2304 MHz mods: Up Converter, Harris SD-97332 (Farinon division)

Le dernier étage doit être contourné puisqu'un signal d'attaque plus que suffisant est obtenu du radio IF via la plaquette DEMI.

The last amplification stage will be disabled as plenty of drive is available from the IF radio through the DEMI TC board.

Photos

Précautions, électricité statique

ESD rules in effect !

Electrostatic Sensitive Devices (ESD)

Field Effect Transistors (FET) in this module can be destroyed by static discharges.

  • Take applicable precautions:
    • Always touch chassis first, before touching anything inside the module.
    • Ensure your soldering station is "ESD safe".
Notes about soldering at Elecraft.

Premières étapes

Photo #
Three cuts to be done.

Preparations

  • A) Cut trace at "A": the last gain stage is not used.
  • B) Lift (unsolder) the end of the choke from the pad where it meets with 2 other coils.
  • C) Remove the output FET. Cutters with fine tips will do the job nicely. The FET will not be reused.

Dérivation du dernier étage

Photo #
Keep that bridge flat and very short! Bypass the last stage.

Replace last FET by conductive bridge

  • D) Solder a fine copper foil strip across the input and output traces of the last stage.
    • Make the strip as short as possible, otherwise glue residue may remain trapped underneath.
    • Inductance grows rapidly with any excess length at 2.3 GHz !
    • Keep the strip about the same width as the traces it bridges.
    • Remove any remnant of the former FET legs before positionning the bridge.
    • Ensure it does not touch the upper and lower traces that fed the FET originally.

Ré-assemblage du module

 

Closing up

  • Verify that the choke you lifted will not touch the cover upon closure.
  • Put the cover back and re-install the module in the transverter box.



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