Adcom GTP-600 - Manual (Page 10)

window. Tune to an FM station. Extend the top of the “T” antenna and rotate it to the position that results in the
best reception. Once you’ve determined that, fasten the antenna to the wall, a cabinet back or even the ceiling so
that the 'T” is aligned as closely as possible to the direction that gave you the best reception.
Remember that the dipole antenna is directional — it is most sensitive to signals arriving at right angles to the
extended “T” and relatively insensitive to signals arriving from the ends of the "T.”
The dipole antenna rapidly looses its effectiveness when rolled up or carelessly dropped behind a cabinet, etc. If
the “T” antenna is undesirable from a functional or decor point of view, your ADCOM dealer will be pleased to
show you a variety of indoor antennas that might be more appropriate. We do suggest, however, that you ask for
a home trial as reception conditions vary enormously from location to location.
The GTP-600 can also be used with a 75 ohm antenna. These are usually large roof mounted antennas and can
provide superior reception when compared to the 300 ohm “dipole.” In addition, most cable companies use 75
ohm cable to distribute FM signals. Connect the GTP-600 to a 75 ohm antenna system by terminating the
connecting cable with an “F” connector (available at most electronic parts stores) and attaching it to the rear
panel
75 ohm antenna terminal ©.
The grounding schemes used by cable companies are very complex and occasionally cause hum when the
cable is attached to the 75 ohm antenna input. An isolation transformer (again, available at most electronic parts
stores) will usually solve the problem.
5) AM ANTENNA; The supplied movable ferrite "loop” will provide reasonable AM reception in most locations. The
loop should be rotated away from the body of the GTP-600 and some experimentation will undoubtedly improve
AM reception.
In the event that you need better reception, you can make your own AM antenna from a single length of insulated
wire. Connect one end of the wire to the terminal marked “AM" and run the other end to a high location in your
home or hang it from a window.
In most cases, a second wire run from the “Ground" terminal to a solid earth ground (a cold water pipe for
example) will also improve AM reception as well as provide a safe “path to ground” in the event that lightning
strikes an outdoor AM antenna.
6) AUDIO SOURCE HOOK UP; Patience and common sense will help you avoid almost all the errors you might
make when rushing the initial installation. Remember to connect Left Channel to Left Channel and Right Channel
to Right Channel, etc. The jacks on all ADCOM products follow conventional color coding; White for Left Channel
and red for Right Channel. Most interconnect cables observe this general guideline: the connectors on each end
of the cable are usually color coded.
We've received many questions about the sonic attributes of premium interconnect cables. We do suggest
that you make sure any cable you use is a “low capacitance” design. (Most are.) Your ADCOM salesperson
will be happy to make cost-effective recommendations based on individual component characteristics and
system complexity.