ÍODEM ÎOISE ËILLER
     ------------------


×ITH  SOME BASIC TOOLS INCLUDING A SOLDERING IRON, AND FOUR OR FIVE 
COMPONENTS FROM ÒADIO ÓHACK, YOU SHOULD BE ABLE TO CUT THE NOISE/GARBAGE 
THAT APPEARS ON YOUR COMPUTER'S SCREEN.

É STARTED THIS PROJECT OUT OF FRUSTRATION AT USING A ÕÓ ÒOBOTICS 2400 BAUD
MODEM AND GETTING A FARE AMOUNT OF JUNK WHEN CONNECTING AT THAT SPEED. 
ËNOWING THAT CAPACITORS MAKE GOOD NOISE FILTERS, É THREW THIS TOGETHER.

ÔHIS IS VERY EASY TO BUILD, HOWEVER CONDITIONS MAY BE DIFFERENT DUE TO MODEM
TYPE, AMOUNT OF LINE NOISE, OLD OR NEW SWITCHING EQUIPMENT (ÔELCO'S),
AND ON AND ON. ÓO IT MAY NOT WORK AS WELL FOR YOU IN EVERY CASE. ÉF IT DOES
WORK, OR IF YOU'VE MANAGED TO TWEAK IT TO YOUR COMPUTER/MODEM SETUP É'D LIKE
TO HEAR FROM YOU.

É'D ALSO APPRECIATE ANY OF YOU ELECTRONIC WIZARDS OUT THERE WANTING TO OFFER
ANY IMPROVEMENTS. ÌET'S MAKE THIS WORK FOR EVERYONE!

ÐLEASE READ THIS ENTIRE TEXT AND SEE IF YOU UNDERSTAND IT BEFORE YOU BEGIN.

ÏË, WHAT YOU'LL NEED FROM ÒADIO ÓHACK:

1 #279-374 ÍODULAR LINE CORD IF YOU DON'T ALREADY HAVE ONE. ÙOU WON'T NEED 
           ONE IF YOUR PHONE HAS A MODULAR PLUG IN ITS BASE. $4.95

1 #279-420 ÍODULAR SURFACE MOUNT JACK (4 OR 6 CONDUCTOR) $4.49

1 #271-1720 ÐOTENTIOMETER. ÔHIS IS A 5K AUDIO TAPER VARIABLE RESISTOR. $1.09

1 #272-1055 ÃAPACITOR. ÁNY NON-POLARIZED 1.0 TO 1.5 UF CAP SHOULD DO. ÐAPER,
            ÍYLAR, OR METAL FILM CAPS SHOULD BE USED, ALTHOUGH #272-996 MAY 
            WORK AS WELL. (272-996 IS A NON-POLARIZED ELECTROLYTIC CAP) $.79

1 100 OHM RESISTOR - QUARTER OR HALF WATT. $.19

1 #279-357 Ù-TYPE OR DUPLEX MODULAR CONNECTOR. ÄON'T BUY THIS UNTIL YOU'VE
           READ THE SECTION ON CONNECTING THE ÎOISE ËILLER BELOW. (Á, Â,OR 
           Ã) $4.95

ÆIRST OFF, OPEN THE MODULAR BLOCK. ÙOU NORMALLY JUST PRY THEM OPEN WITH A
SCREWDRIVER. ÉNSIDE YOU'LL FIND UP TO 6 WIRES. ÖERY CAREFULLY CUT OUT ALL 
BUT THE GREEN AND RED WIRES. ÔHE ONES YOU'LL BE REMOVING SHOULD BE BLACK, 
YELLOW, WHITE, AND BLUE. ÔHESE WIRES WON'T BE NEEDED AND MAY BE IN THE WAY. 
ÓO CUT THEM AS CLOSE TO WHERE THEY ENTER THE PLUG AS POSSIBLE. ÔHE OTHER 
END OF THESE WIRES HAVE A SPADE LUG CONNECTOR THAT IS SCREWED INTO THE 
PLASTIC. ÕNSCREW AND REMOVE THAT END OF THE WIRES AS WELL. ÎOW, YOU SHOULD 
HAVE TWO WIRES LEFT. ÇREEN AND RED. ÓOLDER ONE END OF THE CAPACITOR TO THE 
GREEN WIRE. ÓOLDER THE OTHER END OF THE CAPACITOR TO THE CENTER LUG OF THE 
POTENTIOMETER (THERE ARE THREE LUGS ON THIS CRITTER). ÓOLDER ONE END OF THE 
RESISTOR TO THE RED WIRE. ÙOU MAY WANT TO SHORTEN THE LEADS OF THE RESISTOR 
FIRST. ÓOLDER THE OTHER END OF THE RESISTOR TO EITHER ONE OF THE REMAINING 
OUTSIDE LUGS OF THE POTENTIOMETER. ÄOESN'T MATTER WHICH. ÎOW TO WRAP IT UP, 
MAKE A HOLE IN THE LID OF THE MOD BLOCK TO STICK THE SHAFT OF THE 
POTENTIOMETER THROUGH. ÄON'T MAKE THIS HOLE DEAD CENTER AS THE OTHER PARTS 
MAY NOT FIT INTO THE BODY OF THE MOD BLOCK IF YOU DO. ÓEE HOW THINGS WILL 
FIT IN ORDER TO FIND WHERE THE HOLE WILL GO. ×ELL, NOW THAT YOU'VE GOT IT 
BUILT YOU'LL NEED TO TEST IT. ÆIRST TWIST THE SHAFT ON THE POTENTIOMETER 
UNTIL IT STOPS. ÙOU WON'T KNOW WHICH WAY TO TURN IT UNTIL LATER. ÉT DOESN'T 
MATTER WHICH WAY NOW. ÙOU ALSO NEED TO DETERMINE WHERE TO PLUG THE ÎOISE 
ËILLER ONTO THE TELEPHONE LINE. ÉT CAN BE DONE BY ONE OF SEVERAL WAYS:

Á. ÉF YOUR MODEM HAS TWO MODULAR PLUGS IN BACK, CONNECT THE ÎOISE ËILLER 
   INTO ONE OF THEM USING A LINE CORD. (A LINE CORD IS A STRAIGHT CORD THAT 
   CONNECTS A PHONE TO THE WALL OUTLET. ÕSUALLY SILVER IN COLOR)

Â. ÉF YOUR PHONE IS MODULAR, YOU CAN UNPLUG THE CORD FROM THE BACK OF IT 
   AFTER YOU'RE ON-LINE AND PLUG THE CORD INTO THE ÎOISE ËILLER.

Ã. ÙOU MAY HAVE TO BUY A Ù-TYPE MODULAR ADAPTOR. ÐLUG THE ADAPTOR INTO A 
WALL OUTLET, PLUG THE MODEM INTO ONE SIDE AND THE ÎOISE ËILLER INTO THE 
OTHER. ÃALL A ÂÂÓ THAT HAS KNOWN NOISE PROBLEMS. ÁFTER YOU'VE CONNECTED 
AND GARBAGE BEGINS TO APPEAR, PLUG THE ÎOISE ËILLER INTO THE PHONE LINE AS 
DESCRIBED ABOVE. ÉF YOU HAVE TURNED THE SHAFT ON THE POTENTIOMETER THE 
WRONG WAY YOU'LL FIND OUT NOW. ÙOU MAY GET A LOT OF GARBAGE OR EVEN 
DISCONNECTED. ÉF THIS HAPPENS, TURN THE SHAFT THE OTHER WAY UNTIL IT STOPS 
AND TRY AGAIN. ÉF YOU DON'T NOTICE MUCH DIFFERENCE WHEN YOU PLUG THE ÎOISE 
ËILLER IN, THAT MAY BE A GOOD SIGN. ÔYPE IN A FEW COMMANDS AND LOOK FOR 
GARBAGE CHARACTERS ON THE SCREEN. ÉF THERE STILL IS, TURN THE SHAFT SLOWLY 
UNTIL MOST OF IT IS GONE. ÉF NOTHING SEEMS TO HAPPEN AT ALL, TURN THE SHAFT 
SLOWLY FROM ONE SIDE TO THE OTHER. ÙOU SHOULD GET PLENTY OF GARBAGE OR 
DISCONNECTED AT SOME POINT. ÉF YOU DON'T, REREAD THIS MESSAGE TO MAKE SURE 
YOU'VE CONNECTED IT RIGHT.



***ÅÎÄ ÏÆ ÏÒÉÇÉÎÁÌ ÆÉÌÅ***

ÁÄÄÉÔÉÏÎ ÔÏ ÏÒÉÇÉÎÁÌ ÆÉÌÅ - 2/29/88 - ÍIKE ÍCÃAULEY - 

ÆIRST, A PERSONAL RECOMMENDATION. ¤ÔÈÉÓ ×ÏÒËÓ!!!¤  É HAVE BEEN PLAGUED WITH
NOISE AT 2400 FOR SOME TIME. É WENT ROUND AND ROUND WITH ÍA ÂELL ON IT, AND
AFTER THEY SENT OUT SEVERAL "REPAIR PERSONS" WHO WERE, TO BE KIND, OF LIMITED
HELP IN THE MATTER, É THREW IN THE TOWEL. É SAW THIS FILE ON A BOARD UP EAST
A FEW DAYS AGO, AND THOUGHT É'D BITE. ÔHREW THE GISMO TOGETHER IN ABOUT 10
MINUTES, TOOK ANOTHER FIVE TO ADJUST THE POT FOR BEST RESULTS ON MY WORST
CONNECTION, AND GUESS WHAT? ÎO MORE WORST CONNECTION! Á FEW POINTERS:

1) ÔHE POT NEED NOT BE EITHER 5Ë OR AUDIO TAPER. É USED A 10Ë 15 TURN TRIM POT.
   ÓUGGEST YOU USE WHAT IS HANDY.
2) É USED 2ÍÆÄ'S OF CAPACITANCE (TWO 1ÍÆÄ'S IN PARALLEL) ÔWO Ò.Ó. P/N 272-1055
   WORK FINE. ÒEMEMBER THAT ABOUT 90 ÖOLTS WILL APPEAR ACROSS RED & GREEN AT
   RING, SO THE CAPS SHOULD BE RATED AT 100ÖÄÃ+.
3) É ENDED UP WITH A FINAL SERIES RESISTANCE VALUE (100 OHM + POT) OF 2.75Ë.
   É SPECULATE THAT ONE COULD PROBABLY USE 2ÍÆÄ AND A FIXED 2.7Ë RESISTOR AND
   DO THE JOB 90% OF THE TIME. ÔHE ADJUSTMENT OF THE POT IS NOT VERY CRITICAL.
   ÃHANGES OF +/- 1Ë MADE LITTLE DIFFERENCE IN THE PERFORMANCE OF THE CIRCUIT.

ÈOPE IT WORKS AS WELL FOR YOU AS IT DID FOR ME.
*****************************************************************************


  Á ÓÉÍÐÌÅ ÍÏÄÅÍ ÐÒÏÔÅÃÔÏÒ
  ------------------------

ÉF YOU LIVE IN AN AREA OF THE COUNTRY THAT IS PRONE TO ELECTRICAL STORMS,
LIVE IN AN APARTMENT, HAVE ELECTRIC HEAT OR A DEHUMIDIFIER, THEN IT IS
CONCEIVABLE YOU NEED SPIKE PROTECTION FOR YOUR MODEM.

ÓPIKE DEFLECTORS ARE COMMERCIALLY AVAILABLE BUT FOR WHAT THEY DO AND THE
PARTS INVOLVED, MOST ARE VERY OVERPRICED.  ÆOR A RETAILER TO SELL YOU A
MODEM PROTECTOR IT MUST BE Õ/Ì LISTED IN THE Õ.Ó.Á. OR ÃÓÁ APPROVED IF YOU
LIVE IN ÃANADA.  ÉT MAY ALSO, DEPENDING ON YOUR PHONE COMPANY, NEED TO BE
LISTED AS APPROVED EQUIPMENT BEFORE ATTACHING TO A PHONE LINE.  ÁLL THIS
CERTIFICATION AND TESTING COSTS MONEY AND, AS ALWAYS, IT IS THE END USER 
THAT PAYS.

ÉF YOU ARE INTERESTED IN BUILDING YOUR OWN SPIKE DEFLECTOR, THEN READ ON. 
ÏTHERWISE É DO SUGGEST THAT YOU BUY A GOOD COMMERCIALLY AVAILABLE UNIT. 
ÏNE THING TO KEEP IN MIND WHEN BUYING A UNIT, IS TO READ THE WARRANTY, OR
GUARANTEE.  ÍOST WARRANTIES ONLY COVER THE SPIKE DEFLECTOR ITSELF AND DO 
NOT COVER YOUR MODEM OR COMPUTER WHICH IS WHY YOU NEED SPIKE PROTECTION IN 
THE FIRST PLACE.

ÔHE SPIKE DEFLECTOR É SUGGEST TO YOU IS DESCRIBED BELOW.  É HAVE HAD MINE
ON-LINE 24 HOURS PER DAY FOR NEARLY TWO YEARS.  ÉN THAT TIME É HAVE BEEN 
HIT WITH SEVERAL LIGHTNING STORMS, SEEN THE DEVICE ACTIVATE TO DISCHARGE 
THE LOAD, AND NOT SUFFERED ANY DAMAGE TO THE DEVICE, THE MODEM, OR THE 
COMPUTER.

ÎÏÔÅ: ÉT IS VERY UNLIKELY FOR YOUR PHONE LINE TO TAKE A DIRECT LIGHTNING
STRIKE.  ÉF YOU DO, THEN THERE IS LITTLE YOU CAN DO FOR PROTECTION.  Á
DIRECT HIT IS JUST AS LIKELY TO BURN YOUR HOUSE DOWN AS IT IS TO FRY YOUR
MODEM.  Á SPIKE DEFLECTOR WILL ONLY OFFER A DEGREE OF SECURITY FOR MOST
INDIRECT HITS.


ÔHE SPIKE DEFLECTOR.
-------------------

ÐARTS REQUIRED:

1.    2) ÎÅ-2È ÎEON LAMPS (ÒADIO ÓHACK PART NO. 272-1102)
2.    2) 22K OHM RESISTORS (ÒADIO ÓHACK PART NO. 271-1339)
3.    1) ÄUPLEX PHONE ÊACK (ÒADIO ÓHACK PART NO. 279-357)
4.    1) ÍODULAR MALE ÊACK (ÒADIO ÓHACK PART NO. 279-390)

... ÁLSO REQUIRED IS A PIECE OF INSULATED HOOK-UP WIRE (16-18 Á×Ç).


ÄIRECTIONS:
----------

ÁLL CONNECTIONS SHOULD BE SOLDERED AND ALL BARE WIRES, AND LEADS, SHOULD BE
INSULATED.  ÙOU MIGHT USE SPAGHETTI INSULATION SCAVENGED FROM SOME WIRE, OR
ELECTRICAL TAPE.  

ÎÏÔÅ:  ÉF YOU MAKE ANY MISTAKES THERE IS VERY LITTLE DANGER OF CAUSING ANY 
HARM TO YOUR PHONE LINE OR YOUR MODEM.

1) ÐÒÅÖÅÎÔ ÓÈÏÒÔ ÃÉÒÃÕÉÔÓ:  ÃOVER EACH LEAD EMANATING FROM THE ÎEON WITH 
ABOUT ONE HALF AN INCH OF INSULATING MATERIAL.

2) ÃÒÅÁÔÅ Á ÎÅÏÎ ÒÅÓÉÓÔÏÒ ÐÁÉÒ:  ÁS CLOSE TO THE BODY OF A RESISTOR AS
POSSIBLE CONNECT ONE LEAD OF ONE ÎEON. ÓOLDER, REMOVE EXCESS LEAD AND TAPE.
ÙOU SHOULD NOW HAVE TWO UNITS THAT ARE COMPOSED OF A ÎEON AND A RESISTOR.

3) ÃÒÅÁÔÅ ÇÒÏÕÎÄ ÐÁÔÈ:  ÁTTACH THE FREE ENDS OF BOTH RESISTORS TOGETHER 
WITH A LENGTH OF INSULATED (16-18 Á×Ç) WIRE. ×IRE MUST BE LONG ENOUGH TO 
REACH A GOOD GROUND CONNECTION.  ÍEASURE FROM THE PHONE OUTLET TO THE 
NEAREST 110 VOLT OUTLET.

4) ÃÒÅÁÔÅ ÐÈÏÎÅ ÐÁÔÃÈ-ÃÏÒÄ:  ÃUT MALE TO MALE MODULAR ÊACK LEAD IN HALF.
ÒEMOVE ABOUT ONE INCH OF THE OUTER INSULATION AND ABOUT ONE-HALF INCH OF
INSULATION FROM THE MIDDLE (RED AND GREEN) TWO CONDUCTORS.  ÆOLD THE OUTER
WIRES (BLACK AND YELLOW) BACK ALONG THE LENGTH OF THE WIRE AND WRAP WITH
INSULATION.

5) ÆÉÎÁÌ ÃÏÎÎÅÃÔÉÏÎÓ:  ÃONNECT THE FREE END OF ONE OF THE ÎEONS TO ONE OF 
THE EXSPOSED MIDDLE CONDUCTORS, AND THE OTHER ÎEON TO THE OTHER, INSULATED 
FROM EACH OTHER.


ÔEST ÕNIT:
---------

ÉNSERT ÍALE CONNECTOR INTO THE DUPLEX PHONE JACK AND INSERT THE DUPLEX JACK
INTO YOUR TELCO'S PHONE JACK AND PLUG YOUR EXISTING PHONE OR MODEM INTO THE
OTHER JACK ON THE DUPLEX CONNECTOR.  ÄO NOT CONNECT THE LONG GROUNDING WIRE
JUST YET.

ÔEST YOUR PHONE OR MODEM FOR PROPER OPERATION, BOTH DIALING OUT, AND
RECEIVING CALLS.  ÉT IS PERFECTLY Ï.Ë. IF ONE OR BOTH ÎEONS FLASH SLIGHTLY
WHILE DIALING OR RINGING.  ÐAY PARTICULAR ATTENTION TO SEE THAT AFTER
A CALL (OUT-GOING OR INCOMMING) THAT YOU CAN PROPERLY HANG UP AND BE READY
FOR THE NEXT CALL WITHOUT HAVING TO ADJUST THE SPIKE DEFLECTOR.
ÉF THE NEONS DO NOT FLICKER WHEN DIALING OUT, OR WHEN A CALL IS BEING
RECIEVED, YOU HAVE MADE A MISTAKE. ÃHECK YOUR WIRING.  ÉF THE LINE IS
CONSTANTLY BUSY TO AN INCOMMING CALL THERE IS ALSO A MISTAKE IN THE WIRING.

ÉF TESTS ARE GOOD SO FAR, CONNECT THE LONG WIRE TO THE FACE-PLATE SCREW OF
THE NEAREST 110 VOLT OUTLET OR ANY GOOD KNOWN GROUNDING CONDUCTOR, ×ATER 
PIPE, ETC.

ÒE-TEST THE SPIKE DEFLECTOR.  ÉT SHOULD FLASH OCCASIONALLY, BUT PERMIT YOU 
TO RECEIVE INCOMING CALLS, AND TO DIAL OUT.  ÉF IT DOES NOT PERMIT NORMAL
PHONE OPERATIONS, THERE IS MOST LIKELY A MISTAKE IN YOUR CONNECTIONS.

×HAT YOU HAVE ACCOMPLISHED, IF ALL HAS GONE WELL TO THIS POINT, IS TO 
PROTECT YOUR MODEM FROM ANY OVER VOLTAGE CONDITION.

ÙOUR PHONE COMPANY HAS A VESTED INTEREST IN NOT HAVING YOUR EQUIPMENT
HIT BY LIGHTNING AND HAS FUSES ON THE SYSTEM TO PROTECT YOU.  ÔHE PROBLEM 
IS THAT THE FUSES THEY EMPLOY ARE NOT ALWAYS FAST ENOUGH TO PROTECT YOUR 
MODEM OR YOUR COMPUTER.  ÔHEY ARE ONLY INTERESTED IN PROTECTING PHONES.
ÔHE DEVICE YOU HAVE JUST BUILT WILL SHUNT ANY VOLTAGE OVER 70 TO GROUND AND
IF YOU ARE HIT BY 200 OR MORE, YOUR SAVING GRACE IS THAT THE SPIKE
DEFLECTOR WILL GREATLY LENGTHEN THE TIME THE FUSES ON YOUR LINE HAVE TO
RESPOND TO THE ANOMALY.
                           -------------------------
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