THE BEIGE BOX

A beige box is an easy way of tapping into phone lines. It is basically an adaptor for connecting a normal phone with a BT plug onto a pair of phone wires.

You will need: one cheap phone, two crocodile clips, some wire and a telephone socket and wallbox. If you use a master (primary) socket your phone will be able to ring; if you just use a secondary (slave) socket, it will never ring. {but see below.}

HOW TO MAKE IT

Solder the crocodile clips onto each end of half a metre of wire. Cut the wire and pass it through a convenient knockout in the socket wallbox, so that the clips are on the outside. Connect one wire to pin 2 of the phone socket, and one to pin 5 of the phone socket. {it is easier if your socket has screw terminals rather than IDC terminals, especially if your wire is stranded.} Screw the socket onto the wallbox and plug in the phone. That's it.

HOW TO USE IT

Clip the clips onto the two wires of a phone line, and dial away. That's all you have to do.

IDEAS FOR IMPROVEMENTS

  1. If you used a secondary socket but later decide you would rather have a primary socket, simply add a 1.8uF 100V capacitor in the position marked C1 on the PCB inside the socket. {1.5uF or 2.2uF will do the job, if you can't get 1.8uF, but it must NOT be an electrolytic capacitor, and it MUST be rated 100V or over.} If you are using a slimline socket without a PCB, the capacitor should be wired between pins 2 and 3.

  2. If you want a line status indicator: get a two-colour LED {the type with two leads, that glows red when the current is in one direction and green in the other} and a 6.8k resistor. Wire these, in series, across the position marked SP1 on the PCB. {don't connect the middle of the series pair to anywhere.} For PCB-less sockets, this is the equivalent of pins 2 and 5, ie the pair connected to the clips. It will indicate the line polarity {red or green} which is not particularly important, and the line status {dim = in use, bright = clear} which is.
Original idea by Jolly Roger, modified by THE KEZ for the UK. disclaimer: this is for informational purposes only. no responsibility is accepted for any consequences of use or misuse of any information contained herein. any material whose source i have not acknowledged is believed to be my own - if it sounds like something you invented, just remember great minds think alike.