This is a list of cards
with known errors. If you find any errors not listed, please inform me.
All of the cards listed above have either wrong filament voltages or wrong pinouts. These errors are easy to spot. It stands to reason that other errors exist which are not so easy to spot, such as proper meter sensitivity. Please report any suspected errors.
The following tubes all have one or more 12AX7 triodes in the envelope. Hickok used the published operating point of +100V plate and -1.0V grid bias for these tubes. The problem is the manufacturers started insuring their tubes adhered only to the other published operating point, which is +250V plate and -2.0V grid bias. As a result many good 12AX7ís test low on the Cardmatic.
As of database version 1.05, the triode section(s) of following tubes have all been modified to use the latter operating point: