Vectronics VEC-101K - Manual (Page 19)

VEC-101K Owner's Manual Shortwave Converter Kit
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2. Connect the signal generator output to RCA jack J1 on the VEC-201. Use
coaxial cable with suitable connectors or adapters.
3. .Connect the receiver antenna connector to RCA jack J2 on the VEC201.
Use coaxial cable with suitable connectors or adapters.
4. Set the converter bandswitch to the “in” position (low frequency band).
5. Set the receiver to the frequency corresponding to the lowest portion of the
Shortwave band being calibrated (i.e.: 900kHz for 3900kHz on the 75-
Meter band).
6. Attach a battery and turn on the converter.
7. Carefully adjust capacitor C13 until the signal generator signal is heard on
the receiver.
8. Increase the signal generator frequency slightly (20 or 30 kHz) and note in
which direction the receiver has to be retuned to find it. If the receiver has
to be set lower in frequency to find the signal generator, the Local Oscillator
has been set for high-side injection. Continue with the alignment until the
proper low-side injection Local Oscillator setting is found.
9. Repeat the above steps to adjust the Local Oscillator on the higher
frequency band. Remember to set the bandswitch to the extended position.
Capacitor C12 is used to set the high-frequency band Local Oscillator
frequency. Set the receiver dial to correspond to the new band’s lower edge.
Set the signal generator to the new frequency.
Performing Antenna Trimmer Alignment:
The objective is to peak ceramic trimmer C10 for best signal reception on the
high- frequency band, and ceramic trimmer C11 for best signal reception on the
low-frequency band. The trimmers are peaked for best reception at the
approximate center of the band of interest. For example, for 41 Meters (7.10 to
7.30 MHz) the antenna trimmer would be tuned for maximum response at 7.165
MHz.
Using off-air signals: Once the Local Oscillators are set to frequency, antenna
trimmers C10 and C11 may be peaked for best reception. Tune into a weak
shortwave broadcaster, and peak the associated antenna trimmer for best volume.
On the lower shortwave bands, the trimmers can often be peaked for maximum
noise. It is possible to tune the trimmers to an image response, so be sure the
signal you’re peaking to is operating in the desired band!
Using a signal generator: Use the same basic setup suggested for the Local
Oscillator alignment with a signal generator. The signal generator is set to the
center of the desired shortwave band, and the receiver is tuned to the generator