À la nuvistor

[Clondike Clad]

Originally Posted by Max

Welll... I must say that in some applications tubes are fairly better still today.
The problem is that semiconductors technology never really solved that issue of stability...

As an example... I made many years ago an oscillator for MD using common fets... I made everything absolutely by the book... considered controlling the current and making feedbacks , but , at the end, I tested the oscillator under various conditions and found that was absolutely instable vs temperature, no matter compensation strategies I tested (many).

I've then redesigned using small tubes , 6.3V powered and got perfect , stable sinus , no matter if I also swing an hairdryer near the osc module...
The MD was rock steady, then I learnt that for some stuff... better using old tubes than newer stuff.

About stability, experience say me that mosfets are good... but tubes are BETTER.


Kind regards,
Max

Yes that is true,BUT use for lrl it is a joke.
Keep on it Max you are doing a good job on this LRL site.