevblog.com/forum/Smileys/default/xevil.gif.pagespeed.ic.tdrs7Uj5gu.png)
mnem
![Blah :blah:](https://www.eevblog.com/forum/Smileys/default/blah.gif.pagespeed.ce.iJS9qlFEPg.gif)
More CRT types needed.
54600A Pixel_data and Marker_dots are already 32 levels internally, but only 2nd and 4th of Pixel_data are used externally.
So taking out all five is pretty simple but the situation should also be very clearly visible in the monitor.
Old Intensity reference pot can grant its pins.
54600A Pixel_data goes through U37 74LS194 and then HB goes to U30 74ALS08, FB does the same but first ORing Marker_dots in U31 74F32, so either will do a final FB.
All gates are used so extra chip must be added, no idea when the device is designed but 5 TTL monitor pins feels a bit too much.
nixiefreqq's neck board has 1 FET and 3 BJTs, I'd say that 5 TTL pins are not there.
Since 74S03 is the earlier model my guess is that later monitors became better and external data level reference was not needed anymore.
So comparing two datalines will tell how the situation is.
Testing with an extra *old* computer monitor should also be pretty easy, if one is available.
One gate chip is needed, old display modes were selected by swapping sync polarities.
Using only green as data is also fine.
Functional monitor is not needed if vertical line movement is possible, since its color value is different it should be very visible.
Maybe duplicating buttons of two side by side machines can do settings.
Resolution
255 V x 500 H 54600B
256 V x 500 H 54615B
54620-series
255 vertical by 1000 horizontal points (waveform area)
32 levels of gray scale
Is it really 1000 pixels?
Vertical is the same as before so monitor is probably also pretty same as before.
I tried to find some tube info but everything was too old.
So no real idea of physical resolution of those 7" mono tubes.
But it can be checked, just compare those old and new 546xx horizontal lines, 1000 res has half the pixel length.
If shorter pixel length is there then different CRT must be also present, if that is the key.