I recently manage to get hold of a RF scanner. I use it to scan the living room of an apartment. The scanner beeps in mid air when a human body object is near to the scanner. Can some one tells me what can possible to the cause?
Is it possible for the reflected frequencies from a motion detector to trigger the beeping sound?
Motion detectors use Infrared, Microwave or ultrasonic
RF is for RADIO FREQUENCIES so if it is going off then you have a radio transmitter somewhere nearby. Sounds like you have a very low power transmitter (often found in high-tech covert surveillance equipment) that is very hard to detect. Sometimes, however, the human body can act almost like an antenna (ever had your radio station go in and out based upon where you were standing in the room?) and you lucked upon the perfect position from which to detect your transmitter.
Maybe you can use that to help narrow down where it is...
"Human body object"... HBO... "New show every day." :-)
Seriously... An RF scanner is liable to pick up any RF (depending on the quality of the unit). What's the make and model #? Is the security system in the apartment a wireless job? Before we can answer your question, we need some more info.
I use a normal RF scanner call pro hunter. It has a wide RF range. To my knowledge there is no security system installed in the apartment. I tried using the scanner in other parts of the apartment it doesn't beep. Most of the beeping is in the living room. The strange thing is it beeps in mid air at a distant away from the floor and ceiling. If you move away to one side, it stops beeping. Please help me to understand.
Without knowing all the specs for this particular scanner I can't comment. If you're looking for "wireless spy cameras" (which this unit is supposedly designed to detect), then I would suggest you start by looking for objects in the area where you're getting the signal that may be big enough to conceal a camera or microphone. These days you can hide cameras inside smoke alarms, light fixtures, etc. Please be careful when removing any ceiling fixture that may be connected to mains power. If there's nothing discernable then you're probably getting a false reading from someone's wireless internet router, or perhaps one of your neighbours is running powerline equipment like X-10 (as an example). These days, we're all "drowning" in RF signals. They're everywhere. You could also have a defective unit.
On a side note, I find I'm changing my tin foil hat a lot more frequently these days, which also affords me the opportunity of trying out different designs to tune out different influences. ;-)
What you don't know, or haven't considered is that there are radio frequencies around us, every where we go. Look up "Beat Frequencies" It's basicly the same process that is used in hetrodying radio receivers where they take a received broadcasted radio frequency, join it with a known frequency which is produced by the radio circutry and when the two are joined, it results in a third frequency. Basiclly, that third frequency (beat frequency) which is produced, is the sound you hear coming out of your radio.
Now, if you apply that same process to all of the radio frequencies that are around us every day, there are going to be random "hot spots" where multiple frequencies "beat" together which produce first, second, third etc, etc, etc, harmonics which you can pick up very easily with a broad band receiver. If your RF detector had a hetrodying circuitry and an amplifier in it, you'd actually be able to hear what was being received, if some of the components of the signal where from commercial radio stations. Sometimes you can hear military transmissions, ham radio, business information data transmissions ( such as OTB). Sometimes you can hear radio stations from the other side of the world. AM radio transmissions bounce off of the ionosphere and can travel great distances. Actually your receiver is almost the same as one of those world wide trans-oceanic radios that you can buy, however they are broken down into tunable frequency "bands". Your receiver likely just receives all frequencies in the radio spectrum simultaniously.
DETECTING DISTANCE: Wireless Camera: 1.2 GHz --- about 3 M; 2.4 GHz --- about 70 cm Cellular phone: about 1 M Applications: Detect hidden camera in hotel, motel and club house. Detect hidden camera in shopping mall toilet, school toilet, locker room and fitting booth, etc. Prevent video body bugs to protect office, factory and personal privacy. SPECIFICATIONS: Size: L 79 x W 28 x T 15 mm Weight: about 26g (included battery) Power: 6V DC (CR2032 lithium battery x2) Detecting frequency: 50 MHz ` 3.0 GHz Warning mode: Sound and LED display
tenfoil the window to that room and see if it stops. Had a problem kinda like that and it was from stray Microwave communications tower links which was bouncing into the apt we were checking..
on another note we had a stray signal in the office once that was coming from the FAX machine, seems the heater to the thermo paper had a hair line crack that was putting out microwaves just right for the detector..
Ok, so it's a narrow band receiver.
Same problem. Same reason. Beat frequencies, harmonics.