Talking about old radio books of the 1920s in the Netherlands, with triode radio tubes and more

Описание: Please read the description/textbox first.

Because this is an informative/history video I don’t want to give more comments. Say everything is told in the video. Relevant earlier video is here    • 1 tube AM radio circuit from the 1920's - ...  

The history of the Dutch radio since 1920 is (like all over the world: US, Germany, Russia, Eastern Europe, UK, Brazil, Indonesia, China, etc.) a “sea to drink”.

Here I only focus on a few Dutch books of the 1920s where practical radio circuits (often with only triodes, one or 2 in a row) were published. Perhaps the video is somewhat sloppy, but the essentials of these early 1920's radio's (often with only triodes) are told.

Interested in United States radio circuits? And much more about electronics (not only about radio tubes)?

Go to the YouTube channel of “Allamerican5 radio”; Richard has published a lot of radio tube circuits, with all ins and outs.

He is a specialist in this matter and gives very precise explanations about how radio tubes work. Has also a free book about radio tube technology.

Link is
   / @allamericanfiveradio  

The classic idea of early (1920’s) radio reception circuit was/is: a triode tube radio, where (sometimes, not strictly necessary) a part of the radio energy was pushed/sent back from the anode (= the amplified signal) to the grid of the triode/the tank circuit.

That was done via a tuning capacitor (or in another way), pushing up the radio reception on frequency “x” to a high level.

That was the so called “backcoupling” or ”regeneration”. Or (in modern terms) a “Q amplifier”.

Q stands for the quality of the (radio reception) coil, backcoupling pushes the Q (coil quality) up, not in a passive but in an active way.

In these cases radio reception in the HF band (300 KC-30 MC), say via “tuning” the radio tube (the triode) to a sharp certain frequency band, got much better.

The backcoupling principle (via a coil or a capacitor) is used (by the way) everywhere, also (e.g.) in audio amplifiers (20 Hz-20 KC) where a certain part of the audio band is/can be coupled back to the input.

Which part of that audio band somewhere between 20 Hz and 20 KC is extra amplified? Often the low frequencies (the bass) need to be.

That depends on the value of the backcoupling capacitor, or even an R-C combination (filter), tuned to frequency band “X”. Everywhere visible in old (1970’s) and new (2023) audio schematics. More info is in 1970's books or in modern (2022-2023) audio circuits. These principles are still overall used in electronics.

That (thus) in that case means that a specific part of the audio band (somewhere in the 20 HZ-20 KC range) is amplified extra (=extra fierce). Often bass.

That also can happen with different values of back coupling capacitors in amplifiers in the order of 20 Hertz to 30 MHZ.

It tells us something about “backcoupling” and its positive effects. Negative effects (not in electric/electronics terms): when the backcoupling is to fierce or not “phase-right” the amplifier (tube/transistor) starts to oscillate.

Phase differences (phase shift) can occur everywhere in an electronic circuit, by the way. Due to the components and/or the electronic setup and/or the practical way that the circuits are/were made on the board.

Thus: sometimes we need that oscillation, so in that case we have made a radio (or audio frequency) oscillator. The wave forms will differ in their form/shape, they depend on the time-elements in the electronic circuit and the amount of amplification via the transistor(s) or tube(s).

Many HF and audio oscillator circuits are on my YT Channel, go to the looking glass on my channel trailer (Radiofun232 on YouTube) and type keywords to find the schematics (“oscillator” or “generator” are the key words).

My You Tube channel trailer is here:    • Radiofun232 on YouTube, find working & tes...   When you search, search always “NEWEST FIRST” to get the right overview.

You can also search via the “looking glass” on my Channel trailer via keywords like ”audio”, “radio”, “amplifier”, “filter”, “Shortwave”, “transistor”, “FET”, “oscillator”, “generator”, “switch”, “schmitt trigger” etc; so the electronic subject you are interested in.

My books about electronics & analog radio technology are available via the website of "LULU”, search for author “Ko Tilman” there.

https://www.lulu.com/search?adult_aud...

I keep all my YT videos constant actual, so the original video’s with the most recent information are always on YouTube. Search there, and avoid my circuits that are republished, re-arranged, re-edited on other websites, giving not probable re-wiring, etc.

Some persons try to find gold via my circuits. I take distance from all these fake claims. I cannot help that these things happen. Upload 14 May 2023.