Figure 7:
Parts mounted on bottom of board
Several parts mount on the bottom of the board. These are the variable capacitors, the toroid coils, the BFO
trimmer and the resetable fuse.
Table 5
CV1, 2, 3
Mount these three variable caps to the bottom of the board, using the short screws supplied.
CT1
BFO trimmer. Make sure the flat side of the cap faces the line in the part outline, towards the
top edge of the board.
Fuse
The outline is shown on the top side, but is mounted on the bottom.
Winding the toroids:
The wire needs to be wound snug to the core. A loose, sloppy winding job will result in poor performance. A turn
is each time the wire passes through the center of the core. Miss counting and having an extra turn is a common
mistake and will result in low power output.
Make sure you tin the wire leads before trying to solder the wire to the board! And make sure you don't pull the
wire through the pad past the tinned area of the lead. You can tin with your iron with a blob of solder at the
tip.
Table 6a:
L6 – L14
L6
18 turns #28 (11”) on T37-2, Red core
40M
L7
21 turns #28 (12.5”) on T37-2, Red core
40M
L8
13 turns #28 (9”) on T37-2, Red core
30M
L9
18 turns #28 (11”) on T37-2, Red core
30M
L10
14 turns #28 (9”) on T37-6, Yellow core
20M
L11
18 turns #28 (11”) on T37-6, Yellow core 20M
L13
40 turns #28 (22”) on T37-2, Red core
Rx in
L14
40 turns #28 (22”) on T37-2, Red core
Rx in
