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joebog1 · 7th Mar 2018, 4:37 am

Thank you Hugo,
As the value of the resistor is quite small ( even 2K4) I hadnt thought at all about the capacitance the 12BH7 has to drive. I really dont like "anti oscillatory" resistors at all, and in my circuit redraw I have deleted the plate resistors. I will retain the screen grid resistors though, and have even thought to increase them to something more like 470R.
I was thinking it will give a modicum of relief to the screen grids, which are not really rated to about 400 volts of HT, albeit in ultra liner mode. I feel that this amp will take a little ironing out to get it really working well.

Thanks for your input

Joe

7th Mar 2018, 4:37 am	#29
joebog1 Banned Join Date: Jun 2015 Location: Mareeba, North Queensland, Australia Posts: 2,704	Re: Golden Ear Laboratory Amplifier Build Thank you Hugo, As the value of the resistor is quite small ( even 2K4) I hadnt thought at all about the capacitance the 12BH7 has to drive. I really dont like "anti oscillatory" resistors at all, and in my circuit redraw I have deleted the plate resistors. I will retain the screen grid resistors though, and have even thought to increase them to something more like 470R. I was thinking it will give a modicum of relief to the screen grids, which are not really rated to about 400 volts of HT, albeit in ultra liner mode. I feel that this amp will take a little ironing out to get it really working well. Thanks for your input Joe