[IRCA] SRF-59 Alignments: Performing the Service Manual Procedure
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[IRCA] SRF-59 Alignments: Performing the Service Manual Procedure

Hello All,
     The recent availability of the Sony SRF-PSY03  Service Manual (which has 
circuitry identical to that of the SRF-59) has given  us the ability to turn 
total turkey units into screaming DX birds of prey!
     After performing seven of these full alignments,  and seeing all seven 
units operating at peak sensitivity and DX effectiveness,  it is certain to me 
that the procedure is worth the somewhat tedious  necessity of disassembly and 
reassembly of the tiny little radio.   Unfortunately, however, this process 
does require good eyesight, patience,  steady nerves, and confidence.  The 
SRF-59 is not a Heathkit, and was  certainly not designed for user-friendly 
disassembly, or  reassembly.  Understand that despite these simplified  
instructions, this little unit is still quite capable of sending beginners  to the shrink. 
Proceed at your own risk!
1)  Turn off radio.  Remove belt clip, headphones and  battery.
2)  Turn AM-FM switch to AM.
3)  Without forcing, tune dial needle to far left stop (530).
4)  Carefully note the exact position of the dial needle at this  point.
       (This is EXTREMELY important for  proper dial reassembly!)
5)  Remove the two screws from back panel.  This will  accomplish
       absolutely nothing in making the  panels separate. 
6)  Repeat to yourself, "This radio only cost 15 bucks."
7)  Place thumbnail in slot between front and back panels at the 
       bottom edge of the radio.  Work  thumbnail in slot repeatedly,
       carefully separating the front and  back panels at the bottom
       edge, first at the left side, then the  right.  This process may
       require several minutes. Do NOT  use tools!
8)  After bottom edge of radio has significant separation  between
       front and back panels, slowly work up  the left and right side
       of the radio, to increase the  separation. Gently rock the
       front panel back and forth  horizontally to increase the 
       separation, WITHOUT any forcing.  Do NOT use tools!
9)  When proper separation has been achieved between front  and
       back panels, the top edge may be  separated by gently lifting
       front panel circular plastic  surrounding the headphone jack,
       which will complete the separation of  front and back panels.
       At this point, the back panel may or  may not break off from
       the circuit board, but it is certain  that the dial needle's 
       plastic gear will fall out of its  front panel slot, making you
       think that the radio is  destroyed.  Repeat Step #6 above.
10) Remove back panel from circuit board, if not  already removed
      (simply pull apart the small spot of  glue).
11) Attach battery to contact spring (negative) and clip (positive).
      Tape may be helpful in keeping in the  contacts in place.
12) Turn on radio (center left switch on circuit board), and plug in
13) An RF signal generator is required to verify frequency
      coverage from 520-1750 kHz. If you do not  have one, at 
      least verify coverage from 530-1700 kHz by  checking
      received stations close to these border  frequencies.
14) If an RF signal generator is available, set it to 520 kHz,
      turn the radio's tuner fully CCW, and  peak L3 (the 
      red-slugged can close to the loop stick)  with a non-
      metallic (plastic or wood) flat-bladed  alignment tool
      to obtain loudest headphone volume of the  carrier.
15) If an RF signal generator is available, set it to 1750 kHz,
      set the radio's tuner fully CW, turn the  circuit board over, 
      and peak CT1 (3/4) (the upper right trimming  capacitor
      on the tuner) to obtain loudest headphone  volume of the
      carrier.  This is a sensitive  adjustment.
      NOTE: The frequency coverage has been  perfectly
      set on all seven units as received from  the factory, so 
      lack of a signal generator is not a serious  problem.
16) Turn the circuit board over, and use a very small flat-
      bladed screwdriver to carefully scrape away  all the wax
      bonding the smaller loop stick coil (the one  closest to
      the tuner) to the ferrite bar.  Clear a  slide path on both
      sides of the coil at least .25 inch  long, free of wax, for 
      the next step. Verify freedom of coil to  slide either way.
17) Set RF signal generator to 600 kHz, and set radio tuner
      near 600 kHz (or, if RFsignal generator is  not available,
      use a live WEAK signal near 600 kHz for the  next step).
18) Tune in RF signal generator signal, or the weak live signal
      on or near 600 kHz. Carefully slide  coil along ferrite bar 
      with a NON-metallic (wood, plastic)  probe to peak the
      received signal. Perform this step  repeatedly to find the
      exact spot of strongest, clearest audio  (NOTE: This step
      is the one most important to improve  factory-unit 
19) Secure the small coil to this spot with a piece of tape, or
      small spot of woodworking glue.
20) Turn circuit board over.  Set signal generator to 1400 kHz,
      and set radio tuner to near 1400  ( or, if RF signal 
      generator is not available, use a live  WEAK signal near
      1400 for the next step).
21) Tune in RF signal generator signal, or live weak signal
      near 1400.  Carefully peak CT1 (4/4)  (the upper left 
      trimming capacitor on the tuner) for maximum  clear 
      audio signal.
22) Turn off radio, unplug headphones, disconnect battery.
23) Restore tuner to maximum CCW position, and reinstall
      orange plastic dial linkage in front-panel  slot. As viewed
      from front, place dial needle in the EXACT  spot noted in
      Step #4 above (this is EXTREMELY  important!)
24) Slowly slide circuit board headphone jack under top
      edge of front panel, and very carefully work  the circuit
      board into position adjacent to front panel.  Ensure that 
      battery clips do not bind.
25) Carefully check tuner for bind-free operation. If tuner
      binds, or if tuner frequency does not match  the dial, 
      the circuit board must be removed and dial  linkage 
      repositioned for correction (this is the  trickiest step
      in the alignment).
26) If tuner operation is smooth and frequencies match, you
      have just guaranteed yourself success in  this extremely
      rough alignment!  Congratulate yourself  repeatedly!
27) Carefully reinstall back panel by sliding top edge under
      top edge of front panel, and very gently  (without forcing)
      snap into place, observing slots along sides  and bottom.
28) Reinstall two back screws, battery, headphones, and 
      belt clip.
29) Turn on radio. Log tons of DX.  Call yourself a champion!
73 and Good DX,
Gary DeBock
SRF-59 Tech Trio Junior Member 

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