To get to the calibration menu, you have to press the Scale & Offset key while turning power ON.
Then press the Scale & Offset key until CODE: is displayed.
Then you can access the menu list.
Use the arrow keys to get to the timebase cal menu item as mentioned in the previous post.
At this point, wait for the timebase to warm up, the longer the better.
I usually run it at this point over night so I do not have to cycle power after the oven is warm.
If you want, you can connect the 10MHz reference to the counter channel A input and watch the warmup as the counter display approaches 10.000000,0MHz.
Note: early versions of the counter do not access the menu in the above manner.
The CAL menu is accessed through the UTILITY menu.
Also there is no security on the CAL menu in older units.
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