[CA] [CA11] Adjust frequency on a CP470

[Daybreaker]

Good morning,I have a CP470 to a B175L. I want to run 41kh fixed. I am guessing that I choose the 50kh in the Sonar menu.Then go in an adjust the frequency to minus 18%??? Will this get me to 41kh? If so,is this accurate.What is the proper adjustment? THANKS, Capt.Mike

[Chuck - Raymarine - Moderator]

Welcome back to the Raymarine Forum Mike,

The procedure which you have identified is correct. However, the accuracy cannot be guaranteed .... but be should be in the ball park of 41kHz.

[Horsemackerel]

I have been wondering the same thing for some time. I currently have a Axiom pro RVX 16 connected directly to a B275 LHW (no CP470). If I'm understanding this correctly from what Mike and yourself have posted, with my current configuration, if I select 200kHz fixed (this transducer has a range of 150-250kHz on the high kHz) then I would only have a usable + or - 25% since -25% equates to 150 and +25% is 250. Is that correct? If I use -50% it will have no meaningful difference than -25%?

Is there any chance a future software update might display frequency instead of percentage?

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Horsemackerel,

The frequency adjustment percentage will increase or decrease from the center frequency of the transducer's range. Accordingly, should a CHIRP transducer have a range from 150-250kHz, then it's center frequency would be 200kHz. Increasing its frequency by 25% would cause the resulting transmitted frequency to be 1.25 x 200kHz, or 250kHz. Accordingly, increasing the percentage above 25% or decreasing the percentage by more than 25% would result in no additional increase or decrease t the transmitted frequency.

As the resulting frequency is an approximation, it is unlikely that a system change would be implemented to have the operator specify the desired frequency, as is may imply greater accuracy in the transmitted frequency than is actually supported.

[Horsemackerel]

Thanks Chuck. I appreciate your quick reply and clarifications - much appreciated.

[Chuck - Raymarine - Moderator]

You're welcome.