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RCA-GE_CTC186_187_Training


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CTC186/187
SERVICE ADJUSTMENTS - CHASSIS/TUNER ALIGNMENT
Service Menu
   The service menu is provided to facilitate instrument            volume +/- keys before other parameters may be selected.
alignment and service adjustments. The service menu is              NOTE: If the channel up/down buttons are pressed without
accessed by pressing two combinations of buttons on the front               the correct security pass-number set, the service
panel keyboard. With the instrument on press and hold the                   mode is exited.
menu button and simultaneously press the power button, then           There are three main groups of parameters: the service
while continuing to hold the menu button release the power          adjustment parameters, the chassis alignment parameters, and
button and press the volume + button. The instrument should         the tuner alignment parameters. The chassis and tuner
immediately display a one line menu on the screen, release          alignment parameters are each preceded by a security pass-
buttons.                                                            number for added protection. Most of the service adjustment
                                                                    and chassis alignment parameters correspond to individual
 PARAMETER                                           VALUE          (unpacked) register fields in the T-Chip. When these
 CONTROLLED                                     CONTROLLED          parameters are modified, the T-Chip and the corresponding
 BY                                                     BY          EEPROM location is updated.
 CHAN v
      w                                          VOLUME +/-         NOTE: When setting the kine bias/drive parameters, the
                 P00                    V00
                                                                            Menu button may be used to enable the vertical
                                                                            collapse setup line-it functions as a toggle. The setup
                                                                            line has the following characteristics: -Selects S-
   The decimal value on the left is the parameter number and                Video source (make sure no signal is connected to
the decimal value on the right is the current value of that                 the S-Video input); -Contrast is automatically set to
parameter. The channel up and down buttons increment and                    minimum; -Brightness is set to 7.5 IRE; -Vertical kill
decrement the parameter number. The volume + and the                        is enabled. When the setup line is toggled off, the
volume - buttons adjust the current value of that parameter.                characteristics modified above will return to their
There are three parameter catagories which are used for                     prior settings. Changing to another parameter (with
security reasons. They are employed to protect the factory                  channel up/down buttons) will also toggle off
alignments from being modified by the user. The first security
parameter, 00, requires a specific value to be selected with the

SERVICE ADJUSTMENTS
NOTE: All service adjustments, except Focus and Screen              Vertical Size
         adjust, are bus controlled. They are accessable only         1. Enter parameter # 06 (see chart).
         through entry of the correct parameter #. See the
         Service Menu Chart in this service data.                     2. Adjust value range to provide approximately 1/4 inch
Focus Adjust                                                              overscan at top and bottom of screen.
  Adjust focus control to provide best overall picture focus.       Set Up Position (Collapsed Raster Service Line)
Horizontal Frequency                                                   Access to the set up position (collapsed raster service line)
                                                                    is allowed only during adjustment of the red, green and blue
 1. Enter parameter # 01 (see chart).                               bias and drive parameters. See color temperature adjustment
 2. Adjust value range for stable or slowly moving horizontal       procedure.
    lines.                                                          High Voltage
Horizontal Phase                                                       High voltage on this chassis is NOT adjustable. To check
 1. Enter parameter # 02 (see chart).                               high voltage connect a VTVM with high voltage probe to the
 2. Adjust value range to center picture left to right.             picture tube high voltage anode, negative lead to picture tube
Pincushion EW DC (some models)                                      ground strap (use 500 volt scale).
 1. Enter parameter # 03 (see chart).                               NOTE: The meter (VTVM with high voltage probe) used for
                                                                              measuring high voltage must have a resistance of
 2. Adjust value range to provide approximately 1/2 inch                      1000 megohm or more and be accurate within 5% or
    overscan left and right sides.                                            better.
Pincushion EW Amplitude (some models)                                  Nominal high voltage for this chassis (at maximum beam
 1. Enter parameter # 04 (see chart).                               current) is 25.1 kV (19 & 20 inch), 26.4 kV (25, 26 & 27 inch)
                                                                    and 29.1 kV (31 & 35 inch) when measured with a VTVM
 2. Connect crosshatch generator to antenna terminals.
                                                                    (with high voltage probe) as described and must not exceed
 3. Adjust value range for straight vertical lines left and right   29.0kV (19 thru 27 inch) and 32.0kV (31 & 35 inch) under
    sides.                                                          any circumstances.
Vertical DC Adjust
 1. Enter parameter # 05 (see chart).
 2. Adjust value range to center picture top to bottom.




                                                              Page 3-1
SERVICE ADJUSTMENTS (Continued)
X-Radiation Protection Shutdown Check
                                                                    2. Allow for instrument warm up and adjust user controls or
NOTE: When service is required, especially in the                      maximum brightness and contrast levels.
         horizontal deflection, high voltage, or regulated B+
         circuits the X-Radiation Protection circuit should be      3. Locate the x-ray protect test stakes labeled XRP1 and
         tested for proper operation as follows:                       XRP2(J4901 located to the rear and center of the chassis).
 1. Apply 120 volts AC using a variac (variable AC)                 4. Momentarily short stake XRP1 to stake XRP2. The
    transformer for accurate AC input voltage.                         instrument must shutdown and then restart.
                                               SERVICE MENU CHART
NOTE: During the Service Menu Mode the channel up/dn will change the parameter # while the volume +/- will change the value
        range. Therefore channel changes, when in the service menu mode, must be accomplished by random access using the
        remote transmitter. To access channels 100 thru 125, press and hold the channel 1 button on the remote control until the
        number 1, and two dashes are displayed on the screen, then press the second two digits.
Parameter #        Parameter Name                             Value Range                 Comment:
Chan to                                                       Vol to
Change                                                        adjust
   00              Pass No. for Serv. adjust                   Must set to 76             May not advance until value set
Service Adjustment Parameters
   01               Horiz. Freq.                                 00-63                     Sync is killed
   02               Horiz. Phase                                 00-15
   03               EW DC (width)                                00-15                     Some models
   04               EW Amplitude                                 00-07                     Some models
   05               Vertical DC                                  00-15
   06               Vertical size                                00-31
   07               Red Bias                                     00-127                    Press Menu button for setup line
   08               Green Bias                                   00-127                    Press Menu button for setup line
   09               Blue Bias                                    00-127                    Press Menu button for setup line
   10               Red Drive                                    00-63                     Press Menu button for setup line
   11               Green Drive                                  00-63                     Press Menu button for setup line
   12               Blue Drive                                   00-63                     Press Menu button for setup line
   13               Security pass no. for chassis align          Must set to               May not advance to higher param.
                    parameters                                   77                        until value set
Chassis Alignment Parameters
  14              PLL Tuning                                     00-63
  15              4.5 MHz Trap                                   00-7
  16              Video Level                                    00-7
  17              FM Level                                       00-15
  18              B+ Trim                                        00-15                      CTC175 only
  19              RF AGC                                         00-31
  20              D-PIP chroma                                   00-127
  21              D-PIP tint                                     00-255                    Wraps around
  22              D-PIP brightness                               00-31
  23              D-PIP contrast                                 00-63
  24              Factory tint                                   00-63
  25              dbx: input level                               00-15                     Refer to DBX alignment procedure
  26              dbx: stereo VCO free run freq.                 00-63                     Refer to DBX alignment procedure
  27              dbx: SAP VCO free run freq.                    00-15                     Refer to DBX alignment procedure
  28              dbx: stereo low pass filter                    00-63                     Refer to DBX alignment procedure
  29              dbx: SAP band pass filter                      00-15                     Refer to DBX alignment procedure
  30              dbx: wideband alignment                        00-63                     Refer to DBX alignment procedure
  31              dbx: spectral alignment                        00-63                     Refer to DBX alignment procedure
  32              Security pass no. for tuner alignment          Must set to               May not advance to higher param.
                                                                 78                        until value set
                                                           Page 3-2
CTC186/187
SERVICE ADJUSTMENTS - CHASSIS ALIGNMENT
Test Equipment Required
External Marker Generator-Capable of furnishing 41.25
MHz, 45.75 MHz and 4.5 MHz markers and AF modulation.             FM Level (Wideband Audio)
Digital Voltmeter                                                  1. Enter parameter # 17 (see chart).
External Bias Supply-Well regulated, isolated AC operated          2. Connect signal generator to sound output TP1201 (pin 55
variable DC bias supply.                                              of U1001) with 4.5 MHz carrier, 1 KHz modulation, with
                                                                      25 KHz deviation
NOTE: All alignment adjustments, are bus controlled. They
         are accessable only through entry of the correct code.    3. Apply 4.0 volts DC bias to IF AGC TP2305.
         See the parameter # and value range adjustment            4. Connect oscilloscope to TP1202 (WBA output pin 3
         chart in this service data.                                  U1001).
                                                                   5. Adjust value range for 1.2 volt p-p indication of the 1KHz
PLL Tuning (IF VCO Free Run)                                          component (a 1.8 KHz component also exists).
 1. Enter parameter # 14 (see chart).
 2. Apply 4.0 volt DC bias to IF AGC TP2305 (pin 14 of            RF AGC
    U1001).                                                          The RF AGC has been preset at the time of manufacture for
 3. Short RF AGC TP7102 (tuner side of R2313) to ground.          optimum operation over a wide range of RF signal input
 4. Apply 41.25 MHz marker (300 mV output)) to IF input           conditions. Readjustment should not be required unless
    (pin 1 of SF2301).                                            the tuner has been repaired, IC 1001 has been replaced, IC
 5. Connect oscilloscope to TP1201 (pin 55 of U1001). Set         3101 has been replaced, IC 3201 has been replaced, or
    scope for 1uS per division.
                                                                  unusual signal conditions exist such as:
 6. Adjust parameter reading to provide a 2.2uS sine wave
    response                                                        1. Cable TVadjacent channel interference.
                                                                    2. Picture bending and/or channel 6 color beats which are
                                                                       usually due to excessive RF signal input. This occurs
NOTE: If a 2.2uS sine wave response cannot be achieved set             when the receiver location is too close to the transmitting
      parameter reading to approximate mid range and                   tower. It may also occur when the receiver is connected
      adjust L2302 for a 2.2uS response.                               to an antenna distribution system where the RF signal has
                                                                       been amplified. The signal should be attenuated at the
         L2302 is preset at the time of manufacture and                antenna input to a more satisfactory level.
         should require no further adjustment unless a              3. Picture Noise caused by broadcast noise or weak
         2.2uS response cannot be achieved during the                  signal. If the broadcast is clean and the received signal
         parameter adjustment.                                         is at least 1 mV, the picture will be noise free in any area.

4.5 MHz Trap
 1. Enter parameter # 15 (see chart).
                                                                  NOTE: Adjustment of the RF AGC parameters may not have
 2. Short RF AGC TP7102 (tuner side of R2313) to ground.                any visible effect except under unusual conditions.
 3. Apply 45.75 MHz (300mV output) and 41.25 MHz                        Ajusting the RF AGC to one extreme of its
    (100mV output) to IF input (pin 1 of SF2301).                       parameter limits will usually provide a relatively
 4. Connect oscilloscope to TP2302 (pin 63 of U1001).                   poor signal-to-noise ratio, while adustment to the
 5. Adjust parameter reading to produce minimum 4.5 MHz                 other extreme of its parameter limits will cause a
    indication (sine wave just stops losing amplitude).                 degradation of overload conditions such as channel
                                                                        6 color beats or Cable TV adjacent channel
                                                                        interference. If the RF AGC parameter setting is
Video Level                                                             adjusted, check all local channels for proper
 1. Enter parameter # 16 (see chart).                                   operation. Use weakest local signal to adjust RF
                                                                        AGC parameter setting.
 2. Connect color bar generator to anteanna input (100%
    modulation) set for super pulse display.
 3. Connect oscilloscope to TP2302 (pin 63 of U1001).
 4. Adjust value range to produce 2.0 volt p-p (sync to white)
    response.




                                                            Page 3-3
CTC186/187
SERVICE ADJUSTMENTS - COLOR TEMPERATURE ADJUSTMENT (Preferred Method)
NOTE: See service adjustment chart for sequence required          NOTE: Each time a parameter is exited and a new parameter
      to obtain entry to color temperature adjustment                   is entered the Menu button (on instrument front
      parameters.                                                       panel) must be pressed to reinstate the setup line.

 1. Preset Video controls:                                         8. Set brightness and contrast controls to maximum.
    Color Set to minimum.                                          9. Enter access codes for the color drive controls (10 for
    Contrast Set to minimum.                                          red, 11 for green and 12 for blue) in random sequence.
    Brightness Set to mid-range.                                      Adjust their respective parameters to obtain a 6500
                                                                      degree kelvin color temperature (warm white) raster.
 2. Set instrument for Auxiliary Input (Channel 00) Make
    sure that there is no signal input to the SVHS input on       10. Check the low light to high light gray scale tracking
    models with SVHS jacks.                                           (black and white picture). Should any color other than
                                                                      gray or white be dominant in low light to high light areas
 3. Preset red, green and blue drive parameter values to              the color temperature settings have not been properly
    mid-range (approximate setting of 32).                            performed. Repeat the procedure if necessary.
 4. Enter parameter # 07 for red bias adjustment. Press           NOTE: Color bias adjustments affect the low light (dark)
    Menu button (on instrument front panel) for setup line.                areas while color drive adjustments affect the high
NOTE: Access to the set up line (collapsed raster service                  light (white) areas.
          line) is only allowed during adjustment of the drive
          and bias parameters.                                    D-PIP Adjustment
 5. Using an DC voltmeter, preset red, green and blue bias        NOTE: See service adjustment chart for sequence required
    parameters to provide 120 volts DC at the collector of               to obtain entry to D-PIP adjustment parameters.
    their respective output transistors on the kine socket
    circuit board.                                                 1. Enter parameter # 23 for chroma level adjustment.
NOTE: When the voltmeter probe is placed on the green                 Adjust value level to match big pix chroma level.
          cathode, the Service Menu On-Screen-Display may          2. Enter parameter # 24 for tint level adjustment. Adjust
          be difficult to read.                                       value level to match big pix tint level.
 6. Adjust the screen control to just produce a centerline
    (red, green or blue).                                          3. Enter parameter # 25 for brightness level adjustment.
                                                                      Adjust value level to match big pix brightness level.
 7. Enter parameter #s for the remaining two bias control
    colors and obtain proper mix to produce a white setup          4. Enter parameter # 26 for contrast level adjustment.
    line.                                                             Adjust value level to match big pix contrast level.


STEREO (MPX) ADJUSTMENT                                            3. Connect an AC voltmeter to MPX CBA pin #JS106,
NOTE: Make sure that the EXPANDED STEREO function                     RIGHT CHANNEL OUTPUT. This is also the
      is turned off, otherwise the stereo separation and              bottom end of R612. (Do not use the top end, or
      output amplitudes will be in error.                             oscillations may result.) Adjust the parameter value
      The following alignments must be performed in the               using the volume control buttons to set the DAC
      order given.                                                    (parameter value) for an output level as close to 489
                                                                      mV rms as possible. Each value step will change the
Set-up                                                                output level by about 25 mv.
 1. Unsolder and lift the bottom end of R1609 from the             4. Observe on an oscilloscope that the audio output at
    circuit board (end closest to Main circuit board) . This is       MPX CBA pins #5 (LEFT) and #6 (RIGHT) are
    the Wideband Audio input (WBA) to the CXA1734                     clean and undistorted.
    stereo IC.                                                     5. Confirm that the rms amplitude of both pins #5 and
 2. Connect an audio generator to the unsoldered end of               #6 are within 20 mVrms of each other.
    R1609 (WBA).
                                                                  NOTE: If the final DAC alignment value is not within
Attenuator                                                              the range of 7 - 11, check to make sure that the
1. Enter parameter # 25 (see chart)                                     signal amplitude is proper. (Do not use 1KHz,
                                                                        because the internal deemphasis filter will cause
2. Adjust the generator output for 100 Hz, 424 mV rms, +/               an amplitude error.)
   - 10 mV. This corresponds to a full 25KHz carrier
   deviation mono audio signal from the sound IF.




                                                            Page 3-4
CTC186/187
SERVICE ADJUSTMENTS - STEREO (MPX) (Continued)
Stereo VCO
   This alignment is also a course adjustment for the next          6. Average the parameter value settings from steps 4 and 5.
alignment.                                                             Set the parameter value to this averaged value. This is the
  1. Enter parameter # 26 (see chart). Remove the audio                proper alignment value for Stereo Lowpass Filter.
     generator connection from the bottom end of R1609.
     False VCO frequency will be generated if WBA input is         SAP Bandpass Filter
     not open.                                                      1. Enter parameter # 29 (see chart)
  2. Connect a frequency counter to MPX CBA pin #6. (4 x            2. Adjust audio generator for 88 KHz, 206 mV rms, +/- 10
     fH vco is automatically routed to pin #6 when in                  mv.
     parameter #26 is selected).
                                                                    3. Adjust the parameter value to 0. Observe TV screen. No
  3. Adjust the parameter value for a frequency of 62,936 Hz           star (*) should be present.
     +/- 200 Hz. (4 x fH). The frequency increment for each
     DAC step is approximately 300 Hz.                              4. Increment the parameter value once per second or slower
                                                                       until the star (*) becomes present. Record this value
SAP VCO                                                                setting. (A flashing * is OK. Usually, one more value
   This is not a direct frequency measurement. It uses the             increment will stop the flashing.)
internal status registers of the stereo IC to indicate PLL lock.
The previous alignment (STVCO) is a coarse adjust for this          5. Set the parameter value to step # 15. Observe that no * is
alignment.                                                             present. Decrement the parameter value until * once
                                                                       again becomes present. Record this value setting.
  1. Enter parameter # 27 (see chart).
                                                                    6. Average the value settings from steps 4 and 5. Set the
  2. Connect an audio generator as described in Set-up and             parameter value to this averaged value. This is the proper
     adjust for 78.67 KHz, 254 mv rms, +/- 10 mv.                      alignment value.
  3. Adjust the parameter value to 0. Observe TV screen. No
     star (*) should be present.
                                                                   Wideband/Spectral Separation
  4. Increment the parameter value once per second or slower         This alignment is for the dbx wideband detector.
     until the star (*) becomes present. Record this value
     setting. (A flashing * is OK. Usually, one more value          1. Enter parameter # 30 (see chart).
     increment will stop the flashing.)                             2. Set stereo generator for stereo left channel only signal,
  5. Set the parameter value to step # 15. Observe that no * is        300 Hz, 85 mV rms at 30%modulation.
     present. Decrement the parameter value until * once            3. Connect AC rms voltmeter to the MPX CBA pin #6.
     again becomes present. Record this value setting.              4. Set the parameter value to step # 31 (DAC midpoint).
  6. Average the paremeter value settings from steps 4 and 5.       5. Start incrementing the parameter value               (or
     Set the parameter value to this averaged value. This is the       decrementing, as necessary) while observing voltmeter
     proper alignment value for SAP VCO. Setting will                  reading. Find the parameter value setting which produces
     usually be 6 - 10. If not, verify that the previous steps         a minimum voltmeter reading (null setting). Record this
     were done properly.                                               value setting. The exact null setting will typically be
                                                                       difficult to determine, because the null range is rather
Stereo Lowpass Filter                                                  broad.
  This alignment is also a course adjustment for the next           6. Measure MPX CBA pin #5, left channel out, and check
alignment.                                                             for at least 20 dB separation between left and right
 1. Enter parameter # 28 (see chart)                                   channel outputs.
 2. Adjust audio generator for 9.4 KHz, 1.04 V rms at WBA           7. Enter parameter # 31 (see chart).
    input.                                                          8. Increase the generator from 300 Hz to 3000 Hz and repeat
 3. Set the parameter value to step # 0. Observe TV screen.            steps 3 thru 6.
    No STEREO indicator should be present.
 4. Increment the parameter value once per second or slower        NOTE: If a generator capable of producing 3000 Hz is not
    until STEREO indicator becomes present. Record this                  available, set the parameter value to the preset of 31.
    value setting. (It is OK for the STEREO indicator to
    flash. Usually, one more value increment will stop the          9. Return the generator to 300 Hz and the parameter to 30.
    flashing.)                                                     10. Increment (or decrement) the parameter value for
 5. Set the parameter value to step # 63. Observe that no              minimum voltmeter reading (null setting).
    STEREO indicator is present. Decrement the value
    until STEREO indicator once again becomes present.
    Record this value setting.




                                                             Page 3-5
CTC186/187
SERVICE ADJUSTMENTS - TUNER ALIGNMENT
Equipment Required                                       NOTE: Monitor RF AGC at + leg of C2306 (TP7102) or pin
                                                               12 of the T-Chip (U1001) and adjust for minimum
TOB Service Alignment Fixture- RCA Stock No 215568             voltage each step. Top and bottom covers must be in
                                    (TAG001)                   place with bottom cover soldered. The entire
VCR- Used as signal source for TOB service alignment           electronic tuner alignment procedure, once started,
        fixture (tuner service modulator).                     must be completed in its entirety.
DVM- Digital volt meter.
External DC Power Supply- Voltage source to power
                               service modulator.




                                    Electronic Tuner Alignment Parameters


Parameter #   Parameter Name          Value Range        Parameter #    Parameter Name            Value Range
Chan to                               Volume to          Chan to                                  Volume to
Change                                adjust             Change                                   adjust
    100       Ch. 2 secondary          00-63                 128        Ch. 50 primary              00-63
    101       Ch. 2 primary            00-63                 129        Ch. 50 single               00-63
    102       Ch. 2 single             00-63                 130        Ch. 51 secondary            00-63
    103       Ch. 6 secondary          00-63                 131        Ch. 51 primary              00 63
    104       Ch. 6 primary            00-63                 132        Ch. 51 single               00-63
    105       Ch. 6 single             00 63                 133        Ch. 57 secondary            00-63
    106       Ch. 14 secondary         00-63                 134        Ch. 57 primary              00-63
    107       Ch. 14 primary           00-63                 135        Ch. 57 single               00-63
    108       Ch. 14 single            00-63                 136        Ch. 63 secondary            00-63
    109       Ch. 17 secondary         00-63                 137        Ch. 63 primary              00-63
    110       Ch. 17 primary           00-63                 138        Ch. 63 single               00 63
    111       Ch. 17 single            00 63                 139        Ch. 76 secondary            00-63
    112       Ch. 18 secondary         00-63                 140        Ch. 76 primary              00-63
    113       Ch. 18 primary           00-63                 141        Ch. 76 single               00-63
    114       Ch. 18 single            00-63                 142        Ch. 83 secondary            00-63
    115       Ch. 13 secondary         00-63                 143        Ch. 83 primary              00-63
    116       Ch. 13 primary           00-63                 144        Ch. 83 single               00-63
    117       Ch. 13 single            00-63                 145        Ch. 93 secondary            00-63
    118       Ch. 34 secondary         00-63                 146        Ch. 93 primary              00-63
    119       Ch. 34 primary           00-63                 147        Ch. 93 single               00-63
    120       Ch. 34 single            00-63                 148        Ch. 110 secondary           00-63
    121       Ch. 37 secondary         00-63                 149        Ch. 110 primary             00-63
    122       Ch. 37 primary           00-63                 150        Ch. 110 single              00-63
    123       Ch. 37 single            00-63                 151        Ch. 117 secondary           00-63
    124       Ch. 48 secondary         00-63                 152        Ch. 117 primary             00 63
    125       Ch. 48 primary           00-63                 153        Ch. 117 single              00-63
    126       Ch. 48 single            00-63                 154        Ch. 125 secondary           00-63
    127       Ch. 50 secondary         00-63                 155        Ch. 125 primary             00-63
                                                             156        Ch. 125 single              00-63


                                                    Page 3-6
CTC186/187
SERVICE ADJUSTMENTS - TUNER ALIGNMENT (Continued)
Tuner Coil Alignment (Mechanical)                             12. Set parameter value range to 31.
                                                              13. Expand or compress L105 for minimum RF AGC
NOTE: The tuner coil alignment is preset at the time of           voltage.
      manufacture and should require no further
                                                              14. Enter parameter 155 and set parameter value range to 31.
      adjustment.The following recommended procedure
      should be performed only in the unlikely event that     15. Expand or compress L104 for minimum RF AGC
      complete tuner alignment is necessary (when                 voltage.
      necessary this procedure must be performed prior to     16. Enter parameter 156 and set parameter value range to 31.
      the electronic tuner alignment). Bottom cover must      17. Expand or compress L102 for minimum RF AGC
      be in place and soldered. Use a plastic or wooden           voltage.
      stick for knifing coils.
                                                              18. Manually tune instrument and tuner service modulator to
                                                                  channel 50 (band 2) and enter parameter 127.
                                                              19. Set parameter value range to 31.
 1. Manually tune instrument and tuner service modulator to
    channel 125 (Band 3) and enter parameter # 154.           20. Expand or compress L113 for minimum RF AGC
                                                                  voltage.
 2. Connect DVM to tuner side of R7525.
                                                              21. Enter parameter 128 and set parameter value range to 31.
 3. If voltage reading is not between 4.55V and 4.75V
    expand or compress L303 to set voltage within these       22. Expand or compress L111 for minimum RF AGC
    limits.                                                       voltage.
 4. Manually tune instrument and tuner service modulator to   23. Enter Parameter 129 and set parameter value range to
    channel 50 (Band 2) and enter parameter # 127.                31.
 5. Retain DVM connection step 2.                             24. Expand or compress L107 for minimum RF AGC
                                                                  voltage.
 6. If voltage reading is not between 4.80V and 5.00V
    expand or compress L304 to set voltage within these       25. Manually tune instrument and service modulator to
    limits.                                                       channel 17 (band 1) and enter parameter 109.
 7. Manually tune instrument and tuner service modulator to   26. Set parameter value range to 31.
    channel 17 (Band 1) and enter parameter # 109.            27. Expand or compress L114 for minimum RF AGC
 8. Retain DVM connection step 2.                                 voltage.
 9. If voltage reading is not between 4.40V and 4.60V         28. Enter parameter 110 and set parameter value range to 31.
    expand or compress L305 to set voltage within these       29. Expand or compress L112 for minimum RF AGC
    limits.                                                       voltage.
10. Manually tune instrument and tuner service modulator to   30. Enter parameter 111 and set parameter value range to 31.
    channel 125 (band 3) and enter parameter 154.             31. Expand or compress L106 for minimum RF AGC
11. Connect DVM to positive leg of C7503 (RF AGC to               voltage.
    tuner).                                                   32. Perform electronic tuner alignment in its entirety.




                                                        Page 3-7
CTC186/187

                                                   TUNER VOLTAGE
 U7301
                                                       CHARTS
                                                  OFF-AIR OPERATION        U7401
 Pin     Lo V Chan.         Hi V Chan.                 UHF Chan.                 Lo V      Hi V      UHF
 No.    2           6         7        13        14        40        69    1.    1.75V     2.1IV    1.72V
  1. 5.43V       5.42V     5.38V     5.38V     5.30V     5.22V     5.30V   2.    2.11V     2.11V    2.11V
  2. 2.93V       2.98V     2.95V     2.95V     3.18V     3.16V     3.18V   3.    2.11V     2.11V    2.11V
  3. 7.80V       7.81V     7.75V     7.69V     7.56V     7.51V     7.56V   4.    4.78V     4.78V    4.78V
  4. 2.99V       2.99V     2.96V     2.97V     3.18V     3.16V     3.18V   5.    4.71V     4.71V    4.71V
  5. 7.82V       7.81V     7.75V     7.71V     7.56V     7.51V     7.56V   6.       0V       0V         0V
  6.     0V           0V     0V           0V     0V        0V        0V    7.    1.32V     1.32V    1.34V
  7. 3.06V       3.06V     3.04V     3.01V       0V        0V        0V    8.    11.5V       0V         0V
  8. 9.06V       9.03V     8.97V     8.89V     8.84V     8.80V     8.84V   9.    7.41V     7.41V        0V
  9. 3.02V       3.02V     2.98V     2.98V     3.36V     3.33V     3.36V   10.   4.85V     4.85V    4.85V
 10. 3.25V       3.25V     3.22V     3.19V     2.88V     2.87V     2.88V   11.   2.30V     2.30V    2.30V
 11. 4.94V       5.00V     5.06V     5.02V     9.62V     9.58V     9.62V   12.   2.30V     2.30V    2.30V
 12. 3.25V       3.23V     3.22V     3.19V     2.87V     2.87V     2.88V   13.      0V       0V         0V
 13.     0V           0V     0V           0V     0V        0V        0V    14.   0.60V     0.60V    0.60V
 14. 9.05V       9.04V     8.97V     8.90V     5.43V     5.39V     5.46V
 15. 3.43V       3.43V     3.40V     3.37V     2.88V     2.84V     2.88V   Q7101
 16. 3.44V       3.43V     3.40V     3.38V     2.89V     2.89V     2.89V           Lo V       Hi V           UHF
                                                                                    2           7             14
                                                                           Gl        0V            0V        4.84V
 U7501
                                                                           G2      5.03V      6.54V          7.19V
 Pin           Lo V                Hi V                   UHF              D       0.16V      0.20V          11.3V
 No.     2            6       7           13     14        40        69    S       0.19V      0.17V          4.83V
  1. 1.36V       1.96V     1.58V     1.93V     1.74V     2.90V     4.84V
  2. 1.36V       1.96V     1.58V     1.93V     1.74V     2.90V     4.84V   Q7102
                                                                           Gl      4.64V      4.58V          4.61V
  3. 1.35V       1.95V     1.57V     1.92V     1.73V     2.89V     4.83V
                                                                           G2      5.32V      6.85V          7.19V
  4. 33.0V       33.0V     33.0V     33.0V     33.0V     33.0V     33.0V
                                                                           D       11.3V      l1.2V          11.4V
  5. 1.06V       1.74V     1.47V     1.87V     1.46V     2.53V     4.08V
                                                                           S       4.08V      4.20V          11.3V
  6. 1.06V       1.74V     1.47V     1.87V     1.46V     2.54V     4.09V
  7. 1.06V       6.05V     4.09V     7.03V     3.95V     11.8V     23.2V
                                                                           Q7401
  8.   0.68V     4.57V     3.46V     6.19V     4.41V     12.3V     24.0V
                                                                           E         0V            0V          0V
  9.   1.01V     1.54V     1.39V     1.76V     1.52V     2.60V     4.19V
                                                                           B       0.60V      0.60V          0.60V
 10.   1.01V     1.54V     1.39V     1.76V     1.52V     2.60V     4.19V
 11.      0V        0V        0V        0V        0V        0V        0V   C       2.06V      3.85V          17.8V
 12.   1.05V     1.75V     1.36V     1.72V     1.44V     2.51V     4.15V
 13.   1.05V     1.75V     1.36V     1.72V     1.44V     2.51V     4.15V   Q7402
 14.   1.01V     6.10V     3.24V     5.92V     3.78V     11.6V     23.6V   E       11.4V      11.2V          11.3V
                                                                           B       11.3V      10.5V          10.6V
                                                                           C     -14.9V       11.1V          11.2V


                                                                           Q7403
                                                                           E         0V            0V          0V
                                                                           B       0.70V      0.70V            0V
                                                                           C       0.10V      0.10V          11.3V


                                                                           Q7404
                                                                           E       11.4V      11.2V          11.3V
                                                                           B       11.0V      10.9V          10.6V
                                                                           C       0.llV      0.llV          11.3V


                                                          Page 3-8
CTC186/187

                                                        TUNER VOLTAGE
  U7301
                                                           CHARTS
                                                       CABLE OPERATION       U7401
  Pin             Band 1            Band 2               Band 3                    Band 1     Band 2   Band 3
  No.         2       17      18         50       51         75        99            2         18           51
   1. 5.44V         5.40V   5.41V      5.40V     5.30V     5.28V   5.48V     1.    1.75V      1.74V     1.74V
   2. 2.99V         2.96V   2.96V      2.96V     3.18V     3.17V   3.00V     2.    2.11V      2.11V     2.11V
   3. 7.80V         7.78V   7.77V      7.75V     7.57V     7.57V   7.89V     3.    2.11V      2.11V     2.11V
   4. 2.99V         2.96V   2.96V      2.97V     3.18V     3.17V   3.00V     4.    4.78V      4.78V     4.78V
   5. 7.82V         7.78V   7.75V      7.77V     7.56V     7.57V   7.89V     5.    4.71V      4.71V     4.71V
   6.     0V           0V     0V            0V     0V         0V        0V   6.       0V         0V          0V
   7. 3.06V         3.04V   3.05V      3.05V       0V         0V   3.08V     7.       NC         NC         NC
   8. 9.02V         9.01V   8.97V      8.89V     8.84V     8.83V   9.14V     8.    11.5V         0V          0V
   9. 3.02V         3.02V   2.98V      2.98V     3.36V     3.35V   3.01V     9.    7.47V       7.42V         0V
  10. 3.25V         3.23V   3.22V      3.23V     2.88V     2.87V   3.28V     10.   4.85V       4.85V    4.85V
  11. 4.96V         5.04V   5.06V      5.16V     9.62V     9.58V   5.14V     11.   2.30V       2.30V    2.30V
  12. 3.26V         3.23V   3.22V      3.23V     2.87V     2.87V   3.28V     12.   2.30V       2.30V    2.30V
  13.     0V           0V     0V            0V     0V         0V        0V   13.      0V         0V          0V
  14. 9.05V         9.00V   8.97V      9.00V     5.43V     5.42V   9.13V     14.   0.60V       0.60V    0.60V
  15. 3.43V         3.41V   3.42V      3.41V     2.88V     2.87V   3.46V
  16. 3.41V         3.41V   3.40V      3.41V     2.89V     2.89V   3.47V     Q7101
                                                                                     Band 1      Band 2          Band 3
                                                                                       2           17             51
  U7501
                                                                             Gl          0V            0V         4.84V
                                                                             G2      5.05V          4.17V         7.19V
  Pin             Band 1           Band 2                Band 3
                                                                             D           0V         0.10V         11.3V
  No.     2           17     18         50       51         75         99
                                                                             S       0.10V          0.10V         4.83V
   1. 1.36V         4.63V   1.30V      5.52V     1.20V     2.21V   2.86V
   2. 1.36V         4.63V   1.30V      5.52V     1.20V     2.21V   2.86V
                                                                             Q7102
   3. 1.36V         4.63V   1.30V      5.52V     1.20V     2.21V   2.86V
                                                                             Gl      4.59V          4.65V         4.61V
   4. 33.0V         33.0V   33.0V      33.0V     33.0V     33.0V   33.0V
                                                                             G2      5.44V          4.50V         7.19V
   5. 1.06V         3.62V   1.16V      4.68V     0.99V     1.90V   2.54V
                                                                             D       11.3V          l1.2V         11.1V
   6. 1.06V         3.62V   1.16V      4.68V     0.99V     1.90V   2.54V
                                                                             S       4.08V          3.71V         11.0V
   7. 1.06V         19.8V   1.78V      27.6V     0.54V      7.2V   11.9V
   8.   0.68V       24.2V   1.03V      25.3V     0.86V     7.63V   12.5V
                                                                             Q7401
   9.   1.01V       4.22V   1.10V      4.38V     1.01V     1.96V   2.62V     E           0V            0V           0V
  10.   1.01V       4.22V   1.10V      4.38V     1.01V     1.96V   2.62V
                                                                             B       0.60V          0.60V         0.60V
  11.      0V          0V      0V         0V        0V        0V      0V
  12.   1.05V       4.36V   1.07V      4.76V     0.99V     1.86V   2.66V     C       2.06V          1.65V         1.00V
  13.   1.05V       4.36V   1.07V      4.76V     0.99V     1.86V   2.66V
  14.   1.01V       25.2V   1.12V      28.1V     0.54V     6.91V   12.7V     Q7402
                                                                             E       11.3V          11.4V         11.4V
                                                                             B       11.4V          10.6V         10.6V
                                                                             C      -14.5V          11.2V         11.2V


                                                                             Q7403
                                                                             E           0V            0V           0V
                                                                             B       0.70V          0.70V           0V
                                                                             C       0.10V          0.10V         11.3V


                                                                             Q7404
                                                                             E       11.4V          11.4V         11.3V
                                                                             B       11.0V          10.9V         10.6V
                                                                             C       0.llV          0.llV         11.3V

                                                            Page 3-9



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