The Wildlife Acoustics new EM3 bat detectors is now available from nhbs at a tad under £1000. There's a lot of technology in there and I haven't got to grips with the full specification yet, but it looks like full spectrum 16 bit 384 kHz sampling rate streaming to SDHC card, plus being able to listen in frequency division and heterodyne. The big difference is that it also has a screen that shows spectrograms in 'real' time. Not sure how useful this would be in the field compared with off-line analysis in batsound or similar, but it certainly looks good! It's not the first sound analyser for bat echolocation to be able to give a visual output in the field mind you. That honour goes to the Ultrasound Advice 'PUSP' or portable ultrasound processor which has been available for well over ten years now. The technology is looking pretty long in the tooth now, but it's still a very flexible instrument, especially for ultrasound output in the field.

EM3 bat detector