CONVENIENCE FEATURES

IPO (INTERCEPT POINT OPTIMIZATION)

The IPO feature allows the operator to optimize the characteristics of the receiver front end, depending on the current noise level and the strength of incoming signals.

Press the [IPO] button several times to set the desired characteristic of the receiver front end, per the chart below.

AMP1: Amplifies the incoming signal path using a low distortion RF preamplifier (gain: approx. 10 dB).

AMP2: Amplifies incoming signal path using a 2- stage low-distortion RF preamplifier (total gain: approx. 17 dB).

ON: Bypasses the RF preamplifier, yielding direct feed to the first mixer.

The selected receiver RF preamplifier will be indicated in the IPO column of the Receiver Configuration Indicator on the display.

ADVICE:

Receiver Configuration Indicator

[IPO] Button

AMP1

AMP

AMP2 AMP

ON

On the 10 MHz and lower bands, it generally is not necessary to use any preamplifier at all; selecting the “ON” position described above will increase the strong-signal-handling capability of the receiver, and generally will result in more pleasant reception due to reduced noise. If you can hear band noise with the preamplifiers disengaged, then a preamplifier is generally not needed.

ATT

Even with the IPO function on, extremely strong local signals or high noise can still degrade reception. In such situations, you can use the [ATT] button to insert 6, 12, or 18-dB of RF attenuation in front of the RF amplifier.

1.Press the [ATT] button several times to set

the desired attenuation level, per the chart below.

OFF: Attenuator is Off

–6 dB: The incoming signal power is reduced by 6 dB (Signal voltage reduced by 1/2)

–12 dB: The incoming signal power is reduced by 12 dB (Signal voltage reduced by 1/4)

–18 dB: The incoming signal power is reduced by 18 dB (Signal voltage reduced by 1/8)

The selected attenuation level will be indicated in the ATT column of the Receiver Configuration Indicator on the display.

Receiver Configuration Indicator

[ATT] Button

2.To restore full signal strength through the Attenuator circuit area, press the [ATT] button to restore the ATT display to the “OFF” position.

ADVICE:

￿The Attenuator affects both the Main (VFO-A) and Sub (VFO-B) bands.

￿If background noise causes the S-meter to deflect on clear frequencies, press the [ATT] button until the S-meter drops to about “S-1.” This setting optimizes the trade-offs between sensitivity, noise, and interference immunity.Also, once you have tuned in a station you want to work, you may want to reduce sensitivity further (or add more attenuation) by pressing the [ATT] button to a more setting. This reduces the strength of all signals (and noise) and can make reception more comfort- able, important especially during long QSOs. When looking for weak signals on a quiet band, you will want maximum sensitivity, so the IPO should be disabled and the [ATT] button should be set to “OFF.” This situation is typical during quiet times on frequencies above 21 MHz, and when using a small or negative-gain receiving antenna on other bands.

FT-2000 OPERATING MANUAL

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