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Maintenance & Troubleshooting
Advanced Troubleshooting
If the picture regularly breaks up, then the signal received may be too weak or too strong to
allow the digital TV receiver to generate a stable picture.
Have your service provider confirm that the signal level at the machine is 72 dBuV + / - 25 dB.
This is equivalent to +12 dBmV, and includes the range of -13 dBmV to +37dBmV. These levels are
acceptable for both analog and digital TV signals.
If signal levels are not OK, you are unlikely to have good reception unless signal strength can be
improved - antenna relocation or changes to your amplifiers (masthead or distribution) may be
indicated.
Remember amplifiers should only be used by your installer to provide the minimum necessary
boost to signal strength.
Interference from impulse noise may be causing pictures to break up and audio to drop out
momentarily.
Check for domestic sources of impulse noise (i.e. the use of light switches, fridges, hair dryers, air
conditioner, etc.).
If present, arrange for all cables, connectors, outlets and splitters between the antenna and the
receiver to be upgraded in accordance with antenna installation guidelines. Recommends the use
of quad shielded coaxial cable and F connectors.
A masthead amplifier may have boosted the signal outside the receiver’s “operating win-
dow”, making reception impossible.
The masthead amplifier (appears as a small box on the antenna pole within about a meter of the
antenna arms) may be able to be turned down - if your antenna is on your roof you should arrange
for an antenna installer to perform this task.
When digital broadcasting services begin operating in an area some masthead amplifiers (boost-
ers) operating at maximum output or maximum gain may need to be turned down to avoid signal
overload for digital receivers. This matter should be determined by an antenna installer, who will
be able to adjust the amplifier for you.
Please note that performing this operation may affect any existing analog signals, so you
MAY
need to find a medium point between adequate analog reception and good digital reception.
