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13

Symptom

Possible Fault

POWER ON LED

Check AC power source, polarity and power line connections.

does not light.

Check for proper seating of plug in DC power jack

Unit comes on, but

Check all antenna connections on rear panel. Make sure

no signals heard

cables go to correct connectors in Receiver

Noise received cannot

Received noise may not be locally generated. Follow  nulling

be nulled

instructions carefully. Make sure you try both settings of  PHASE
RANGE switch and  the FREQ RANGE switch when nulling if
difficulty is noted. If frequency is above 20 MHz, set the FREQ
RANGE switch to the HI position.  NOISE GAIN control may be set
too high initially.  The noise antenna length may be too great,
particularly if the noise is severe.  Shorten the noise antenna length
until a satisfactory null can be obtained with the NOISE GAIN
control in its mid range.  Change the noise antenna
polarization (horizontal or  vertical) to agree with that of the main
station antenna.  If you can approximate the location of the noise
source, place a short external noise antenna as close to the source
as you can, or use a short dipole facing toward the noise source as
a noise antenna.  

NOTE:  The short wire noise

antennas supplied with the unit are not adequate to cancel
local power line noise or other noise generated outside the
home.  You will need to install an outside antenna.  See
Section 3, NOISE ANTENNA for suggestions on antenna size
and location.  

If problem persists, contact Timewave Customer

Service Department.

Noise received on noise antenna is too low.  Noise received on noise
antenna is different from that received by main antenna.  To determine
if this is the case, perform the following procedure:

(1) Connect up the unit as described in the manual.  Turn the unit
power on.

(2) Turn both the NOISE PHASE and NOISE GAIN controls fully
CCW.

(3) Now with the main antenna connected, note the S meter reading
and listen to the character of the noise (is it a "buzz" or a "crackle",
etc.?)

(4) Disconnect the main antenna from the ANC-4.

(5) Turn the NOISE GAIN control CW until it is somewhere in its
mid-range and observe the S meter reading.  Is it as high as the
reading obtained in step 3?  Is the character of the noise the same as
that heard in step 3?  If the answer to both questions is "YES", you

SECTION 7

TROUBLE-

SHOOTING

Noise received cannot
be nulled.

Summary of Contents for ANC-4

Page 1: ...ANC 4 ANTENNA NOISE CANCELLER for Reducing Locally Generated Noise Instruction Manual Revision 2 2a March 17 2011...

Page 2: ...tory We cannot be responsible for damage caused by accidents abuse misuse improper installation or unauthorized attempts to repair the unit Timewaveserviceworkperformedinconnectionwiththiswarrantyiswa...

Page 3: ...ng Hang Time For Break In CW Or AMTOR PACTOR Use 5 Broadcast Station Notch 5 Broadcast Band Filter 5 CONNECTIONS 8 Power Requirements 8 Vehicular Operation 8 Main Antenna Input 8 Radio Input 8 Noise A...

Page 4: ...E 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 Front Panel Controls 6 Rear Panel Connectors 6 Connection Diagram 7 Printed Circuit Board Parts Placement 16 Principle of Operation 16 Block Diagram 17...

Page 5: ...receiver antenna connector The DC power mating connector for the ANC 4 is suppliedwitheachunit UHF SO 239 whichmateswithaPL 259plug connectors are used for the outside antenna and the output to the re...

Page 6: ...increase the antenna output See Section 5 ACTIVE ANTENNA The unit may also be used as a diversity combiner to null interfering signals See Section 5 Thissectionletsyouget ontheair withtheANC 4asquickl...

Page 7: ...CA connector and the coax shield to the outside of the RCA connector Use the shortest length for the noise antenna that will provide a good null with the NOISE GAIN control in its mid range Using a UH...

Page 8: ...ontrol and listen for the null in the noise Switch between the NOISE PHASE and NOISE GAIN controlstoattainthelocalnoisenull Thenullobtainedisnormallygood for most of if not the entire band in which yo...

Page 9: ...7 pF capacitor between E1 and E2 To deactivate the tunable trap place the jumper JP2 in position 2 3 To attenuate signals from local broadcast stations that are picked up by the external noise antenna...

Page 10: ...Figure 2 Rear Panel Controls 6 TIMEWAVE Figure 1 Front Panel Controls...

Page 11: ...Figure 3 Connection Diagram 7 NOISE ANTENNA 12VDC FROM POWER SUPPLY TO RADIO ANTENNA INPUT OUTSIDE MAIN ANTENNA...

Page 12: ...deeper noise nulls by having the same polarization on both the noise antenna and the main antenna In either case the noise antenna should be kept as short as possible to provide a good noise null wit...

Page 13: ...used in conjunction with this pushbutton to give even greater phase nulling range at low frequencies by placing it in the HI position The FREQ RANGE pushbutton extends the frequency range over which t...

Page 14: ...pushbutton to the B position and readjust A null should be obtained in one of the two PHASE RANGE switchpositions Rememberthatthe right switchpositionisthatwhich gives the best null 7 For the deepest...

Page 15: ...e antenna may be required DONOTconnectthenoiseantennatoahighgainoutsideantennaunlessaseries attenuator is used Unless the signal is attenuated the received signals will overload the internal amplifier...

Page 16: ...ng time Typical Local Noise Types Power Line Noise Computer Noise TV Noise etc Noise Cancellation Typically 40 dB or greater Front Panel POWER switch POWER LED PHASE RANGE switch NOISE PHASE control F...

Page 17: ...ose to the source as you can or use a short dipole facing toward the noise source as a noise antenna NOTE The short wire noise antennas supplied with the unit are not adequate to cancel local power li...

Page 18: ...reading but the noise sounds different in step 5 from what it sounds like in step 3 your noise antenna is picking up noise that is not being heard by the main antenna and the noise antenna must berelo...

Page 19: ...gnal contains desired information as well as noise TheNOISEantennasignal whichcontainsmostlythelocalnoise isamplifiedand passed through a phase shift network so that its phase can be adjusted to 180 d...

Page 20: ...RADIO ANC 4 J1 J2 J3 Noise Ant LOCAL NOISE DESIRED SIGNAL Strong Strong Weaker Weaker Main Ant Figure 5 Principle of Operation 16 Figure 4 Printed Circuit Board Parts Placement...

Page 21: ...ification sheet and photo request the latest product catalog view product FAQs and read about product upgrades when available Feel free to email us if you have technical questions or comments about yo...

Page 22: ...30 150pF T1 C29 100pF C28 120pF R15 22 Q3 4124 R14 2 2K C25 100uF C32 270pF C11 1u C31 560pF R13 4 7K R31 3K R6 500 1 3 2 NOISE ANT J3 E1 1 JP3 BCB FILTER OUT IN 1 2 3 R18 3K R19 47K C26 1u R20 47K R2...

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