I hope everybody has seen this on Hackaday over the weekend…
It sounds really, really dirty, full of harmonics and… I kinda want to build one this week as a result!
Also, in this video, I’m pretty sure that the pots used for tuning are from an old, analogue CRT TV. I approve!
Very cool, sounds almost like an upright bass.
What a great sound!
Last time I saw electronics behave like that Boris Karloff got up for a boogie!
Reminds me of this…
Ha! That’s marvelous!
All this remember me this thread
I might have to, you know…
Oh yes! That was impressive, noisy stuff 
Hey there all, DrCockroach here and this passive synth has been a real giggle for me to learn on. My other main project is a wall sized 4 bit processor and so far has over 100 of my hand made Vactrol Led/LDR pairs so getting the hang of making them Lol Any ideas are surely welcome.
Watch the setting on the pot that feeds the right most LDR. V2+ is about 20volts and will get hot if not careful. I plan on adding a low value fixed in the line to avoid another meltdown XD
Oh yes, most all my parts go back over 40 years of collecting. My wife hates that.
That’s great! I’ve got parts that I’ve used from the other end of analogue TV broadcasts - this was where my office was 13 years ago and when they started pulling out the outdated broadcast equipment some pieces bounced off the top of the skip and dropped into the back of my car (a very curious thing to happen!)
I had an actual, honest-to-goodness Autocue for a while 
and still have various bits of studio equipment dotted around my 2020 office/workshop/cave!
"I just happen to back into the skip officer and all that stuff fell in“
Respect!
List the 'bits‘ you have and I’m sure we’d all have ideas.
It was one of the galleries that was being cleared out, so I’ve got the one half of the talkback system between the gallery and studio floor, a load of LED label things that went above the individual monitors (CAM1, CAM2, LIVE etc), the control surface for live broadcast effects (fades and wipes and things) and a panel full of push buttons with little incandescent bulbs in somewhere. It was all stuff that wasn’t needed once Carlton gobbled up all the individual broadcasters and formed ITV plc and they consolidated the actual broadcast in London.
Side note - there was a room labelled GMTV which was, unsurprisingly, where the feed for GMTV came in because there had to be switching mechanisms or something. This became the room where the whole ITV feed came in once Carlton did their takeover, but the onsite engineer mentioned that there was a kill switch for the feed that they could use in case there was a coup and Wales declared independence
Sorry, gone way off topic! It was an epic workplace, sadly torn down for housing now 
Well, this is my first dive into the world of building a synth and as I always do things in a strange way, how about a fully passive synth. No transistors, tubes or IC’s allowed. Well… perhaps as a audio amp if I want large loud speaker volume 
Think Vactrols but handmade…
A big thank you to Patrick Flett for the initial oscillator circuit.
They surely look like them. I’ve seen those in TVs I scavenged for parts.
