BradTheRad,
Thanks for the detailed options. As is too often the case, I may be misunderstanding your understanding of how little space is in the 'Tiny SA' spectrum analyzer? Even with the battery removed the total available size is 6.69" X 4.72" X 2.56". The maximum available space is less than a sewing thimble! So a, "... few feet of #22, #24, or #26 wire .... probably would NOT fit.
I always encourage people to ASK rather than not 'know', so I'll ask! Looking at your 4 diagrams (options) it appears 1.3 or 1.2 A is ?total current flow? Since considerable current flows through the 4.1 / 4.2 V tap off how - why do you label so much current flow through the dropping circuit to ground? I've not measured average current flow through the SA. I'd guess 350-700mA so what am I failing to take into consideration?
For the 3.3 Ohm resistor(s) in diagram #2 the parallel combination of a 5 & 10 Ohm 1 W resistors should suffice/work. That only leaves the diode. Will any 1 W Silicon diode work? At least I have several on hand.
AGAIN, thanks for your interest, assistance/help AND patience! Remain WELL & be SAFE!
Mrs. RA