Decoupling capacitor values

Hello
Me again about my ultrasonic range finder
Just wondering what would be the best value of capacitors to use when decoupling the supply and maybe if reqired across the vcc and gnd of the reciever amplifier. Had many problem a the first attepmt on building the design on coper strip (works better on breadboard but want it on cooper strip). Lots of leakage was present first time and I am now thinking about laying it out differently on the board ( using space better on board, wider power rails etc) but my main question is what are the best values to use when decoupling. The frequency of operation of ultrasonic is around 40kHz.
Thanks for any help

I always use 0.1uF or 0.01uF, plus electrolytics here and there - particularly at high current points - like the ultrasonic output stage.

decoupling caps

hi,

i would suggest you use a multilayer ceramic cap both on the input/output with a value of 0.1uf and electro caps of at least 100uf.