Sb: MODIFICATION OF TS-450SAT
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[  GENERAL COVERAGE TRANSMISSION MODIFICATION FOR THE TS-450 AND TS-690      [

[  DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD     [

[  A) Remove all screws of top and bottom case.                              [

[                                                                            [

[  B) Remove two screws of front panel (left and right top side),and loosen  [

[     two screws of front panel (left and right bottom side).  Now gently    [

[     pull out the front panel about a quarter inch and then tilt it down,   [

[     so you can get to the digital unit board located behind the panel.     [

[                                                                            [

[  C) Remove all screws of digital/PLL unit (X46-312X-XX or X50-3150-xx).    [

[     Gently unplug the connectors at the top of the board so that you can   [

[     rotate it forward to get to D27 (see E below) which is on the rear of  [

[     the board.                                                             [

[                                                                            [

[  D) Cut the chip diode D21 (RL73) on digital unit front side for 30-40 mHz [

[     receive only (no transmit).  WARNING: if you cut this diode, though,   [

[     you will decrease maximum output power from 27.5 to 30 mHz by half to  [

[     a maximum of 50 watts (!) and FM on all bands to a maximum of just     [

[     10 watts (!)É so I don't recommend this diode be cut, even though      [

[     it can be done and it's easy to get toÉ There's nothing much worth     [

[     listening to between 30 and 40 mHz anyway.                             [

[                                                                            [

[  E) Cut the chip diode D27 (RL73) on digital unit rear side for general    [

[     coverage (1.620 to 29.999 mHz) transmit.  (If you decide to do the     [

[     30-40 mHz receive mod described in D above, you still wonÕt be able to [

[     transmit 30-40 mHz by clipping diode D27, by the way.)  I recommend    [

[     this mod, even though the diode is sometough tough to get to.          [

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[  [  \_ Bat. _\                                          [                  [

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[  [    [_\_[     [   [        [          [               [                  [

[  [    [   [     [ \ [        [          [      ->I- D27 [ <---GEN CVG      [

[  [    [   [     __ __        [\\\\\\\\\\_      ->I- D26 [                  [

[  [    [\\\[                                    ->I- D25 [                  [

[  [                                             ->I- D24 [                  [

[  [                                             ->I- D23 [                  [

[  [                                             ->I- D22 [                  [

[  [                                             ->I- D21 [ <---30-40 mHz rx [

[  [                                             ->I- D20 [                  [

[  ________________________________________________________                  [

[      DIGITAL JNIT (X46-312X-XX)     Component side view                    [

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[  These modifications are at your risk.                                     [

[                                                                            [

[  Clipping D27 is recommended for both the TS450S and TS690S.  However,     [

[  clipping D21 is not recommended (see ÒDÓ above) since it decreases output [

[  power on 10 meters as well as enabling 30-40 mHz receive!!!  (Keep in     [

[  mind that this is unnecessary AND ill advised on the TS690S since it      [

[  already receives continuous to 60 mHz.                                    [

[                                                       -- WA4FJF            [

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