[Elecraft] K1 160 meter modification

[Don Wilhelm]

Chuck,

Here are my original instructions:

 > Not quite a full "Elecraft" 160m & 80m board, but you can do it this 
way -
 > order a 2 band board for 80m and any other band, PLUS, order the 
following
 > components (Elecraft has them all except the crystal) - here are the
 > instructions for how I did it: --
 > maybe you can make a deal with someone at Elecraft to ship a ''1 band 
board
 > and the other needed parts"
 >
 > I ordered the following from Elecraft:
 >
 > Capacitors:
 > 2 - E530002  1500 pf capacitor
 > 3 - E530003  2700 pf capacitor
 > 2 - E530005  1200 pf capacitor
 > 2 - E530035  1800 pf capacitor
 > 2 - E530052   560 pf capacitor
 > 2 - E530053   680 pf capacitor
 > 1 - E530058    12 pf capacitor
 >
 > Inductors:
 > 1 - E690007   33 uh inductor
 > 2 - E690001  4.7 uh variable inductor (wide tuning slot)
 >
 > Toroid cores:
 > 2 - E680001  T44-1 or T50-1 toroid cores (blue color)
 >
 > I also ordered a 9.800 mHz crystal (HC-49 case 20 pf load 
capacitance) from
 > International Crystal Manufacturing www.icmfg.com.
 >
 > If you are planning to use the K1 ATU with this board, you should 
also order
 > the P1 (3 pin) and P2 (10 pin - 5 x 2) headers from Elecraft.
 >
 > The parts from Elecraft (without the headers) were less than $15 and the
 > crystal was priced at $17.95 - not an unreasonable price IMHO.
 >
 > I assembled the 2 band board with the 80 meter components in the band 2
 > locations as indicated in the instructions - except for L5 and L6 
were left
 > empty at this time.
 >
 > Next, the low- pass toroids were wound with 21 turns (20 inches of 
wire) on
 > the T50-1 (blue) cores, and soldered into the L9 and L10 positions.
 >
 > The 4.7 uH variable inductors were soldered in the positions for L5 
and L6.
 > On the bottom of the board, 1200 pf capacitors were soldered across 
L5 and
 > L6 (the outer pins on the side of the can with 3 pins).
 >
 > The 33 uH inductor goes into the position marked for C13.  Form the leads
 > under the inductor body so that the leads fit into the holes - my 
inductor
 > is parallel with the board and tucked between the bandpass filter cans.
 >
 > Mount the 9.8 mHz crystal at the X1 position and solder the grounding 
wire
 > to the side of the can (or top if you prefer).
 >
 > The remaining capacitors are fitted into the following positions:
 > C1 & C5 - 680 pf
 > C2 & C4 - 2700 pf
 > C3           - 12 pf
 >
 > C11 & C15 - 1800 pf
 > C12 & C14 - 560 pf
 > C21 & C23 - 1500 pf
 > C22            - 2700 pf
 >
 > You should now have all the holes filled, and can proceed to align the 2
 > band board following the instructions in the K1 manual.  Mine came up 
with
 > no trouble at all.

73,
Don W3FPR


Chuck Gehring wrote:
> I am looking for instructions to build or modify a KFL1-2 filter board for
> 160 meter operations.
> 
> 73 K2CG
> 
> Chuck G.