  Binary millisecond pulsars (MSPs) provide several opportunities for research
of fundamental physics. However, finding them can be challenging. Several
subdwarf B (sdB) binary systems with possible neutron star companions have been
identified, allowing us to perform a targeted search for MSPs within these
systems. Six sdBs with companions in the neutron star mass range, as determined
from their optical light curves, were observed with the Green Bank and
Westerbork radio telescopes. The data were searched for periodic signals as
well as single pulses. No radio pulsations from sdB systems were detected, down
to an average sensitivity limit of 0.11 mJy. We did, however, discover a pulsar
in the field of sdB HE0532-4503. Follow-up observations with the Giant
Metrewave Radio Telescope showed that this pulsar, J0533-4524, is not spatially
coincident with the sdB system. The pulsar has a relatively low magnetic field
but still emits giant pulses. We place an upper limit of three to the number of
radio pulsars in the six sdB systems. The non-detections may be explained by a
combination of the MSP beaming fraction, luminosity, and a recycling fraction
<0.5. Alternatively, the assumption of co-rotation between the MSP and sdB may
break down, which implies the systems are more edge-on than previously thought.
This would shift the predicted companion masses into the white dwarf range. It
would also explain the relative lack of edge-on sdB systems with massive
companions.
