Radio Direction Finding, Bird Dog 360

Bird Dog 360 Receiver

A new toy of mine has been the Audio Intelligence Devices, Bird dog 360 Receiver. This is an old school, professional grade direction finding receiver made in the late 1980's. These were commonly used by private detectives and police departments to track suspects while driving vehicles. They came with very specific transmitter frequencies and a magnet mount transmitted that needed to be placed on the vehicle. The receiver consists of two main components.

The main components of the receiver are the receiver box and the display unit. The receiver box allows for the reception of up to 6 transmitters at a time and can look for pulsed RF signals as well as audible modulated signals. Continuous Wave (CW) and voice settings allow you to listen to more than just the transmitters included in the kit. Line lever outputs are included for headphones and connection of a tape or digital recorder. A large speaker is on the face of the receiver, and puts out some loud audio. A ribbon cable with locking connectors sends received data to a display unit that can be up to three feet away from the receiver box.

The display unit has the common circle of LED's and a center display that gives a numeric value to the bearing of the received signal. Signal strength and indications for movement alarms can be shown as well. The entire display is red and can be dimmed to a point where no light is output. This is perfect for those discrete moments when everything needs to go dark. These would have been used in a van or truck with blacked out windows or curtains most of the time, but you never know when you may need this feature. These two boxes connect to four antennas, and receive signals from a small magnet mount transmitter.

The antenna array is also magnet mounted to the roof and must be in a specific square orientation. Each antenna is the same length and uses the Doppler effect to determine bearing and distance. What this means is that each antenna receives a signal and each signal is compared. The one closest to the transmitter determines the bearing. Then the other three are used to determine strength. electrically this requires the antennas to be separate from each other physically, but with the same length of cable, and insertion loss. With four antennas, with the same cable, same resistance and other electrical factors, it is easy for an electronic circuit to determine direction and signal strength.

Then it is a matter of driving around and getting used to the unit. Neither the receiver box or display nit has any way to connect it to the dash. No suction cups, Velcro, or mounting brackets are included. These really look like they would be mounted to a shelf or desktop. Small rubber feet are on the bottom of both units. The display box being so light that the ribbon cable forces it to go where the cable folds push it. I use this system with the receiver seat belted to the passenger seat and the display wedged between my windshield and dash. The red display and background lighting match perfectly with a Pontiac or BMW back light scheme.

In 2015, many people may wonder why a hardware direction finding kit is useful. Software and computers have replaced a great deal of test equipment and radio gear. Well in the case of direction finding, even the software based systems require the use of hardware antennas and some form of interface box. The  fact that a computer is not required could be seen as an advantage or a fault. Computer based receivers could log the data better, but would require software updates, a computer to be booted and connected, and Microsoft licenses to be updated on occasion. For stand alone units, they just work, and do not need updates to work. Their is also no possibility of malicious code or corrupt software causing damage to the equipment. For the amateur user, the only other real option is the Ramsey electronics kits. these are small plastic kits that are for hobbyist use, they are not as rugged and do not appear to hold up well with permanent installation.

For those with the need to find and range a specific radio signal, look to used commercial gear to fill this need. As a better alternative to the hobbyist kits, this type of receiver can be found on auction sites and used radio locations. Seek out county auctions, police and fire department sales. Often times the hardware is older, but fully functional. It may only lack a manual or a cable. I have had great luck finding very well made hardware that has minimal usage time for cents on the dollar this way. You can build up your arsenal of radio gear quickly and it will last longer in the field. Good luck on the fox hunt, happy hunting.

Please Try It Our Way First

Try It Our Way First

Everbuy something and proceed to break it by not reading the instructions? Sure you have, most guys have done this at some point in their life. So would you do this to something sophisticated like a business telephone system? How about a telephone system used got 9-1-1 call taking? Some companies do this.

When I bought a sophisticated piece of electronic hardware, with many subsystems, it came with a note to "Before you do it your way, Please Try it Our Way". This company had obviously had too many end users try it their own way first. I have seen this with many telephone and dispatch vendors for 9-1-1 equipment. Feel safe? Have you ever needed to call 9-1-1? Wouldn't it be better if you knew that smart and competent people were involved?

The people who install and maintain many 9-1-1 dispatch and telephony systems, do not read the manual first. Sometimes they are not even trained on the gear they install. Other times, they lack the basic installation and test equipment to do their job. This may not be the employees fault, perhaps the company only buys a few pieces of equipment. For phone systems, and telephone service technicians, a common piece of gear is the buttset. Tone wands helps trace wires. Multimeters show electrical activity. These should be in every technicians toolbox. However,without knowledge, or reading the manual, these are all worthless.

In this litigous age we live in, even items that should not need instructions come with them. So when you purchase complex hardware, why not read the manual? Do you really want to look like a fool in public? Do your part and read the instructions. Knowledge is power, and knowledge is becoming harder to come by. For you sake and for those that may rely on your work, read the manual and do it by the book. This will take you far in life, and may safe your job some day, or even someones life. That life may actually be your own. Imagine if I decided to not worry about instructions one day. What if I did this with a Mk12 thermonuclear warhead? Before you do it your way, please try it our way first!

Who Watches the Watchers

Who Watches the Watchers?

Ever think about who watches the watchers? Many peope say that we do not need to keep tabs on the overseers, our government, or military. Sure there is supposed to be Senate oversight, the Bill of Rights, and the Constitution. Well in the real world, we, the citizens watch the watchers.

The American people need to watch their government. If you do not like something, do something. If someone is hiding things on their own servers, back it up on your own server. Much of the data that moves around the world, goes over satellite, the internet, or telephone lines. This makes it pretty easy for us to keep an eye one government officials. Just as ISIS used social media to keep tabs on military personnel, or steals information and service records, this can be used by pretty much anyone in society.

Obviously, if you are the type that has that blinking 12:00 on your VCR, this may not be your area of expertise. But for those that can, a lot of this information is free for the taking. It's not just social media, much of the worlds traffic is transferred with little encryption or security measures in place. Get yourself some equipment, education and practice with it. You may be amazed at what is out there. Most of society has smart phones now, this is an easy way to watch the watchers.

The news has shown how a camera in the hands of a citizen can keep those that would harm you at a distance. Cameras and information are powerful tools. We have the power to monitor and keep our leader in their place. Better yet, vote them out of office. Stop listening to their scare tactics. Take ownership of your leaders, and watch them closely. If they feign ignorance, but the proof is out there, post it for all to see. Here is one method I use to keep tabs on some of the radio waves.

Shown here is a small listeing station, monitoring UHF satcom transmissions. Trivec satcom antennas and high end data capable radios allow for the logging of radio traffic all over the world. Forums online show how to set up your monitoring station, what works equipment wise, and how to get everything tuned just right. Just remember, we watch the watchers. We hold the power.