Vectronics VEC-1120K - Manual (Page 27)

VEC-1120K/1130K/1140K/1180K Instruction Manual
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or inserted into the coil. You will have to adjust the coil in small
increments, and observe the point where the proper frequency is
reached when the tool is removed.
FINAL ALIGNMENT
Once the tuning range is set, the RF input stage must be peaked for best
sensitivity. This can be done using a signal generator, or on-the-air signals.
Find an alignment tool or jeweler’s screwdriver that fits trimmer capacitor C18.
Use one of the following three methods to peak C18.
! 1. Using a signal generator, peak C18 for best sensitivity. Reduce the
signal generator output, or reduce the R1 Gain control setting, to prevent
overload as C18 is brought into resonance.
! 2. Using off-air signals, adjust C18 until signals are loudest. Reduce the R1
Gain control as C18 is brought into resonance to prevent overload.
Verify that C18 is properly peaked while monitoring a known on-air
signal.
! 3. With an outside antenna connected, peak C18 for maximum atmospheric
noise in the headphones or speaker. Verify that C18 is properly peaked
while monitoring a known on-air signal.