German Road Sign

I'm pretty sure it's a schematic for a basic super-heterodyne receiver. Just need to measure the frequency of that blue "sign"-wave.

No, not any version of super-het. However, it sure looks like the German version of a Spitfire wiring diagram to me. Including water/corrosion indicated by the wavy blue lines.

Being German (and driving an LBC), a little translation: this is a roadside map is for detours around the region, in case of heavy traffic. Specifically the Neckar Valley. The blue sign waves are the Neckar river. It's a windy day, apparently!

Having said this, I'm not sure I would remember this little map once stuck in traffic!! This sign happens to be right outside Heidelberg - instead of sitting in traffic, I would perhaps rather enjoy a libation (i.e. the famous Fass). Or, keeping things car-related, spend the day in nearby Hockenheim.

Here in Pittsburgh we have the "rings"... blue ring, green ring, etc. https://en.wikipedia.org/wiki/Allegheny_County_belt_system

Have fond memories of navigating this nightmare in the 1980s. My dad met someone in the same lane as him going in the opposite direction. They were obviously local and use to that situation. You could go either way around the large center roundabout. Going from exit 5 to 6 you could go clockwise or counter clockwise. It could get very confusing.

David

https://www.youtube.com/watch?v=wVeAhmvNFIU

Funny you should post this sign for a round-about of round-abouts. I nearly did too! I've driven this one, and one that is considerably larger (and the larger one was easier).

Had not thought about that part of London in a long time.
Last time I came around it I was driving a Morris Alegro that burnt almost as much oil as it did petrol/gas. Found that one of the pistons was missing a chunk. Got some rings, a single piston and rod assembly from a junk yard. Cleaned up the bores with a honing tool and it did another 25000 miles.

David

Looks to me like a bistable multivibrator.