Small, good price, reduced to the minimum: Mini batcorder
The Mini-batcorder is a cost-efficient, small and rather simple solution for automated detection and recording of bats. The Mini-batcorder is reduced to the absolute necessary for that task. It therefore is especially well suited for conservation by NGOs, but also for use at locations with high frequency of passers by and thus possible thefts. For high compatibility files can optionally be stored as Windows Wave instead of batcorder RAW files.
The Mini-batcorder comes without display - the first and most obvious difference to the normal batcorder. It has a single key to turn it on or off. LEDs indicate battery status, available space for recordings and clock or gps coverage. GPS will be turned off after successful acquisition of a position to save power. All settings can be adjusted using a free supplied software for your Mac and for Windows. To download data as well as to charge the battery you use a standard USB connection. In addition you can supply power using a USB powerbank to prolong its standard runtime of two days.