[Boatanchors] Charles Smith works on the R-390A. A lot!

[William Cromwell]

Hi,

My own idea about this - it seems like doing this requires a lot of 
effort to get it anything like *right*. For that much effort we can 
scratch build a new, solid state rig starting with the block diagram of 
an original vacuum tube design. I have changed the power supply 
rectifiers to solid state with great success and I used a solid state 
audio amp to replace a completely fried tube stage - leaving the 
disconnected, ruined audio amp for possible later reconstruction.

The bugaboo for using vacuum tubes is the power dissipated in those 
heaters that contribute absolutely nothing (*NOTHING*) to the signal 
processing. But the tubes won't work without wasting all that energy. 
Nevertheless, I still have and use gear with vacuum tubes. Even worse, I 
have some construction projects underway that include - ahem - vacuum 
tubes. I have acquired a batch of "battery tubes" to ease my conscience 
regarding the wasted power. Those are not practical in every circuit but 
they do behave like - um - vacuum tubes :) I have been investing more in 
solid state and even in SMD arts. Heaven help us!

73.

Bill KU8H

bark less - wag more

On 8/20/22 06:42, Bill Meara via Boatanchors wrote:
> This may be too much for some of you, but I found it really interesting:
> https://soldersmoke.blogspot.com/2022/08/trigger-warning-solid-stating-old-tube.html
>
> 73  Bill N2CQR