Seconding Patreon, I’d definitely be able to contribute a couple dollars a month.
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I didn’t have any oscillators handy so I’m using the audio from Toejam and Earl, but it works. X and Y can be independently switched between internal and external. The phone camera doesn’t really show it, but the composite input changes the color of the beam.
TO DO:
-add level controls for X, Y and X+Y inputs
-move all picture controls, composite input and power switch from main board to a panel
-bypass any controls I don’t need
-clean up the wiring
-make an enclosure
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Picked up a carload of old Sony and etc. broadcast gear today… going to take a year or several to learn how to use this stuff, but super pumped.
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I just pulled out my scope that got broken in my last move and turns out it wasn’t broken after all, the cap on the XY button had come loose (a different loose button cap was why it ended up in the trash and then my apartment to begin with, so no surprise another one went - most of them are on the ends of 6"-10" steel wires that physically push the actual switches at the opposite end of the main board, so eventually they develop stress fractures and that makes them come loose and you have to glue them back on) so when I thought it was in XY mode it wasn’t actually switching. So that’s fixed, and while I was in the service manual looking for information on the Z modulation option that isn’t installed I found this:
Checked, it’s right there easily accessible on the CRY board, and since I don’t need the Y output I can disconnect that and use its plug as a Z input.
BUT
there’s absolutely no indication of the voltage range it needs, and I only have two channels of DC coupled audio output (from my Axoloti) so it’s a bit of a pain to just connect a signal and see what happens - I assume line level audio should be pretty safe though.
Anyone know their way around scopes and have any insight into this? I don’t want to burn it up.
Anyway, if it works I’ll pick up the cheapest 4 channel DC coupled USB interface I can find that’s known to give OK results, but in the mean time I’m just happy to have this scope working and be able to start using the Axoloti and a MIDI controller as a standalone XY vector synth without having to buy anything at all (other than a couple BNC connectors so I can make a 1/4" TRS to 2xBNC splitter cable instead of using an insert cable with 1/4" → RCA → BNC adapters stacked on it).
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Anyway this means I can stop screwing around with that old Radio Shack CRT for XY stuff and dedicate it to rescanning and eventually building a tiny Wobbulator.
Grey wire off, white wire on and if the service manual isn’t lying I now have a Z input.
For the record, this is a Hameg HM205-2 scope, so if you have a chance at one grab it because on top of being a pretty good scope it apparently has a secret Z input.
EDIT: it’s TTL only, unfortunately. There’s an analog modulation input marked on the schematic but it shows two caps in line and a resistor to ground but doesn’t provide values (and they took it off the schematics for the next version of the scope entirely, so it’s probably high risk - it’s wired straight to a CRT pin and seems like the sort of thing that probably sent a lot of scopes in for service when people tried to install it themselves and then fed too hot a signal in or something). But and least now I can do simple blanking, and it still works fine as an X-Y display. No scan processing though.
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trying to get gud with the edirol CG8 mainly 
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You should share some of what you’ve done so far! That machine is super interesting.
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Stayed up late last night and tracked down the relevant component values in the German service manual of the previous generation of my scope, so in a week or two when I pick up the caps (and a higher voltage resistor than what I have handy, just to be on the safe side) I’ll either have a much better scope or no scope at all (and probably/hopefully won’t electrocute myself working directly on the neck board of a CRT, - discharged or not those things make me nervous).
The schematic for my model had the Z-mod hookup drawn but not labeled and the next version took it out completely so I got the feeling they were making it progressively harder for owners to try installing it themselves and end up needing their scope repaired. I guess I was right, because the previous version had it fully marked on the schematic but not mentioned anywhere in the text. The Z board on that version is basically identical with a different layout, and the actual Z-mod is completely identical so it should work, and hopefully I’ll be able to finally do full blown, analog scan processing without having to spend more than a couple dollars for the three components and shipping. Looks like it can be done in place easily enough, so I probably wont even have to take the Z board out or anything.
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Combined two videos from 1937. The blaze at the landing of the LZ 129 at Lakehurst and a flight over New York City. The New York City video includes a text panel, “All is serene —”. A euphoric statement made before the disaster in which 39 people died.
It’s hard to see how close easiness and death are to each other.
Sound is mixed from the original Herb Morrison reporting.
https://videos.scanlines.xyz/videos/watch/002b82e4-1827-4822-b921-5d4673dd10ec
Sources:
1937 Pathgrams (Video), WLS Radio (Sound)
Hindenburg Over New York City
1937 Public Domain
Herb Morrison
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Just hastily rebuilt a power supply for testing. I have a late 80s HP bench supply I used for a long time, but the voltage started sagging and getting unstable. This is a pretty standard 12VAC → +/-12VDC board, and then I built a 5V regulator on strip board that I can disconnect if I want. I should have left more space to mount the 5VDC regulator, but thinking ahead is not my jam.
The power supply board is from AI Synthesis, I’ve built like four of these. The little bus board is from: Compact 16-Pin Eurorack Power Bus Board | Electronic things… and stuff, I think I bought it on reverb prebuilt
Aside from the screw terminals on the front, Moffenzeef Modular makes these nice breakout boards for prototyping, i’ll probably attach that to the prototype side of things if I have a longer running project.
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After watching to many scanimate and “mind’s eye” videos, i got obsessed with the idea to do “early computer” animation style video with the capabilities of the lzx memory palace ( mempal).
This are the first sketches for a music video i’m working on. Some easy flight sequences.
Background is a videoloop made in blender (done by a friend) and feed into the mempal via rgb inputs.
The bird / dragon is a 64 frame sequence, played by the mempal media loader. Its animated / modulated with a syntonie quad lfo (x, y, zoom) and another lfo for the Rotation.
Also mixing / keying a little bit the background with the fox shutter and vs rgb matrix.
When i’m ready i problably will rescan it from a crt… we will see.
Maybe its kind absurd to do the animations with analog gear (would be so easy to do everything in blender), but having so much fun working on this. Was happy like a child, when i figured out how to scrubb through the pngs with a lfo 
Also wanna keep the innocent vibe, like you got in early computer graphic Animation films
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After the Scanlines stream I decided to go back into my container of betamax tapes and see what other oddities I have in there. This is some gymnastics recordings running through a dirty mixer (w/ Edirol V4 feedback), then through the MemPal and then back into the Edirol V4 where I used one of the wipe effects for the pillars. The audio track was used as voltage control in the MemPal.
It’s just a rough one-take recording, nothing serious or thought out.
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Added the Z mod to the scope, and I didn’t break it but I’m also pretty sure it needs a much higher voltage than the 10v p-p my tone generator puts out, because it hardly does anything. Enough to tell it’s doing SOMEthing but not enough to tell if would actually be useful. I guess the next step is to try running a signal through one of the spare cheap chip amps I have and slowly bringing up the gain to see if it does anything useful.
When those Watchman CRT assemblies show up I’m thinking that if the brightness control has enough of a range to dim the screen completely, maybe I can hack in Z modulation on that with a simple JFET circuit to modulate the brightness instead of (or in series with) a pot for normal brightness control. Even though it would obviously be nowhere as good as a real vector monitor, making a tiny, shoddy XYZ vector display from a Watchman just appeals to me. People have done X-Y successfully with them already.
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Finally got the transformer I ordered back in March, so now I’m just a few connectors away from having the power supply to some day build a 12v Serge/CGS system. Should be pretty manageable from here on out, since if you go a module at a time rather than doing full panels, DIY Serge stuff is actually a lot cheaper than Eurorack.
EDIT: I guess I should probably use 4 conductor XLR so I can put the +5v rail on one of the pins to make it more format-neutral (Serge or Eurorack)
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really digging this !
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Working on a patch programmable fx unit and generally trying to broaden my horizons in terms of diy circuitry (experimenting with discrete sync separators/trying to sort out a posterizer or some other kind of cool effect without leaning on schematics)
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i love the aesthetic of your casing and labeling. are you stamping into the aluminum somehow? (asking because i have in the past been known to use sharpies and am not entirely happy with that method)
Yeah I use steel stamps:) best results have been with a normal hammer on a cinder block - sounds unpleasant looks satisfying
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