Operating Instructions; Getting To Know Your At-1000 - LDG AT-1000 Manual

Operating Instructions

Getting to know your AT-1000

Your AT-1000 is a quality, precision instrument that will give you many years of outstanding service; take
a few minutes to get to know it. On the front panel, there are six pushbutton switches:
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Power: turns your AT-1000 on and off
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Manual capacity and inductance adjustments (rarely needed)
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Ind Up: adds inductance
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Ind Dn: subtracts inductance
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Cap Up: adds capacity
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Cap Dn: subtracts capacity
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Tune: begins a tuning cycle, places the tuner in bypass mode
The Power switch does not turn the tuner completely off. It places it in a low-current "sleep" mode. In the
Off mode, the tuner is in bypass, routing RF directly from your amplifier to the antenna with no matching.
On power-up, the tuner is automatically restored to the last tuned setting. If DC power is interrupted, the
tuner will revert to bypass mode on power-up.
In addition to the pushbuttons, there is a cross-needle meter. This meter indicates forward power up to
1,000 watts, reflected power up to 180 watts and SWR (see Theory of Operation, below). Power readings
are accurate to +/- 5% of full scale across the entire range (this may very well be the most accurate
wattmeter you own!). This meter also indicates various operational states, as described later in this section.
Forward and reflected power are indicted on individual scales. SWR is read at the intersection of the two
needles, on the curved red scales across the center of the meter face. In the picture below, the meter is
indicating forward power of 100 watts, reflected power of 11 watts and an SWR of 2.0.
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