Good afternoon...

Anybody know where I can find some formulas or design information for
designing coax traps for a dipole?

I've seen some articles on coax-trap antennas but the traps they use are
too big. I need to make some traps for 40 meters that are narrower (but,
longer is OK) than the ones I've seen in the articles.

(A thought I had was perhaps using RG-174 instead of RG-58 ... these will
be used at low power only, 10 watts max)

High Q and narrow bandwidth is OK. These traps only have to resonate at
one specific frequency.

Any thoughts or advice?

Thanks...