Ewww. Erector Sets meet Electronics!

I’m guessing the “joints” are screwed together and not just a press fit.
Chasing down a cold solder joint is enough of a problem, I can’t imagine introducing a bunch of noise making points would ever be that popular among audio engineers.

Hey, maybe one of those “artsy” tube amp makers around these days might pick up on this. I can just see it – silver plated girders and metric connectors.

Hello,
soldering was quite a task in the twenties. Electrically heated
soldering irons for “everyone” came up during 30ties.
Georg

Since those joints were not soldered I could sure see problems with oxidation in the future.

@KD5ZS Even with the oxidation problem it was probably still better than using corrosive plumber’s flux, bar solder and a copper iron you heated on the stove… as most people would have needed to do in those days.

It amazes me how anything worked at all before rosin-cored flux became commonplace!

One of the first things I remember from High School electronics class: “No acid core solder!”

tube circuits worked with higher voltages than are common in transistors,
and thus were more tolerant of a few extra ohms here or there.

I first learned about acid core solder when I assembled a printed circuit amplifier using solder and paste flux given to me by my uncle the plumber.

It didn’t amplify, just hummed and occasionally smoked — then, they told me that the flux I used was conductive.

It looks like early bread boarding before the nice, neat bread boarding. I’d probably solder up the joints after being sure everything works. Thermal expansion and vibration would loosen up those joints really fast.

Modern breadboarding supplies
http://www.cir.com/part…

The funny part for me is I remember punching out parts from coils of ribbon like those, mostly pins for connectors.