4 replies to this topic

[Robot]

I have read mixed reviews about the “Bat Listener” as a paranormal investigative tool. I decided to purchase, an expensive one,($250.00), from ebay.

The listener I purchased is dual input adjustable, sensitivity range can be adjusted from 15kHz to 150kHz. Output jack can send signal to a recording device, while earphones give “realtime” feedback.

I spent some time last weekend “playing” with the unit. I was amazed with the amount of “sounds” outside the human hearing spectrum. My Motorola Droid has a “dog whistle” application, that goes up to 20kHz, I used this for testing. The device is highly sensitive to “noise” from electrostatic discharge. Someone simply rubbing their fingers together is extremely noisy. I have not determined if this is electrostatic noise or some type of acoustic mechanism.

I found that: Many bird songs have “notes” outside human hearing range, Quiet door hinges can squeak loudly in upper frequencies. Motors and fans can generate many types of upper frequency harmonics, my little door latch chain links “ring” loudly.

I’m skeptical about the “bat listeners” paranormal use, but certain about it’s investigative environmental data gathering. It is good at hearing “normal” things humans cant hear. I may be more useful as a “de-bunking” tool.

Ill keep you posted with updates. Ill use the listener in the Sensor Array of my Paranormal Investigating Robot, (Gheist Strahlung) “Ghost Radiation”.

Parts arrive for Robot Construction this week, I should have some preliminary build pics next Monday.

Let me know if you have any “bat listener” experience. Thanks, Regards, John

[Old Guy]

Robot, on Apr 5 2010, 05:49 AM, said:

I decided to purchase, an expensive one,($250.00), from ebay.

YOWZA! I guess so! It *is* purdy, though.

As you're building a robot, did you disregard these for any particular reason?:
(Some are probably dupes.)

http://pw1.netcom.co...atDetector.html
http://user.itl.net/...er/BatDetector/
http://detector-sens...or-circuit.html
http://integraonline...n/detector.html
http://home.earthlin...TheBatShop.html
http://home.earthlin...ector/SBD2.html
http://www.btinterne...pentops/bat.htm
http://www.goldmine-...sp?number=C6899
http://njsas.org/pro.../sk207_sch.html
http://bertrik.sikken.nl/bat/tjerk.htm

I do have some expeience with bat detectors (and robotics). I've built most or all of the above and given them away. My favorite is the simplest radio-based detector.

Most of these are based on the Popular Electronics design:
http://njsas.org/pro...heterodyne.html

But still, if I had your money, I'd throw mine away!

[boatlesspirate]

I picked up a Belfry bat Detector as I was curious if EVP’s were the result ultra-sonic contamination. Although I was disappointed that the Belfry did not de-mux down the ultra-sonic sounds into our hearing range (it clicks away with the sound), like you I found that there was a lot going on that we couldn’t hear. I agree, I use it more for debunking things at this time. I have not captured any EVP’s in concert yet when the Belfry was triggered, but I did have an interesting thing happen on an outdoor daytime investigation. While doing an EVP session, the Belfry started clicking away at the same time my tri-field natural EM did. This was right when we were asking if someone could speak to us or let us know they were there. This went on for about 30 seconds and both meters stopped. I did not pick up anything on my recorder other than the clicking of the Belfry and the buzz of the tri-field. Paranormal? No idea . . . but I have no explanation yet. The jury is still out on this one.

[Robot]

Old Guy, on Apr 5 2010, 04:02 PM, said:

Robot, on Apr 5 2010, 05:49 AM, said:

I decided to purchase, an expensive one,($250.00), from ebay.

YOWZA! I guess so! It *is* purdy, though.

As you're building a robot, did you disregard these for any particular reason?:
(Some are probably dupes.)

http://pw1.netcom.co...atDetector.html
http://user.itl.net/...er/BatDetector/
http://detector-sens...or-circuit.html
http://integraonline...n/detector.html
http://home.earthlin...TheBatShop.html
http://home.earthlin...ector/SBD2.html
http://www.btinterne...pentops/bat.htm
http://www.goldmine-...sp?number=C6899
http://njsas.org/pro.../sk207_sch.html
http://bertrik.sikken.nl/bat/tjerk.htm

I do have some expeience with bat detectors (and robotics). I've built most or all of the above and given them away. My favorite is the simplest radio-based detector.

Most of these are based on the Popular Electronics design:
http://njsas.org/pro...heterodyne.html

But still, if I had your money, I'd throw mine away!

Thanks for the links, you are the "Bat-Man"!

I decided to purchase based on the "overbooking" of my time as it is. My purchased one has a dual input, with frequencies shown, Mine also goes up to 150 kHz, much higher than the kit ones, although I'm not sure what to expect over 100 kHz?

I "expected it to work flawlessly and be "de-bugged". I'm happy with it. The "robot" will consume most of my "project" time, so I spent the cash...............

[Robot]

boatlesspirate, on Apr 5 2010, 04:12 PM, said:

I picked up a Belfry bat Detector as I was curious if EVP’s were the result ultra-sonic contamination. Although I was disappointed that the Belfry did not de-mux down the ultra-sonic sounds into our hearing range (it clicks away with the sound), like you I found that there was a lot going on that we couldn’t hear. I agree, I use it more for debunking things at this time. I have not captured any EVP’s in concert yet when the Belfry was triggered, but I did have an interesting thing happen on an outdoor daytime investigation. While doing an EVP session, the Belfry started clicking away at the same time my tri-field natural EM did. This was right when we were asking if someone could speak to us or let us know they were there. This went on for about 30 seconds and both meters stopped. I did not pick up anything on my recorder other than the clicking of the Belfry and the buzz of the tri-field. Paranormal? No idea . . . but I have no explanation yet. The jury is still out on this one.

Great input, Thanks!

Hard to say about the Tri-field and Belfry, hopefully they were not "cross-talking" to one another. My bat-listener is very sensitive to static discharge noise.

It might be interesting to "time code" a audio track, a bat listener track, and a inductive amplifier audio track. Mix them together, analyze them and see what commonalities they have.