Peter,Keith, I've seen plenty of adapters to use the 6GH8A in place of the 7199 and have wondered if this same adapter can be used the other way around. If not, I don't recall seeing adapters specifically for using 7199 in place of 6GH8A? Or, did I just miss them?
Referring to the previous post about modifying the PCB, as far as the ground plane and plated-through holes on the PC board, as long as the board is just two-sided with no internal layers, I would think it should be possible to make orderly cuts and jumps in the foil so that 7199 can be used directly with no adapter, if desired.
I was primarily concerned about differences in related component values, especially the resistors, in switching between 6GH8A and 7199. For example, Dave Gillespie uses different resistor values for his drop-in replacement board for the SCA-35, the reason being his board uses 6GH8A in place of the 7199. Note the description of the PC-10A Output Board Set here: http://www.audioregenesis.com/ Have been wondering if something similar might apply if swapping these tubes around in the Stereo 70 or its variants like the AVA Ultimate 70 / Ultravalve.
http://hardware.ui3g.com/ You can find some pcb manufacturer on this website. I think this website is very useful for electronic engineers.Keith, I've seen plenty of adapters to use the 6GH8A in place of the 7199 and have wondered if this same adapter can be used the other way around. If not, I don't recall seeing adapters specifically for using 7199 in place of 6GH8A? Or, did I just miss them?
Referring to the previous post about modifying the PCB, as far as the ground plane and plated-through holes on the PC board, as long as the board is just two-sided with no internal layers, I would think it should be possible to make orderly cuts and jumps in the foil so that 7199 can be used directly with no adapter, if desired.
I was primarily concerned about differences in related component values, especially the resistors, in switching between 6GH8A and 7199. For example, Dave Gillespie uses different resistor values for his drop-in replacement board for the SCA-35, the reason being his board uses 6GH8A in place of the 7199. Note the description of the PC-10A Output Board Set here: http://www.audioregenesis.com/ Have been wondering if something similar might apply if swapping these tubes around in the Stereo 70 or its variants like the AVA Ultimate 70 / Ultravalve.