The ORTEC Model 269 Photomultiplier Base structure is a mechanical assembly and resistive voltage divider network, with appropriate capacitive-decoupling for operation of 14- and 12-stage PMTs that fit standard 20-pin sockets, including:
- Hamamatsu R1250.
- Philips XP2020, XP2020Q, XP2040, XP2040Q, XP2041, XP2041Q, XP2212B, XP2230B, XP2233B, XP2262B.
- EMI 9813K.
Internal trimmer controls permit optimum adjustment of the voltage distributed to the focus and deflection electrodes and to the last dynode.
All of the above photomultiplier tubes are capable of producing high-current timing output pulses, and the Model 269 PMT Base structure complements the tube characteristics by maintaining the excellent pulse fidelity through a wide range of signal currents.
Two outputs are furnished from the Model 269: the negative signal from the anode is intended for timing or single-photon counting, while the linear signal from the tenth dynode is for energy measurements.
Each of the last four dynodes is also available externally through contacts of the Auxiliary connector. These connections permit external voltage stabilization for the last four dynodes of the PMT.