Preamplifier; Attenuator - Icom IC-i7410 Instruction Manual

5
FUNCTIONS FOR RECEIVE

■ Preamplifier

The preamplifier amplifies weak signals in the receiver
front end, to improve the S/N ratio and sensitivity.
Turn this function ON when receiving weak signals.
➥ Push [P.AMP•ATT] one or more times to set the
preamp OFF, preamp 1 ON or preamp 2 ON.
• Either "P. AMP " or "P. AMP " is displayed when the
preamp 1 or preamp 2 is ON.
• No indicator is displayed when the preamp is OFF.
Wide dynamic range preamplifier. It is
P. AMP
most effective for 1.8 to 21 MHz bands.
High-gain preamplifier. It is most effective
P. AMP
for 24 to 50 MHz bands.

■ Attenuator

The attenuator prevents a desired signal from being
distorted when very strong signals are near the sig-
nal's frequency, or when very strong electromagnetic
fields, such as from broadcast stations are near your
location.
These can both be independently set for each band.
➥ Hold down [P.AMP•ATT] for 1 second to turn ON
the Attenuator.
• "ATT" appears when the Attenuator is ON.
➥ Push [P.AMP•ATT] momentarily to turn OFF it.
About the Preamplifier and Attenuator switching procedure
The Preamplifier and Attenuator are switched with [P.AMP/ATT], as shown below.
55
P.AMP P.AMP P.AMP
OFF
Push
[P.AMP•ATT]
✔ About the "P.AMP2" preamplifier
The preamp 2 is a high gain receive amplifier. When
it is used in the presence of strong electromagnetic
fields, distortion sometimes results. In such cases, use
either the "P.AMP 1" or "P.AMP OFF" setting.
Preamp 2 is most effective when:
• Used on bands above 24 MHz and when signals are
weak.
• Receive sensitivity is insufficient when using low-gain
antennas, or while using a narrow band antenna.
[P.AMP•ATT]
Hold down
ATT ON
Push