I have two questions about autotune in the instrument Agilent 7890B Gas Chromatograph with 7000D MS Triple Quad. Type of autotune is EI high sensitivity autotune.
1) What is the acceptable range of the electron multiplier voltage (EM Volts) which should appear on autotune?
2) What is the acceptable range of isotope ratios which should appear on autotune for mass 69, 219, 263, 414, 502?
Typically , once an EM is around 2500 volts, its time to order a new one and plan to replace. In general, some tuning guidelines are below. As you can see, there is a broad range. Generally, if the tune passes the instrument is ok to use, but may not be performing at its best.