Table of Contents
Advertisement
AR3030 operating manual
Aerial Tuning Units (ATU)
An ATU can improve the selectivity of any shortwave receiver when connected
to long wire aerial other than a short wire of a few metres. This valuable extra
selectivity is created provided by the ATU rejecting out of band signals enabling
the receiver to "single out" one band of frequencies while rejecting potentially
strong unwanted transmissions.
An ATU is usually constructed in a small box with about two or three controls on
the front panel. One disadvantage however is the need to constantly retune the
ATU when changing frequency. An ATU of this type has no active circuitry so is
known as a passive device.
Active desk-top loop aerials
Usually designed for the shortwave bands (such as the AOR LA320. Loop
aerials have the advantage of small size when compared to long wire aerials
and being within easy reach of the operator it can be rotated to provide
directivity. The circuitry offers a small level of gain with the advantage of
selectivity similar to an ATU.
* For further information please refer to section 10 of this manual regarding
aerial and earth systems.
(5) Controls and functions
The AR3030 receiver is housed in a strong metal cabinet. Controls for
operation are located on the top and front of the cabinet with connections to the
rear.
Front panel
5-1 On/Off power switch
This square shaped black plastic button switches the set O/Off when running
from an external power supply or internal batteries.
To switch the set On, connect a suitable power source and depress the switch,
it will latch in.
To switch the receiver Off press the switch a second time, the switch will latch
out.
10
Advertisement
Table of Contents
