here is the info on the omegaforce S45:
Omegaforce S45 Service Manual
before you do anything though; you should consider a couple of possibilities.
if the radio used to put out the wattage you consider "correct", but now it puts out less; you may have an antenna problem or some other problem that is external to the radio.
make sure this is not the case before tuning anything inside the radio.
if the radio hasnt put out the power you think it should since you got it, you need to remember that this radio was tuned at the factory for a freq. range of 28-29.7 mhz.
if you did the channel mod and nothing else, then your radio would not be "peaked" on the CB freqs and would put out less power there than if you were up on 28mhz.
so if you follow the alignment procedure that i linked you to, you will need to adjust the freqs they tell you to use for the range you want.
like, if they say "set radio to 28.500mhz" and you want to use your radio on the CB band, you should set your radio to 27.205 or some other freq that seems to be in the middle of the band you want to use.
make sense?
hope this helps,
LC