Nila is right. We need photos.
The amount knives with two blades in an almost countless amount of configurations that have yellow scales makes this question near impossible to answer unless you can provide some of the following, and the more the better.
A: a photo of the stamp on the base of the main blade (tang stamp)
B: a photo of the knife as a whole
C: a photo of the shield (the gold disc)
D: you tell us what it says on the tang stamp and what is on the shield, a tree, words, a dog's head...
E: is rusted/patina'd at all?
But on a guess and Only due to the round shield, I was thinking a Bear & sons trapper:
A boker tree brand:
Or a Moore maker (the bottom knife pictured):
The top three knives, in total, show a trapper pattern and the bottom one is a muskrat jack.