133 lines
8.0 KiB
Plaintext
133 lines
8.0 KiB
Plaintext
AM LIGHTWAVE TRANSMITTER AND RECEIVER BY JOE SCHARF
|
||
-------------------------------------------------------------------------------
|
||
SCHEMATIC 1 [TRANSMITTER]
|
||
-------------------------------------------------------------------------------
|
||
|
||
|
||
MIC* C1
|
||
() + .1 uF
|
||
|---------(OO)-----|(--------| +9V
|
||
| () | ^
|
||
| R3 R4 | /|\
|
||
| 5.6K 5.6K | |
|
||
*---/\/\/\-------*---/\/\/\--|-------*-------*------|
|
||
| | | | | |
|
||
| | >R1 | | |
|
||
| | |---->>>50K | >R5 >R8
|
||
| __|3___|2_ >VAR | >1K >220
|
||
| \ + - / |RESIST | > >
|
||
| \OP AMP/-----|-------- | |
|
||
*----------------\741 /7 | | | **
|
||
| 4 \ / >R2 | C/NPN Q1
|
||
| \/ >1M |---------B| TRANSISTOR
|
||
| |6 > | | E\ 2N2222
|
||
| | | C2 | | |
|
||
| | | + 10 uF | >R6 |
|
||
| ----------*---|(-----*-->>>50K |
|
||
| >VAR |
|
||
| |RESIST| LENS
|
||
| | __|___*** ^
|
||
| | \LED / (|)
|
||
| | \ / ( | )
|
||
| R7> \/ (|)
|
||
| 1K> -----|---- \/
|
||
| > | LENS
|
||
| | | OPT.
|
||
| | |
|
||
| | |
|
||
|--------------------------------------------*-------|
|
||
|
|
||
|
|
||
--------
|
||
----
|
||
--
|
||
_______________________________________________________________________________
|
||
|
||
R1-GAIN CONTROL
|
||
R6-LED BIAS CONTROL ADJUST R6 FOR BEST SOUND QUALITY
|
||
R8-LIMITS CURRENT APPLIED TO LED
|
||
|
||
* - MIC- USE CRYSTAL MICROPHONE OR ELECTRET UNIT (CONNECT RED LEAD TO 9V)
|
||
** - TRANSISTOR - USE A 2N2222 NPN TRANSISTOR.
|
||
*** - LED - USE A HIGH-BRIGHTNESS RED OR HIGH POWERED INFRARED LED FOR BEST
|
||
RESULTS
|
||
_______________________________________________________________________________
|
||
|
||
THE 741 AMPLIFIES VOICE SIGNALS FROM THE MICROPHONE AND COUPLES THEM THROUGH C2
|
||
TO MODULATOR TRANSISTOR Q1. FOR A FREE-SPACE RANGE OF UP TO 1000 FEET
|
||
(AT NIGHT), USE A LENS TO COLLIMATE THE LED BEAM OR USE THIS CIRCUIT AS
|
||
AN OPTICAL FIBER TRANSMITTER.
|
||
_______________________________________________________________________________
|
||
|
||
SCHEMATIC 2 --- AM LIGHTWAVE RECEIVER
|
||
_______________________________________________________________________________
|
||
|
||
|-----------------------------------------|
|
||
| |
|
||
| |
|
||
| |
|
||
| |
|
||
>R1 |
|
||
>100K |
|
||
> |
|
||
LENS | C1 .1uF |
|
||
^ *----|(---------*-------| |
|
||
(|) C| | | |
|
||
( | ) /Q1 | | | +9V
|
||
( | ) B|PHOTOTRANSISTOR | | | ^
|
||
(|) E\ |-----| | | | /|\
|
||
\/ | | __|3_|2_ | | |
|
||
LENS | | 4\ + - /7 | | |
|
||
*-------*----\ 741/------|-----------------*---------*
|
||
| \ / | | |
|
||
| \/6 | | |
|
||
| | >R2 | ------ C2
|
||
| | >100K | ^^ .1 uF
|
||
| | > | ^ |^
|
||
| | | | |
|
||
| |--------* | |
|
||
| | | --------
|
||
| | | ----
|
||
| | 3|\ | -
|
||
| | |------|+\|6
|
||
| | | |* \--------------|
|
||
| R3< | | /5 C3 | +
|
||
| 10K<<------| |----|-/| 100uF -----
|
||
| VAR< | 2|/4| ^
|
||
| RESIST| | | |
|
||
| | | | 8 OHM|---/|
|
||
| | | | SPEAKER| ||
|
||
| | | | |---\|
|
||
| | | | |
|
||
|------------------------*---------*-------*--------------|
|
||
|
|
||
|
|
||
----------
|
||
------
|
||
--
|
||
_______________________________________________________________________________
|
||
|
||
R2-GAIN CONTROL
|
||
R3-VOLUME CONTROL
|
||
C2-PREVENTS OSCILLATION KEEP LEADS TO BATTERY SHORT.
|
||
|
||
* --- OP AMP --- THIS MAY NOT LOOK LIKE AN OP-AMP BUT IT IS (VERY HARD TO
|
||
DRAW THEM ON THE COMPUTER. USE A 386 OP AMP FOR THIS ONE
|
||
_______________________________________________________________________________
|
||
|
||
THIS RECEIVER WORKS BEST IN SUBDUED LIGHT OR AT NIGHT WHEN USED FOR
|
||
FREE-SPACE COMMUNICATIONS ALWAYS PLACE A SHIELD OVER THE DETECTOR IF SUNLIGHT
|
||
OR BRIGHT ARTIFICIAL LIGHT IS PRESENT. AN INFRARED FILTER SHOULD BE USED
|
||
FOR BEST RESULTS (DEVELOPED COLOR FILM WORKS WELL) UNLESS THE TRANSMITER
|
||
LED EMITS VISIBLE LIGHT.
|
||
|
||
CAUTION : THIS CIRCUIT CAN PRODUCE LOUD SOUNDS. DO NOT PLACE SPEAKER CLOSE
|
||
TO YOUR EAR.
|
||
_______________________________________________________________________________
|
||
|
||
FEEL FREE TO PASS THIS CIRCUIT AROUND AND IF YOU HAVE ANY QUESTIONS OR
|
||
PROBLEMS YOU CAN CONTACT ME ON CHUCKS PLACE (304)-776-7078 BY LEAVING E-MAIL
|
||
TO: JOE SCHARF
|
||
_______________________________________________________________________________
|
||
|
||
|