Help deciphering abbreviated terms in technical manual
Quite likely: DECOUPLER

Source

Remove the decoupling capacitor 'A' nearest to 1C1

Part list:
Item Part No. Description Qty Remarks
92     0680,100 CPCTR DCPLR 33/47n AX 12V 39 'A'

From other part lists, it is said to be a SMD component.