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Phoenix Programmer - This circuit will allow you to place a
phone call on hold and if you wish to have them listen to music while they
are on hold.….
Phone Intercepter 1 - This device connects between the phone
line, an answering machine, and your phones. When a phone call comes
in, the answering machine picks up the call and informs the caller to
enter….(Circuit design added 05/09) [Luhan Monat - Mesa Arizona]
Phone Interceptor 2 - This unit is an upgrade of the previous
phone call interceptor. Instead of using an answering machine to provide
the outgoing message and recording functions, it uses the ISD4004
….(design added 05/09) [Luhan Monat - Mesa Arizona]
Phone Line Box - Creating projects that connect to the phone
line can be a real chore without some device like this. It generates the
48 volts DC for the on-hook condition, the 100 volts AC for the ring
signal, and the 20 milliamperes DC for the off-hook condition.….(Circuit
design added 05/09) [Luhan Monat - Mesa Arizona]
Phone Messager - I always keep one totally self powered phone (the way they
all used to work) in case of a power failure. This device works the same way,
taking all of its power directly from the phone line…. [Luhan Monat - Mesa Arizona]
PIC 16f84 Clock - Can be used to turn off devices after specified time....
PIC 3rd Harmonic Meter - The PIC board detects 3rd harmonic
distortion of AC power line. ….(electronic schematic added 06/09)
PIC Based RS485 Multiplexer - Recently, I had to design a circuit
real quick that transmitted 4 parallel TTL data bits over 350m of twisted
pair cable. I needed to feed in four parallel data bits at one end, and get
4 parallel data bits out the other end, completely transparent to the
transmitting and receiving circuits(added 8/06)
PIC Caller ID - Caller ID circuit displays name and a telephone number of
the person that is calling you. Information is decoded using MT8870 DTMF decoder and
PIC16F628 microchip and is displayed on 2x16 LCD. ….(design added 11/08)
PIC debugging routine reads out binary numbers - 12/07/00 EDN-Design
Ideas.The “burn and learn” method of firmware development excludes an in-circuit
emulator and a serial port.With this method, it is common practice to use spare I/O
pins on a mC as a debugging aid. By strategically placing instructions to set and
clear these I/O pins in the code....PDF contains multiple circuits, scroll to find
this circuit....[Design Idea by Brad Peeters, Theta Engineering Inc, Costa Mesa, CA]
