• 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.

Oscilloscope Probes for Tube Work

I have just purchased an old Tektronix 465B and need to get a suitable set of probes for working with tube gear.

In Building Valve Amplifiers, Morgan Jones writes: "Typical X10 probes can only withstand < 200V, and the HT at the power amplifier output stage is likely to be >300V. In addition to your X10 probes, you will also need an X100 probe that is rated for high voltages."

Having picked up some probes rated "<600VDC + Peak AC", I thought I was pretty well covered for anything with a B+ of 500V or less (giving myself a 20% margin of error). Am I missing something?