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divertor.txt
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1994-03-06
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6KB
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121 lines
Diverter 1992. An alternative to the DARK BOX.
Design: Mavicon M.D., The Ear, and 2 that shall remain
nameless.
Plans: Mavicon M.D.
Diverter Plans
Parts List:
Everything can be obtained at your local Radio-Shack. As much as
i hate that store, they are convenient...
RLY1 DPDT relay
T1 1:1 audio transformer
D1 1N914 or similar diode
D2 large LED
LMP1 neon lamp
R1 10 k
R2 photocell
R3 22 k
R4 47 k
Q1 2N2222, 2N3904, 2N4401, most any other NPN switching
transistor
1 nine volt battery. The negative terminal goes to ground on the
schematic. Positive terminal to +9 volts.
Assembly:
The best way to assemble the design is to grab one of those small
copper lined perfboards from Radio-Shack. They are nice to work
on, and can easily be trimmed down to a minimum size once
everything is soldered in. The process is the same as any other.
Solder all the parts in per the schematic. The photocell must be
in a position so that the light from the neon lamp(LMP1) and the
LED(D2) both shine on it. All the polarity must be observed.
Whichever direction you put the led in, you must remember (color
code your wires, green is positive, red is negative, yellow is
positive, black is negative) the negative side of the line must
go to its negative side. The same goes for the transformer. the
positive side of each line has to be connected to the correct
pair on the transformer. On the Radio-Shack transformers, put
positive of both lines on the Red and Black pairs, The negative
on Yellow and White. Our prototypes have reached less that 1" x
1" in size.
NOTE: The entire thing MUST be wrapped in black tape. IT must be light tight
or you will have a relay that turns on with the sunrise.
Theory of Operation:
The diverter works on some basic electronic principals. Step by
step. The phone rings. The neon lamp is activated by the high
voltage(88 p-p) ac and flashes. This light shines on the
photocell, decreasing its resistance. When this happens, the
positive voltage flowing through the photocell and the 10k
resistor exceed the breakdown voltage of the base of the
transistor and switches that transistor on. Once the transistor
is on, current flows freely from emitter to collector, energizing
the relay. The relay's two sets of switches connect both lines
to the 1:1 audio transformer, effectively taking both lines off
the hook and coupling any audio signals from either line to the
other one. Once this happens, current is now flowing through the
transformer,relay,led loop. This current lights the led and that
light shines on the photocell. This is what keeps the device
latched. The light from the led keeps the photocell resistance
low enough to keep the transistor on. Now, you make you call and
get on with your business. You hang up. Now, the local CO keeps
current flowing through the indial line for about 5 seconds, at
which point it drops down for a second or so and then goes back
up. This is the signal the device uses to determine when you've
hung up. When the current drops down, there is no light, and the
photocell resistance raises enough to turn the transistor off and
delatch the entire system.
Applications:
The applications are relatively obvious. Hook it up to two
unused lines and make free calls. Hook it up to two payphones,
and red box calls. The only thing to watch out for is ringing.
If you hook it up to a residential line for the indial a small
(maybe 1/8) of a ring occurs when you call, tipping off people
inside the house.
|-------------------------------------
| | o +9V
| L1+ T1 | |
| o-------wwwww----------| | |
| | | |
| L1- | | |
| o-------------| | | o--------|
| | | | | |
| | | | | |
| | | | | |
| L2- | |---l----------l---------l--| _____
o-------\ LMP1 | | | \| | | w | /^\ D1
R4 47k * | | | | |\ | w | /---\
--\/\/--/ | | | | | | | w | |
| | |-l----------l-----------l--| |
| | | RY1 | | |
o L2+ |------| | | |
| | o---------
| | |
| | ----|
| D2 | /
| |\ | T1 | /
|----------| >|-----wwwwww---------- /
|/ | 000
|--------- 000 Q1
| 000
oooo | \
o o 10k | \
o-------o-/\/\/o------------/\/\/---| \
+9V o o R2 \ R1 |
oooo / 22k -----
\ R3 ---
| -
|
-----
---
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