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File List | 1993-08-13 | 5.0 KB | 94 lines |
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- Crashed Bulletin Board Automatic Rebooter
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- ┌─────────────────────────────────────────────────────┬──+12vdc
- R1 │ R2 RL1 RL2 R3 │ R4
- ┌──┬───┼──┬─~~~~─┐ ┌─NC─> <─NC─┐ ┌─~~~~─┬──┼───┬──┐
- ┌─~~~~┘ ┌─┴──┴─┐ │ ═────>A C<────═ │ ┌─┴──┴─┐ └~~~~─┐
- │ │ 8 4 │ │ D1 ═─NO─>B D<─NO─═ D3 │ │ 4 8 │ │
- ├───────┤7 3├────)─────>├─┬─) (─┬─┤<─────(────┤3 7├───────┤
- │ │ IC │ │ D2 │ ) ( │ D4 │ │ IC │ │
- ├───────┤6 2├────┤ ┌>├─┘ ) ( └─┤<┐ ├────┤2 6├───────┤
- │ │ 1 5 │ │NO ├─────) ( ────┤ NO│ │ 5 1 │ │
- │ └─┬──┬─┘ S1 │ │ -12vdc │ │ S2 └─┬──┬─┘ │
- │ + C1 │ └┤├┐C2 ┌┘ │ │ │ └┐ C3┌┤├┘ │ C4 + │
- └─┤├──────┴─────┴───┴────┴───────────┴───────────┴────┴───┴─────┴──────┤├─┘
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- A<───┐ C<───┐ NC┌──────> Place in Red or Green wire in
- B<─┐ │ D<─┐ │ ═──────> the telephone lead to the
- │ │ │ │ NO═ answering machine.
- │ │ NC┌───────┐ │ │ R5
- │ │ ═──┐ │ │ │ NC┌─────~~~~~~──────>X To Answering
- │ │ NO═ │ │ │ │ ═──┐ ___ NO ┌─>Y machine motor
- │ └───) │ │ │ │ NO═ │ ═──S1 │ leads.
- │ RL3 ) │ │ │ └───) └──) │
- │ ┌───) │ │ │ RL4 ) ┌──) │
- │ │ ┌──┴──┐ │ │ ┌───) │ ___ NO │
- │ │ │ │ │ │ │ │ │ │ ═──S2 │
- │ │ └──┬──┘ │ │ │ └──) │
- │ │ │ │ │ │ ┌──) D5 │
- │ │ │ │ │ │ └─────>├─────┘
- ┌─┐ │ │ │ │ │ │
- ┌──┤F├──(─┴──────┴────(────(─┴──────────────┐
- ┌─┴─┐└─┘ │ │ │ ┌─────┴──────┐
- ─┤120│ │ │ │ │ 12 vdc ├──>+12 vcd
- ─┤vac│ │ │ │ │power supply├──>-12 vdc
- └─┬─┘ │ │ │ └─────┬──────┘
- └───────┴─────────────┴────┴────────────────┘
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- R1 & R4 - 1 megohm Pot. │ RL1 & RL2 - Mini relays, 5 to 9 volts
- R2 & R3 - 10 kilohm │ 250 to 500 ohms
- R5 - as required * │
- C1 ------ 47 uf │ * Install R5 & D5 if necessary, ratings
- C2 & C3 - .01 uf │ as required to rectify current and limit
- C4 ------ 100 uf │ voltage across S1 & S2 coils
- D1-D4 --- 1N914 diodes │
- S1 & S2 - 5 vdc micro relays│ Set R1 to pull RL1 20 sec.
- (coils in SERIES) │ Set R4 to pull RL2 100 sec.
- F ------- 10 ampere fuse │ NC = normally closed; NO = normally open
- IC ------ 555 Timers (2) Cut up a heavy duty extension cord for leads.
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- All parts are off-the-shelf from Radio Shack.
- Parts layout is not critical. Perforated board and a plastic project box
- make a tidy parts support and enclosure.
- Cyanoacrylate glue will hold the larger parts to the project box.
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- Operation:
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- The computer is connected to the plug which is powered through the
- normally closed contacts of relay RL3.
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- An old answering machine is used as a ring counter. Its telephone
- connection is made to the telephone feed-through of the BBS computer modem.
- It is set to answer on four or more rings (Recommended: announce only mode,
- if possible). The outgoing message tape motor power leads are tapped and
- the taps are lead to points X and Y. Resistor R5 and diode D5 limit the
- voltage across the S1 and S2 coils to their rated levels and rectify AC
- motor current (install only if required). Switches S1 and S2 are the
- normally open contacts of the micro-relays.
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- As long as the BBS answers on the first or second ring, nothing happens
- in the Rebooter.
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- If the BBS fails to answer by the fourth ring, the answering machine starts
- and the tape transport motor voltage closes S1 and S2.
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- Closing S1 and S2 pulls in relays RL1 and RL2, closing normally open
- contacts AB and CD, and holding them for 20 and 100 seconds, respectively.
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- Closing AB pulls in relay RL3, which drops power to the computer power
- plug for 20 seconds, causing a cold reboot.
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- Closing CD pulls in relay RL4 for 100 seconds, which opens the telephone
- connection to the answering machine and also opens the answering machine
- motor lead taps, which prevents a persistent ring from interupting the
- reboot cycle.
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- In practice, the relays trigger each other so rapidly that the calling
- party never detects the action. The calling party hears only an unanswered
- ring, and is not charged with a connection on a toll call.
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- It may be possible to substitute one 556 dual timer chip for the two 555
- chips, or it may not. I know the circuit using to 555 chips works well.
-