Conserving Power When Operating On Batteries; Internally Generated Rf Noise; Mars/Cap Coverage; Theory Of Operation - LDG AT-100ProII Operation Manual

built-in SWR meter will show the tuner's progress. Remember to keep your eyes on the road,
however! In most cases, a match will be recalled from memory, so the SWR will snap to a low
value as soon as you begin to transmit.

Conserving Power When Operating on Batteries

The AT-100ProII is designed with portable operation in mind. The internal relays are
latching-type relays, which mean they only consume power when switching. When the AT-
100ProII is idle, very little current is drawn.

Internally Generated RF Noise

The AT-100ProII is microprocessor controlled, and as such, generates a small amount of RF
noise when the processor is active. Normally, the processor is only active during transmit
operation, so the noise is not normally heard; however, if Peak mode is selected, the processor
remains active for a moment after key-up, to allow the LEDs to settle back down to zero. You
may briefly hear some noise in your receiver during this time. This is normal, and is noticeable
the most when using CW in full break-in, with Peak mode selected. In practice, this should not
be much of a problem, as Peak mode is not very useful when using CW.

MARS/CAP Coverage

The AT-100ProII provides continuous tuning coverage from 1.8 MHz to 54.0 MHz, not just
inside the ham bands. This makes it useful for MARS or CAP operation, or any other legal HF
operation.

THEORY OF OPERATION

Some basic ideas about impedance

The theory underlying antennas and transmission lines is fairly complex, and in fact employs
a mathematical notation called "complex numbers" that have "real" and "imaginary" parts. It is
beyond the scope of this manual to present a tutorial on this subject
help in understanding what the AT-100ProII is doing, and how it does it.
In simple DC circuits, the wire resists current flow, converting some of it into heat. The
relationship between voltage, current, and resistance is described by the elegant and well-known
3 For a very comp let e treat men t of this subject, see any edit ion of th e ARRL Handb ook for Radio Comm uni cati ons (previousl y the Ha nd boo k For Radio Amateu rs).
3
, but a little background will
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