LDG AT-200Pro Manual - page 18
18
When to use Peak mode
Any averaging wattmeter will read correctly only when excited by a steady, unmodulated carrier.
Any modulation will cause the reading to vary. Peak mode measures the peak power as the name
indicates, and is much steadier in the presence of modulated highs and lows. You will generally
want to use Peak mode when using SSB or AM, and average mode when using FM, RTTY or any
other 100% duty cycle mode that provides a steady carrier to the wattmeter circuitry.
When to turn the LEDs off
You can set the LEDs to remain off when transmitting. This will help conserve power when
operating from batteries (Field Day, for instance), or when you don't want the distraction of the
flashing LEDs.
RF Noise
The processor in your AT-200Pro creates a certain about of RF noise, which you may notice in
your receiver while tuning (only if you are using a separate receiver and not a transceiver) or
when information is being displayed in the LED display. This will be most noticeable when
operating CW with break-in, while using the Peak power display. This should present no
problem, as the Peak mode is not very useful on CW. The extremely short tuning cycle
minimizes the impact of the noise; the tuner creates no RF noise while not tuning.
MARS/CAP coverage
Your AT-200Pro provides tuning continuously over its specified range, not just in the ham bands.
This makes it useful for MARS or CAP operation, or any other legal HF operation.
Error indications
There are four error states that are indicated on the Power LED display by all LEDs flashing
twice:
1. No RF is present when a tune command is executed. So, if you press and hold
Tune
for a full
tuning cycle, but no RF is present, the LEDs will flash.
2. RF removed during a tune. If you stop transmitting during a tuning cycle, the LEDs will
flash.
3. Full tune below Auto tune threshold. If you start a full tuning cycle when the SWR is already
below the Auto tune threshold, the LEDs will flash.
4. Reading
over-range.
To correct error conditions 1 or 2, simply provide RF for the duration of the tuning cycle. Error
condition 3 indicates that a tune cycle is not needed. Error condition 4 indicates power or SWR
beyond the range of the meters.