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WaLowFer (Wanjina Mode for LF Experimentation)

A LF Version of Wanjina (a.k.a. FDK)

General Philosophy of WaLowFer:-

Having had success with a HF version of Wanjina (WaHifer) in crossing the Pacific (Sydney, Australia to the US & Canada) using 2mW - 8mW on 13.555450MHz, I have returned to experimenting with a version for LowFer work. Prior experimentation was hindered by the absence of stations with sufficient stability and accuracy - now this is becoming commonplace.

Method of Generation:-

The linear method of generation seems to be an obstacle for many stations, so a non-linear method is considered. The use of soundcards for generation of signals is the most elegant but requires a linear amplifier which results in large amounts of dissipation at high powers. To generate a very narrowband version of Wanjina for LF a simple phase-switching method was utilised. The hardware to do this is simply an XOR gate with one input driven by the carrier wave and the other driven by the phase control signal.

WaLowFer Wanjina Protocol:-

There are several schemes under consideration. One is simply a narrowband version of WaHiFer, the other is a simple progression scheme of timing of phase shift as follows which is for 120 second dots:-

Character
Phase Reversals
Time Between Reversals
Difference Frequency
Space
4
30.000
0.067
A
5
24.000
0.083
B
6
20.00
0.100
C
7
17.143
0.117
D
8
15.000
0.133
E
9
13.333
0.150
F
10
12.000
0.167
G
11
10.909
0.183
H
12
10.000
0.200
I
13
9.231
0.217
J
14
8.571
0.233
K
15
8.000
0.250
L
16
7.500
0.267
M
17
7.059
0.283
N
18
6.67
0.300
O
19
6.316
0.317
P
20
6.000
0.333
Q
21
5.714
0.350
R
22
5.455
0.367
S
23
5.217
0.383
T
24
5.000
0.400
U
25
4.800
0.417
V
26
4.615
0.433
W
27
4.444
0.450
X
28
4.286
0.467
Y
29
4.138
0.483
Z
30
4.000
0.500
0
31
3.871
0.517
1
32
3.750
0.533
2
33
3.636
0.550
3
34
3.529
0.567
4
35
3.429
0.583
5
36
3.333
0.600
6
37
3.243
0.617
7
38
3.158
0.633
8
39
3.077
0.650
9
40
3.000
0.667