Repeater Abuse (continued..)

2/  Moving in closer.  Once a rough area has been defined it’s time to go mobile on foot or in the car.  The best way to do this is using a purpose built direction finder such as the ‘Whistling dipole unit’ (see ARRL handbook, or Ramsey Kits catalogue), or the much more sophisticated Doppler devices (you would probably have to build one of these although I believe that there are a few commercial designs on the market ).  However you can often get pretty close using a small beam and receiver.  When you get close in the signal will be very strong.  If your receiver has an RF gain you can reduce the signal and get in even closer.  If you have an RF sniffer type frequency counter this will allow you to get within a few feet of the source.  These devices act like extremely deaf receivers and will usually only pick up a signal at a few hundred feet maximum (in open space).

Once you’ve found the offender make a note of address, time, date, frequency etc. Check the call book to see if they are in there. Also check out the elctoral role if they are not in the call book. Pass the details onto your local branch of the Radio Investigation Service.  Fixed station offenders are usually fairly easy to track down.  Mobile offenders however, are much more difficult.  You will normally need a very well co-ordinated team to track down a mobile, or if you are on your own, a doppler type DF unit. Other essential items for DFing do of course include a compass and map!