how can i adjust the PW-0268 ultrasonic sonar ranging IC frequency system ?

Some Maxbotix sensors can reach 10m - if you can afford them.

i will try it tanks douglas.

and the max range we want to achieve is 10m

thanks michaelkellett;

if u read the data sheet u can find that all the parameter are depend on the frequncy clock system.

however , i'm using the SRM400 is a sonar ranging module that use 400EP14D transducer and the max range is 150 cm.

Why do you think that increasing the frequency will increase the range ?

On the data sheet it asks you to contact the chip manufacturer for an 18m capable design which suggests that the standard circuit won't do.

What range are you achieving now and what transducer(s) are you using ?

MK