Sorry nitro, but I don't think it will be that simple. Coneangle will vary with different transeducers, and 200 kHz might not have the same angle on all Airmars 'ducers (I'm in fact pretty sure it is not, ref the big CHIRP-thread on the THT-forum). Depending on wich CHIRP-range (L,M,H) you use, 200 kHz might not be an option at all. (Although for most anglers it will, only the ones fishing extremely deep and using only L will be without 200 kHz)
Airmar brochure:
www.airmartechnology.com/uploads/brochur...CHIRP_booklet_hr.pdf
The TM150 is not in this leaflet, but is/ will be the OEM 'ducer for both Garmin and Lowrance.