Balancing by Fund

Hello,

I would like to know how to handle mutli fund balancing in GL.

Let's say  there is only one bank account and one default fund attached to the bank account. - one fund 123

Source of receipts may be several like lets say A, B,C - each of these receipt sources have different revenue funds associated with them.

Currently any receipt from source A or Bor C gets posted as a debit to the default bank fund 123 and the credit is posted to the revenue account.

How can we have the debit entry posted to the specific fund associated with the receipt source instead of the default bank account  ?.