PuMa, a digital Pulsar Machine

¹ Astronomical Institute “Anton Pannekoek”, Kruislaan 403, 1098 SJ Amsterdam, The Netherlands
² Instrumentele Groep Fysica, PO Box 80004, 3508 TA Utrecht, The Netherlands
³ Astronomical Institute, Utrecht University, PO Box 80000, 3508 TA Utrecht, The Netherlands
⁴ Netherlands Foundation for Research in Astronomy, PO Box 2, 7990 AA Dwingeloo, The Netherlands

Corresponding author: M. L. A. Kouwnhoven, M.L.A.Kouwenhoven@astro.uu.nl

Received: 16 July 2001
Accepted: 22 January 2002

Abstract

We have designed and constructed PuMa, a pulsar machine that has both a baseband recording and a digital filterbank mode. Its design is based on the use of digital signal processors (DSPs). Their operation is controlled by software, which makes PuMa reconfigurable, flexible and easy to operate. The maximum number of channels in the digital filterbank mode is 32 768 over a bandwidth of 80 MHz. This makes PuMa suitable for pulsar observations at low sky frequencies. The maximum bandwidth in baseband recording mode is two times 10 MHz. The machine was installed at the Westerbork Synthesis Radio Telescope in The Netherlands in 1998. We discuss in some detail PuMa's technical properties and capabilities. Recent observations, a sample of which are presented here, demonstrate its capabilities and that it is performing up to its specifications.