COLLINS AT K0DEW



          K0DEW has been collecting and restoring Collins equipment for over twenty-five years, but this old broadcast transmitter turned out to be
          one of the most challenging and interesting.   I had restored a KW-1 and several large military transmitters, so I was ready for this project.
          My goal was to make each and every part like it looked and worked when it moved out the front door of the Collins factory in Dallas TX
          almost  fifty years ago.   I was informed on a Tuesday that the transmitter was going to the land fill on Saturday, so on a Wednesday I loaded
          my pick-up with a few hand tools and a friend, KC0VOB.               
     

Collins 20V-3


                                     This is the way I found the old transmitter at the station in southern Missouri.  The front door was missing
                                     and the transmitter was located against a wall.  Because it was so heavy, and we could not slide it out from
                                     the wall, we removed the entire front panel to get at the heavy iron on the bottom.  All of the hardware was
                                     saved in one container and separated later.                                             




                                    When we got some of the big iron out we could move it from the wall and get to the back doors.  This move let us
                                    remove the other big parts on the bottom shelf.  Shown here are two of the High Voltage Filter Caps and the shelf
                                    for the Modulation Transformer.  The Caps were found to be bad and were replaced.




 
                                     Here is the High Voltage Transformer on the right and one of the Filter Chokes on the left.   All of the wiring and
                                     small parts had to be removed in order for two fellows to get it out of the station.  Even with everything removed the cabinet
                                     weighted at least three hundred pounds.  I think the station was built around the transmitter.






                                                                This close up is of the Modulation Transformer and the dirt on the wiring.





                                     All of the wiring was removed and put in a box for transportation back to the home QTH.  Photos of everything were
                                     taken by KC0VOB, but were of little use putting the old beast back together.  After we got the 20V-3 loaded in the
                                     pick-up  truck we made one last search of the transmitter room and found the front door under a pile of trash.




                                            
                                                 Alter a lot of work and straining of our two backs, we got it home and on the porch of the work  building.
                                                 This is about as close as my wife would let me get the dirt to our house.  The RF box on the left and
                                                 the modulation box on the right was removed before I gave it a bath with soap and water .  The large box
                                                 at the top contains the Pi-L tuning network, it was removed and cleaned separately.
                                                



                                   The RF Deck is on the left and the Modulation Deck on the right.  These fans were not the correct ones for
                                    this transmitter.  Correct ones were added later in the restoration process.  These decks were removed and cleaned
                                    individually.   The rig uses a pair of 4-400s in the Final and a pair in the Modulator.






                                    After each part was cleaned and dried in the sun for several days, each and every part was reinstalled in the cabinet.
                                    The wiring was the hardest to get in its correct place.  When I got the dirt off the wiring the colors changed and with out
                                    the help of Dave, W3CRA, and his wiring photos, rewiring would have been almost impossible.   It took about nine
                                    months to get to this point in the reconstruction.  The large front door had to be repainted along with the two dark
                                    grey doors on each side.   Minor mechanical items needed to be fabricated, painted and installed.  A few modifications
                                    to the electronics had been made by the engineers over the course of fifty years, these were either cleaned up
                                    or removed.  





                                                                                                                  CLEAN-CLEAN-CLEAN





 

 
                                                                                                    N0GW, Gary and K0DEW hard at work.       



Some times it takes four hands, and two brains, to figure out what is needed to make it work.






  I need help finding the RF meter.  This is the only missing part.




THIS IS NOT A 12 VOLT RADIO



This project is a labor of love and is a tribute to the many engineers, technicians and workers at Collins Radio that make
it possible.

My personal thanks to KC0VOB for taking photos all during the project, to N0GW for helping find where the parts of the puzzle went,
to W3CRA for supplying shots of his 20V-3 and encouraging me all the way, and to N7OTQ for his articles on the 20V-3 in the CCA Signal.



 
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