Ramsey Electronics SR-1 Instruction Manual page 16

If you like precision, use a frequency counter or calibrated receiver to find the
SR-1's strong oscillator signal, remembering that there is a 260 Khz IF
difference between the local oscillator frequency and the broadcast signal
you are hearing.
Following are results of tests on an SR-1 to give you a general guideline on
what to expect if you want to pre-set adjustments of oscillator coil L2. Each
turn of L2 is one full turn clockwise. Please realize the margin of error from
receiver to receiver in such measurements, due to the manufacturing
tolerances of the capacitors and coils involved. Also, notice how the amount
of frequency change per turn increases with each turn. However, we can see
that a setting of somewhere between 4 and 5 turns might permit tuning of all
three of the major shortwave bands under 10 Megahertz, depending on the
characteristics of your particular varactor diode. A 2.5 Mhz. swing is all that
we can reasonably guarantee.
L2 SETTING
Flush at top of shield
1 turn
2 turns
3 turns
4 turns
5 turns
6 turns
Maximum
OSCILLATOR RANGE
3.94-6.77 Mhz
4.01-6.87 Mhz
4.27-7.31 Mhz
4.77-8.20 Mhz
5.50-9.30 Mhz
6.31-9.83 Mhz
7.10-10.20 Mhz
7.27-10.25 Mhz
SR-1 – 16
TUNING RANGE
3.68-7.03 Mhz
3.75-7.13 Mhz
4.01-7.57 Mhz
4.51-8.46 Mhz
5.24-9.56 Mhz
6.05-10.09 Mhz
6.84-10.46 Mhz
7.01-10.51 Mhz