How to make a Timer - that measures without any "jumps"

There are several different types of timecode but you'd have to google that for specifics and history etc.   It doesn't matter in this case.

In a way ( sorta ) timecode is like military time … so when starting out it looks like 01:00:00:00  which means hours minutes seconds and FRAMES.

Starting out with 01 means that you are beginning the FIRST HOUR of time. It does NOT MEAN you already have one hour recorded.

It goes up to 24 hours and starts back at ONE, more or less.

Here is timecode like you have that shows the play head ( CTI ) at the 23rd frame of a film shot at 24 frames per second ( actually it's shot at 23.976 but that's another issue not worth going into ).  You can see by the image it is at the 23rd frame.

Then, when I advance the play head ( CTI) one more frame it goes to 1 second and 00 frames....

Therefore, if you think about 24 fps, and think about how much time you have to deal with ( 1/2 second would be 12 frames ) you may be able to do most of your work without using the timecode for audio which limits what you can do with cuts, because you can't cut the middle of a FRAME.  Know what I mean ??

Change the time code to Audio Units:

Work with timecode in Premiere Pro