Agilent U1401A U1401B, Escort 2030 calibration

[Rufus]

Anyone know about calibrating these?

I have a U1401A. The manual only tells you how to calibrate the output and thermocouple input. The U1401B manual details full 'closed case' calibration but lacks important detail. The U1401A appears to support the full calibration described in the 1401B manual.

The problem is the U1401B manual says :-

3 To enter the calibration mode, press [AC] and [dual] for
more than one second. The primary display will indicate
CHEEP.
4 Press [Hz] to enter the input calibration mode.
5 Turn the rotary switch to the “Test Function” position as
shown in the adjustment table.
6 The primary display will show the corresponding
reference value of the Cal item.
7 Configure each Cal item.
8 Use the up or down arrow keys to select the Cal range.
9 Apply the input signal shown in the Input column of the
table.
10 The secondary display will now show the value of the
input voltage that is needed; press the HOLD button to
switch between the Offset and Gain values.
11 Repeat steps 5 through 10 for each adjustment point

This meter sort of does the right things but the instructions don't tell you what to do when you have applied the required calibration value. It seems you have to press the [Hz] key to enter the calibration value, or perhaps a long press or perhaps a long press leaves calibration mode. Anyone know?