• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

1U5 amplifier design, Newbie

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I making an amplifier using a 1U5 battery operated tube. Being a Newbie I'm a little baffled. Looking at my test circuit #1, I am getting about -0.5V dc on grid 1. If change R1 to 10K the voltage drops to about -0.05V or so and the voltage on the plate drops to about 30V. Where is this voltage coming from and how do I deal with it? I want to keep the input impedance high so I can use a small decoupling capacitor C1.
Also, can I make the tube behave more like a triode by using circuit#2 or circuit #3? Thanks for your help.
 

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