Bat-Hat

The Bat-Hat is a microphone extension cable and protective shroud for the Anabat ultrasonic bat detector. It allows the equipment to be used in field settings where it is necessary to protect the microphone from the weather, and where the microphone may need to be installed at a distance from the detector. This might be a wind turbine installation, or it might be a natural setting.

The extension consists of a protective shroud for the microphone, a reflector, and mounting bracket, an encapsulated preamplifier/line driver, a microphone cable of up to 100 meters length, and a standard DIN connector that plugs into the Anabat detector.   The photo essay on this page shows how the Bat-Hat is constructed and deployed.   This arrangement is adapted from the pioneering work of Tony Messina.

Resources:

Titley Electronics in Ballina Australia for Anabat systems.
    http://www.titley.com.au/
EME Systems' in Berkeley California for Anabat microphone extension cables and accessories:
    http://www.emesystems.com/bat-hat.htm
Archive of Tony Messina's original constructions:
    http://home.earthlink.net/~nevadabat/

Also available from EME Systems is a weatherproof enclosure (NEMA 4, gasketed) to house the Anabat, and Z-caim recording device, or one or two unitary SD1's along with a sealed Pb-acid battery, a power controller/solar battery charger, and even a logger to record weather variables and to maintain the operation on at night and off during the day.

-------------------------------------------------------------------------

Bat-Hat Bracket Configurations:

The bat-hat bracket is available in several different configurations, and you need to specify one of these when ordering.   These have evolved over time to meet different needs for mounting.

The brackets is constructed from aluminum bar stock, 1" wide and 3/16" thick.
The reflector is a 6" x 6" polycarbonate plate
1a) the cap is vertical and the refector is at 45°.   The main sound entry direction is from "straight out" and reflection straight up into the microphone.
1b) the bracket has an additional 15 degree bend above the hat, and the reflector ends up at 30° below the horizontal.   The microphone "looks" 15 degrees above the horizontal.   The acceptance angle is actually wide, not a narrow beam.
1c) the reflector is 15 degrees below the horizontal, so rain can still run off.   The main angle is high.

3b) this is like 1a, except that it has an additonal support member below the reflector. This is recommended in high vibration environments.

tripod mount) this is an angle bracket that has a 1/4"-20 threaded hole for a standard tripod mount, and holds the hat and the reflector. The tripod is not supplied, but it can be a standard model or a backpacker model, so long as it has the necessary bas to hold the weight.

Call or email if you have questions about the dimensions.   The most popular bracket is #1b.

bat-hat bracket diagram

2009 Bat-Hat price list (These prices will take effect on April 1st 2009):

BATHAT/xxx: Bat-Hat with preamp, shroud, bracket & reflector ..................................... $245 base price ea
-- + cable Canare 4e5c xxx ............................................................ @$2.25 per meter
-- or + teflon cable Belden 88723 xxx ........................................... @$5.00 per meter

-- bracket style 3b with extra support leg, ..........................................add $7.00
-- note, the number xxx after the / is the desired cable length in meters
-- We use Canare StarQuad-4E5AT highest quality audio cable
or Belden FEP-88723 teflon for highest weatherability and noise immunity
-- spare parts:
   reflector with SS hardware $10.00
     aluminum bracket 1a, 1b, 1c, tripod   $21
     aluminum bracket 3b $29
     shroud (coupler) with hardware $12.00

The following items are enclosures to hold the Anabat equipment, with batteries, solar panels and optional data logger for meteorological logging.

EFG1008BH: Fiberglass enclosure 8"x10"x4" .................................................................. $195 ea
     -- prepped with gland nuts, mounting hardware and blocking
      large enough to accommodate one Anabat+zcaim or one or 2 SD1s
         as well, B1207 battery, charger and optional data logger
     -- if using SD1s, please specify if one or two will be enclosed in the box.

B1207: Battery, sealed Pb-acid 12 volt, 7 amp-hour ........................................................... $26 ea

AE1205: AE solar panel with mounting bracket, 12 volt, 5 watt ........................................ $95 ea
    -The 5 watt panel is adequate for summer and exposed locations.
or
AE1210: AE solar panel with mounting bracket, 12 volt 10 watt ...................................... $155 ea
-The 10 watt panel is recommended for winter or marginal solar
exposure locations.

CG1129BH: Battery charge regulator for solar to 12 volt sealed PbAcid battery ............... $85 ea
  -- low dropout float charger for efficient solar charging
-- also includes wiring harness to connect to battery, anabat, zcaim and solar panel.

----- optional data logger and accessories ---->

OWL2pe/TB215/BH   Data logger ................................................................ $335
  -- includes battery charger (the separate charger CG1129BH is not necessary)
-- includes wiring harness to attach to Anabat/zcaim
-- however, the OWL2pe cannot control the SD1-it is on its own
-- includes firmware for weather data logging and for potential Anabat/ZCAIM control.

vDrive: USB flash drive interface (new item, for easier met data offload) ............ $105
   Data collected by the OWL2pe is stored on the flash drive,
   And the data file carried to a computer with a USB port for rapid transfer.

optional sensors for data logging using the OWL2pe data logger:
SHT75PG: Sensirion temperature/humidity probe .............................................................. $95
DV6410: Anemometer, DAVIS 6410, with multimount bracket ........................................ $130
DV7852: Tipping bucket rain gage ..................................................................................... $75

Bat-Hat Photo Essay

	At the left, the Bat-Hat mounted on a pole. The microphone is protected inside the shroud. Bat calls bounce off of the reflector up into the microphone. This bracket holds the reflector in a horizontal position, so that it can receive best the calls that originate up at a 45 degree angle. Another bracket is available that accepts calls best from straight out on the horizontal. The bracket is aluminum and is held on the post by a SS hose clamp. The microphone is plugged into a standard DIN receptacle inside the shroud, and the cable at its far end has a DIN plug that connects to the Anabat detector. The capsule behind the microphone contains a preamp with 75 ohm output resistance that is capable of driving long cable lengths. Any of the Anabat microphones can be used, including the standard microphone that otherwise is incapable of driving long cables. The capsule is potted and sealed to prevent moisture entry.
Construction of the Bat-Hat capsule. This includes the following: DIN connector with a PVC mounting washer, sealed contacts preamplifier attached to connector and to the cable PVC capsule (Spears #429-005 1/2" sch40 straight coupler, cut to 1.5" length) PVC cap (Spears #448-020 2" sch40 threaded cap, center drilled/tapped PG7 ) Heyco PG7 gland nut Canare type 4E6S star-quad microphone cable to the desired length Heyco PG11 gland nut to seal the entry to the enclosure around the Anabat DIN 8 connector that plugs into the Anabat. When completed and tested, the space behind the preamplifier is sealed and potted with electronic grade epoxy. More details of the cable wiring can be found at http://www.nevadabat.com/
	This is a preamplifier mounted on the back of a DIN 8 receptacle. The LT1351 is an operational amplifier especially well suited for driving cables. The cable will be attached to the open holes. This preamplifier draws less current drain than the special "hi mic" that is sometimes used for long cable runs, 0.5 milliamp vs 4.5 milliamps. It also has a lower output impedance, 75 ohms vs 1000 ohms, that translates into a better response at high frequencies on long cables.
The microphone assembly screws onto the mating shroud (fabricated from a Spears #436-202, 2" sch40 PVC straight to threaded coupling.) The bracket is fabricated from 3/16" x 1" aluminum stock, and the reflector is a 4.5" x 4.5" polycarbonate square. Hardware is #8-32 stainless steel.
	Several bracket styles are available. See the diagram of possible Bat-Hat Bracket configurations on this page. One of the brackets shown to the left allows for a "45 degree" angle of sound acceptance, while the other (far left) allows for "straight out" sound acceptance.
Photos in the natural setting courtesy of Dr. William Rainey. These systems also include the enclosure mounted on the pole, next to the solar panel. The enclosure holds the Anabat, z-Caim, battery, data logger, and power controller.
	A NEMA 4 enclosure (rated proof against rain and spray) holds the Anabat and the Zcaim, along with a 1.2 amp-hour sealed lead-acid battery and an OWL2pe data logger/ power controller/battery charger. The controller is programmed to turn the Zcaim and Anabat ON 20 minutes before local sunset and OFF 20 minutes after local sunrise. Running the equipment only during the hours of darkness conserves the battery and allows the system to operate on a smaller battery. The data logger records the battery voltage as well as the external temperature and humidity, and optionally weather parameters such as wind speed and direction. Note that the microphone cable comes into the enclosure through a gland nut, as do the other cables. Power to both the Anabat and the zcaim are supplied via the controller, through the 12 volt input barrel jacks. There is also a connection from the controller to the Zcaim that implements the power control, remotely "pushing" the Power button on the Zcaim.
Temperature and humidity data are useful to assess environmental conditions. A 5 watt solar panel can maintain the system. The Zcaim/Anabat requires between 10 and 20 milliamps while in operation. This solar panel can provide 350 milliamps in full sun, but on dark days It may only produce 5 to 10 milliamps. The OWL2pe controller can adapt and shut down the system during particularly bad weather.