Come questo? http://www.ebay.com/itm/2-X-Electronic-Components-Phototransistor-L-610MP4BT-BD-/150558658190?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item230dfece8e oppure è meglio questo? http://www.ebay.com/itm/LOT-20-LPT2021-NPN-SILICON-PHOTOTRANSISTOR-LED-LIGITEK-electronics-co-ltd-/280932716067?pt=LH_DefaultDomain_0&hash=item4168e50e23purtroppo devo acquistarlo su internet...