Improving Arecibo Observatory's Hardware

The Puerto-rican Ultimate Pulsar Processing Instrument (PUPPI) is a key backend for time-domain observations at Arecibo Observatory. PUPPI enables pulsar timing used for gravitational wave studies, single pulse studies of pulsars, searches for new pulsars, and allows in depth studies of Fast Radio Bursts (FRBs). Unfortunately, PUPPI is presently restricted to only certain Arecibo receivers due to its input frequency and bandwidth requirements. Here we present the design process, building, bench testing, and updates on the implementation of a one-channel breadboard of a new frequency mixer at the Arecibo Observatory. The function of the frequency mixer design is to translate a 1.1-1.9 GHz band to 0.8 - 1.6 GHz band, where PUPPI samples the data at the second Nyquist zone. When this seemingly simple device is fully implemented, it will allow for the further expansion of the abilities of PUPPI. Mainly it will expand PUPPI's frequency agility to higher frequencies from 4 to 10 GHz, by enabling it to work with many more of Arecibo's receivers. We hope this becomes particularly useful, now that a FRB has been detected at these higher frequencies. The Arecibo Observatory is operated by SRI International under a cooperative agreement with the National Science Foundation (AST-1100968), and in alliance with Ana G. Méndez-Universidad Metropolitana, and the Universities Space Research Association. The Arecibo Observatory REU is funded under grant AST-1559849 to Universidad Metropolitana