Someone was curious about the voltage-to-
frequency curve for the 38s. Now, understand
that everyone's will be different, depending
on how much the xtal swings, which choke
value is in series, and the 1N4004 'varicap'
capacitance range.
With that caveat, here's the data
from my rig, with a 6.8uh choke installed
for L1. The pot is a linear-taper RV4 type
that's suppose to rotate 313 degrees.
volts freq-10Mhz potAngle
0 0.09288 0
0.0065 0.093 15
0.031 0.094 25
0.084 0.096 30
0.142 0.098 34.7
0.206 0.1 36.7
0.28 0.102 41
0.36 0.104 44.6
0.45 0.106 48
0.56 0.108 52
0.68 0.11 56.8
0.81 0.112 62.6
0.97 0.114 74.3
1.18 0.116 82.8
1.43 0.118 90
1.79 0.12 96
2.04 0.121 104
2.34 0.122 114
2.71 0.123 126
3.19 0.124 139
3.75 0.125 157.5
4.42 0.126 182
5.3 0.127 207.2
6.38 0.128 233.2
7 0.1285 251
7.7 0.129 274
8.02 0.12922 292
8.05 0.12923 313.5
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