This tube is a reversed ECC832. So systems of 832 swapped.

A tube with two different systems inside, requires normally two cards, because settings are not the same and good / Bad limits are another too.

It would be possible to make such a dual card set for ECC823, but this is not needed, because just normal cards like for ECC83 and ECC82 can be used for the same purpose.

To test ECC82 part, use ECC82 card, and plug in only plug A1, and leave A2 open.

To test ECC83 part, use ECC83 card, and plug in only plug A2, and leave A1 open.