2 turns primary + 150 pF, 16 turns secondary seems to be good for 40-10m
3 turns primary + 150 pF, 24 turns secondary is good for 80-20m
FT240-43
Primary : 2 t,
LIGHT TWIST
C=150 pF Rtest = 3,1 kΩ
3510 kHz
|
7029 kHz
|
10140 kHz
|
14016 kHz
|
18096 kHz
|
21054 kHz
|
24930 kHz
|
28041 kHz
|
SWR = 2,61
|
SWR = 1,33
|
SWR = 1,11
|
SWR = 1,28
|
SWR = 1,41
|
SWR = 1,39
|
SWR = 1,30
|
SWR = 1,44
|
FT240-43
Primary : 3 t,
Secondary : 34 t
TIGHT TWIST
C=150 pF Rtest = 3,1 kΩ
3510 kHz
|
7029 kHz
|
10140 kHz
|
14016 kHz
|
18096 kHz
|
21054 kHz
|
24930 kHz
|
28041 kHz
|
SWR = 1,57
|
SWR = 1,29
|
SWR = 1,33
|
SWR = 1,65
|
SWR = 2,46
|
SWR = 3,85
|
SWR = 7,14
|
SWR = 13,63
|
Construction of 40-10m transformer
The plastic box is G311 (IP65)
Ref Farnell 1094700 price< 8 €
Ready for real test with End Fed
