99 lines
4.0 KiB
Plaintext
99 lines
4.0 KiB
Plaintext
-------------------------------------- --------------------------------------
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- The Conference Box - - By: Madd Max -
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-------------------------------------- --------------------------------------
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What is a Conference Box?
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After hooking a conference box on your line you can talk on two lines at
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the same time. Therefore, if you already have 3-way on both lines, you could
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talk to 4 people at the same time (5-Way...). This version works (Unlike that
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box you can 'PICK UP' at Radio Shack...).
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What do I need?
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Item Description
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---- -----------
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C1 10-uF, 50-volt electrolytic capacitor
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C2 Another 10-uF, 50,volt electrolytic capacitor
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C3 10-uF, 15-volt tantalum capacitor
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R1 10K, 1/4 watt, 10% composition resistor
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R2 100-ohm, 1/4 watt, 10% composition resistor
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Q1 2N3904 npn silicon transistor
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S1 Dpst toggle switch
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S2 Another Dpst toggle switch
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T0 Telephone coupling transformer, Microtran T2110 or equivalent
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Some wire or a circuit board (Design your own)
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Some electronic equipment
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A box
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A little patience
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Notes:
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The 'Item' is used to indicate where it goes in the diagram. You can use
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any transformer which is rated at about 900 ohms both primary and secondary,
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over the frequency range of about 300 to 3000 Hz.
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How does everything go together?
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+ / C1 C2 / +
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----,----* *------*------$-----@ @---------$----*----*----* *----------,-
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Line 1 ' ! + @ @ + ! ! ' Line 2
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' ! @ @ ! R1# '
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' ! @ @ ! ! '
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S1 ! @ @ \: ! S2
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' Telephone @T0@ Q1 :--* '
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' Set @ @ /: ! '
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' ! @ @ ! !+ '
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' ! @ @ R2# $C3 '
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/ ! @ @ ! ! /
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---------* *------*------------@ @--------------*----*---* *-------------
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What did all that mean?
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Symbol Meaning
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------ -------
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- Horizontal Wire
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! Vertical Wire
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* Point where wire splits, separates, merges, etc.
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/
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* *
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'
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'
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' A Dpst toggle switch
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'
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'
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/
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* *
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$ Capacitor
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# Resistor
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@ To the Transformer
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+ Positive end (of line or capacitor)
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- Negative end
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\:
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:-- Transistor
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/:
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How do I use it?
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Pick up the telephone set and flip the first switch on. You should get a
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dial tone. Dial someone and tell them to hang on. Flip the second switch and
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you should get another dial tone. Dial another number. After they answer, you
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should be able to talk to both of them and they should be able to talk to one
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another. If you have 3-Way on one (or both lines) you can flip the switch
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corresponding to that line on and off (RAPIDLY) to switch the 3-Way.
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NOTE: Because you went to all the trouble of making this with a transformer, it
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should sound PERFECT!
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