When can an oral statement be used in lieu of a written affidavit?

When an oral statement is used in lieu of a written affidavit, it need not be transcribed prior to the issuance of the warrant. The purpose of transcription is "to make the transcribed statement the equivalent of an affidavit if an accused challenges the validity of the warrant under procedures[211 Cal.App.3d 338] set forth in other sections of the same chapter. (Pen.Code, 1538.5.) The transcription requirement of subdivision (b) of section 1526 is not a condition precedent to issuing a warrant, and that duty, like the requirements of certification and filing with the clerk, may be performed at a later time so long as it is done promptly and the transcribed statement is available to any accused who wishes to challenge its sufficiency and the validity of the warrant." (People v. Peck (1974) 38 Cal.App.3d 993, 998-999, 113 Cal.Rptr. 806, fn. omitted.)