[Milsurplus] Germanium to silicon

[Frank]

Ray Fantini wrote:
> Beware! lots of old germanium circuits relied on leakage
> for bias. I have replaced germanium with modern
> transistors in dividers and primitive logic gates and
> they sometimes work but cannot imagine what would happen
> in small signal circuits. although the internet is full
> of articles on how you can replace all the tubes in a
> radio with a couple fets and get equal performance so I
> am told anything is possible. Ray Fantini KA3EKH
> 

I did not know that there was such a difference between 
germanium and silicon based devices. I knew there was a 
difference and that silicon won out, but I had no idea that 
the additional leakage of old germanium devices became a 
design criteria. A bad design criteria.

My personal view of folk trying to 'solid state' a good tube 
design is that they are nuts.  No, there is no way to 
replace all the tubes with fets and get equal performance. 
Anyone trying is out of their mind.

Accept the tube circuits for what they are and do.  If you 
want a solid state version, then design one from scratch. 
Don't mess up a good vacuum tube design with solid state 
devices.

As for stuff you find on the internet, yes, beware.  I find 
stuff that is an obvious spoof.  I can recognize it as 
comedy, someone less knowlegable might think it is real.

Even the stuff that is not purposely spoofed may not deliver 
the goods.  Articles that are long on theory and short on 
results are suspect.  If the proof is left up to the 
student, then it is pretty certain that the author either 
has his tongue in his cheek or his head up his ass.

Regards,
Frank Kamp