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.
I have a hammond power transformer with a 5V 4A secondry that I want to use with the 5AR4. Only problem is that the 5AR4 is rated for 5V 1.9A. Can I use the 4A tap anyway or what can I do to drop the current to 1.9A? Thanks in advance.
But, it is likely that you will get a little more than 5V from the winding if you only draw 1.9A, particularly so with a Hammond which seem to run a little high anyway, so you may want to measure to be sure you are within the tube's specifications.