    





    R~D áOX PHR~A ~S!
    
    r ~ r E L ' ~,S
    ~n the si~iJle-~ t ~:in phor~es I have frequently been
    
    ~bLe to ~et a ~i;1 ~ne by putting in a nickel and giving
    ~he nooLs~viLch a short tap (tLis takes practice) . I-he
    dial ~vontt work, though, so you will have to tap out
    211 to get the operator.
    I ha~e bullt a red box using an oscillator, a telephone
    earpiec~, and an AE phone dial. The shorting contacts
    ~f the dia1 are used to turn on the oscillator when the
    disl is off normal, and the break contacts are used to
    snort out the output of the oscillatcr except during the
    tone pulses. Nickel, dune, and quarter sounds are
    made by dialing 1,2, and 5 respectively. (although
    #6 seems to sonnd better as a quarter)
    On my phone line whenever you dial a toll call
    (including 800 and info), the polarity of the line is
    reversed for about a second. If a diode is wired into the
    line so that it conducts only wLen the polarity is normal,
    the phone will be elechrically hung up wLenever a long
    distance cad is made & can be used like a 'tdial-lockt'
    but this device is foolproof (but only for long distance).
    -H.G. NY-
    
    t4OQ~tLn ~ rA~r6
    
    NO - ALLY-C~oS~”
    ~ c¯~rae~s
    
    i
    
    9v:
    
    ED. NOTE: For those of you who want to make a
    simple and reliable red box, we show a schematic
    of an osc~ll~tor and amplllier and telephone d~l.
    It is basically the same as last montUs red box,
    except that a telephone dial replaces the Dip-flop
    and timer, thus mechanically producing the tones,
    
    All resistors are half watt 10~. Transistor is
    2N2222, SK3020 or Hep 54. 30K trtmmer is used
    to adJust i~equencies to match tbat of a pay phone.
    3lemember, pay phone tones are best heard on
    another phone that has called the pay phone.
    When listening to an acLual pay phone, keep in
    mind that a quarter produces f„ster beeps than
    a nickel or dirne. Adjust the speed of the dial to
    produce accurate nickels or dimes. Ihen simply
    force dial to reburn ~ster for the quarter (it takes
    a littte practice). If you don't know how to adjust
    the speed of the di~ here's how it's done: on the back
    of the dia1 is a governor which looks like a disc brake.
    The semi-circolar brake shoes slow down the d;~
    when not held in tightly by the spring. Tighten the
    spring for faster rli~ re~rn. ~Ihis is tricly on the
    enclosed governors, bot it can be done.
    
    Gi
    
                       _
                   70 OP - P
    
    i~i
    
    _~+ _
    
    ~T~OP)
    ~gur
    
    Our Red Box clrcuit of last month isn't perfect, and
    we've got a few irnprovements. First, change the v~lue
    of the 2. 2K flip~Dop resistors to lOK ohms. This wil1
    cut down your battery drain to less tban 4 mil~i~mps.
    
    Secondly, if you're getting strange extra pulses when
    you continue holding a button down, try putting a 25 mfd.
    capacitor right across the battery.
    
    Einally, if you experience incomplete turn-on or turn-
    off of the tones, change the 22K timer output resistor to
    47K.
    
    If you want to build a red box but don't know how, \]PL
    will publish next month instructions for recordiny the
    tones perfectly on a cassette tape recorder. Any inexpen-
    sive unit will work, but it's easiest to use a cassette with
    manual recording lovel controls.
    
    In August of 1970 I called up irdormat;on and got a mam
    on the line. IIe said he was inforrn~ tion and alber a wh;1e
    I got him to tell me how he got on the~ line.
    
    He told me all you have to do is call 411, wait for the
    assistant to h~g Up, and just hold on to the line. Well,
    I did iMi~ and ~ my s~r~e ~o~e wo~d come on ~e

    





    line ashing for information. Ihe line wollld be compiete-
    ly silent between callers and I wouldn~t have to hang up.
    There was just a click and I knew someone else was
    on the line. I did this for 3 days. After that, since
    1970 I haven't been able to do it. If anyone knows of
    this happening, I hope they can tell me how lt can
    be done now.
    
    Also, during the same time period, I used ~ dial
    830-7Z67 and the line was dead. Once in a while I
    would hear two peopie then ~k to each ot~er. Any
    more numbers that do tbat anymore?
    
    -S. ~KT Il, N. Y. -
    
    :~1
    
    