Olive Box Plans
This is a relatively new box, and all it basically does
is serve as a phone ringer. You have two choices for
ringers, a piezoelectric transducer (ringer), or a standard
8 ohm speaker. The speaker has a more pleasant tone to it,
but either will do fine. This circuit can also be used in
conjunction with a rust box to control an external something
or other when the phone rings. Just connect the 8 ohm
speaker output to the inputs on the rust box, and control
the pot to tune it to light the light (which can be replaced
by a relay for external controlling) when the phone rings.
______________
| | NC --|-- 5 4 --|-----/X/X/------->G
| | / R2
G<----)|----|-- --|---------- - 2 3 6 7 | --|-- --- -- C3 NC U1 -------|--> TO RINGER
| |
----|-- 8 1 --|--
| |______________| |
| ---/X/X/----|(----- L1
| R1 C1
------------------------------------------ L2
a. Main ringer TTL circuit
FROM PIN 2ive:G
P1
f b. Peizoelectric transducer
__ /|
FROM PIN 2 ||||||||<.--- TRANSDUCER
Parts List
- U1 - Texas Instruments TCM1506
- T1 - 4000:8 ohm audio transfomer
- S1 - 8 ohm speaker
- R1 - 2.2k resistor
- R2 - External variable resistor; adjusts timing frequency
- C1 - .47uF capacitor
- C2 - .1uF capacitor
- C3 - 10uF capacitor
- L1 - Tip
- L2 - Ring
L1 and L2 are the phone line.
Shift Rate:
This is the formula for determining the shift rate:
f 1 1
SR = --------------------- = ------------ = 6.25 Hz
(DSR(1/f1)+DSR(1/f2)) 128 128
---- + ----
1714 1500
DSR = Shift Devider Rate ratio = 128
f1 = High Output Frequency = 1714
f2 = Low Output Frequency = 1500