Technical information

jumpers over to the alternate position; this will bypass the broadcast
filter and enable reception.
The broadcast filter is designed to reject any broadcast station that
may be in the vicinity of the receiving station using the SG-2020
that could cause interference. In some cases, the rejection may not
be sufficient and may be heard in the SG-2020 receiver. Stations
using 100 kilowatts within 10 miles may cause excessive interfer-
ence.
15.2 ADJUSTING THE HIGH PASS ELLIPTICAL FILTERS
Broadcast stations causing excessive interference may be tuned out
by adjusting the resonance point of the SG-2020’s high pass ellipti-
cal filters. Two resonances with rejection better than 50 db are
available and can be tuned directly on the interfering station to sup-
press the unwanted signal.
L1 of the filter is normally adjusted for a dip at 700 kHz. L2 is nor-
mally adjusted for a dip at 1200 kHz (see XMTR PCB ASSY
schematics for location). Adjust the coil nearest in frequency to the
interfering station until the interference is reduced below the noise
level. Tuning will normally go through a dip in audio level.
32
SGC Inc. SGC Building, 13737 S.E. 26th St. Bellevue, WA. 98005 USA
P.O.Box 3526, 98009 Fax: [phone] or 746-7173 Tel: [phone] or 1-800-259 7331
E-mail: [e-mail] Web site: http://www.sgcworld.com
© 1998 SGC Inc
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