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What is a VFO? Some sort of spaceship perhaps? |
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VFO stands for Variable Frequency Oscillator. It's an historic
term which really is a misnomer in the context of a Phase Locked Loop (PLL) radio such
as the R20. It derives from the days when radio would either be fixed to a
particular frequency with a crystal, or have a variable frequency oscillator to tune around the
bands with infinitely variable precision. |
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What they call a VFO on a modern synthesised radio like the
R20, is an alterable set of parameters
which are not saved to a memory channel. |
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The settable parameters for a given VFO state are similar to the parameters
that each memory location holds. |
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There are, of course, two independent VFOs
on the R20. Many other receivers boast multiple VFOs but in fact only allow the
user to select one of several sets of VFO parameter values.
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VFO Parameters
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The value of the following parameters can be set before
scanning or listening in VFO mode |
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The activation of VFO mode is denoted by the lack of a memory
channel number showing in the bottom right of the screen |
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Scanning in VFO
mode |
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You can use the VFO mode to scan through the entire spectrum,
a whole band or between two scan edges. |
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In VFO mode, press and keep holding down MODE SCAN and
one of the following will appear |
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Scanning in VFO Mode |
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Displayed |
Notes |
| SCAN : ALL |
Scan the entire extent of
the R20's coverage |
| SCAN : BAND |
Scan the entire extent of
the current band |
| SCAN : PROGxx |
Scan between
pre-programmed scan edges |
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The displayed value can be changed by rotating the tuning knob |
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When MODE SCAN is released, the R20 commences to scan
the selected routine. |
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