Atlas 210x, Installation, Operation And Maintenance Manual

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2.33. FIXED STATION ANTENNAS
On 10, 15, and 20 meters a doublet and most beam antennas will match quite well across the entire band. On 40
meters a doublet tuned for phone band center will match quite well across the band. On 75 meters the average
doublet will have a bandwidth of about 100 kc for SWR of 1.5 or less. To work the entire band with full efficiency
will require an antenna tuner. On 160 meters an antenna tuner, or at least some kind of matching system will be
essential, since even at resonance it is unlikely that the feed point will be near 52 ohms. In any case, it is always
best to optimize the antenna system for the frequency where you do most of your operating.
2.34. ANTENNA TUNER OR. "MATCH BOX." An antenna tuner can be a very useful device to compensate for
antenna mismatch. This may be especially true if you happen to have a favorite antenna that has been working just
fine with the old tube rig, and now you discover the new solid state rig doesn't like the old antenna. Refer to the
antenna handbooks for helpful data, or ask your dealer about antenna tuners now on the market.
Figure 2-6. Model 220-CS/200-PS Schematic
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