40 Meter Band VFO Kit (for Universal Receiver)

The parts in this VFO Kit are designed for 40 Meter CW reception from approximately 7006 to 7079 KHz
The Kit includes the following parts/items:

L1 FT37-61 20T#27Green
L2 T50-7 44T#28Red
L3 FT37-61 20T#27Green
T1 T37-2 30T#30Red::4T#27Green
C3 100pF NPO marked 101
C6,8 220pF NPO marked 221
C7 47pF NPO marked 470
C10 470pF NPO marked 471
C11 180pF NPO marked 181J
C14,15,16,17 470pF NPO marked 471
C20,21 120pF NPO marked 121
Crystals initially shipped starting March 27,2018 are
X1,2,3,4 Matched 5.0688 (filter center ~ 5,068.9 Khz)
Crystals shipped after July 22, 2018 are
X1,2,3,4 Matched 5.0688 (filter center ~ 5,067.4 Khz)
34 inches Green #27 magnet Wire
35 inches Red #28 magnet Wire
19 inches Red #30 magnet Wire

Install all the below parts in the order given.

_____C3: Install 100pF Capacitor (marked 101)

_____C6,8: Install 220pF caps (marked 221)

_____C7: Install 47pF cap (marked 470) - used to feed Freq Counter

_____C10: Install 470pF cap (marked 471) - part of VFO tune circuit

_____C11: Install 180pF cap (marked 181) - part of VFO tune circuit

_____C12,13: Install two 100n green caps from the base kit

_____C14,15,16,17: Install 470pF capacitors - establish crystal filter bandwidth

_____C20,21: Install 120pF BFO capacitors; because of 0.1 inch lead spacing, install in the left and center holes

Wind and install all Toroid Inductors.  Wind all wires on the toroids clockwise.


_____T1: Install RF Bandpass Transformer.

   Cut 19" of #30 red wire and tightly wind 30 turns on T1, a Red T37-2 toroid
   Cut 6" of #27 green wire and wind 4 turns
   Trim the #30 red wires to one inch.
   Trim the #27 green wires to half inch.

   Tin/solder the wire ends to the base of the toroid using a hot solder pencil.
   Spread the turns over most of the toroid.
   Install T1 with the #30 wires into the outside (upper and lower) holes on the PCB
   and the 3 or 4 turns #27 wire thru the center holes for T1.
   Pull the wires tight on the bottom of the PCB and solder, then trim.
   You should be able to straighten the toroid to match the outline on the PCB.

_____L1: Install Series tuned Inductor

   Cut 14" of #27 green wire and tightly wind 20 turns on L1, a black FT37-61 toroid
   Trim the #27 green wire to one half inch.
   Tin/solder the wire ends to the base of the toroid using a hot solder pencil.
   Spread the turns over most of the toroid.
   Install L1 on the PCB
   Pull the wires tight on the bottom of the PCB and solder, then trim.
   You should be able to straighten the toroid to match the outline on the PCB.

_____L2: Install Main VFO Inductor (use holes A & B) DO NOT INSTALL IF USING A DDS

   Cut 35" of #28 red wire and tightly wind 44 turns on L2, a white T50-7 toroid
   Trim the #28 red wire to one half inch.
   Tin/solder the wire ends to the base of the toroid using a hot solder pencil.
   Spread the turns over most of the toroid.
   Install L2 on the PCB
   Pull the wires tight on the bottom of the PCB and solder, then trim.
   You should be able to straighten the toroid to match the outline on the PCB.

_____L3: Install Series tuned BFO Inductor

   Cut 14" of #27 green wire and tightly wind 20 turns on L3, a black FT37-61 toroid
   Trim the #27 green wire to one half inch.
   Tin/solder the wire ends to the base of the toroid using a hot solder pencil.
   Spread the turns over most of the toroid.
   Install L1 on the PCB
   Pull the wires tight on the bottom of the PCB and solder, then trim.
   You should be able to straighten the toroid to match the outline on the PCB.

_____X1,2,3,4: Install 5.0688 MHz IF Crystals