FM TRANSMITTER
TR
EM
1000
HE
DIG
PLUS
COMPACT
Technical Manual 1v2 November 2019
60
2.5 Troubleshooting.
All instructions set in this manual are followed, the EM 1000 HE DIG PLUS COMPACT series
will guarantee several years of perfect service. However, should problems arise, refer to this
chapter before contacting the local authorized assistance point.
2.5.1 Error messages
The following table explains the meaning of the main error messages and indicates the actions
to be taken in order to solve the problem.
All alarms will be usually shown in any screen you are, and they will be overlapped on the
upper screen section, where you normally see the company logo, system temperature and
system time. In addition, the
ALARM
LED will light.
The messages below may appear during the amplifier normal operation as well as when the
alarm data are displayed in the
VIEW LOG
sub-menu.
- Mpx low (insufficient modulation)
The
Mpx low
alarm message appears when an insufficient modulation lasts for more than a
given time. Both alarm delay and alarm threshold can be set in the alarms menu, respectively
up to 180 seconds and < -16dB (as to 75KHz frequency deviation, that is 0dB = 75KHz).
- Refl Power High (excessive reflected power)
The
Refl Power high
alarm message appears when the reflected power level exceeds a
threshold, usually set in the range from 5% to 7% of the maximum nominal power level. The
threshold level can be adjusted via the alarms menu.
If necessary, the maximum reflected power level can be automatically limited to the ~ 10% of
the maximum output power level reducing the direct output power.
- Over temperature
The
Over temperature
alarm may be referred to a system over temperature (CPU Temp.) or
only to a RF power stage over temperature (RF temp.); each of the said temperatures is taken
via a specific heat probe.
Before reaching the max allowed temperature, the alarm LED starts flashing, to signalize the
approach to the limit condition. If the threshold is exceeded, the alarm LED stops flashing and
starts steadily lighting. In this condition the output power level will be progressively reduced,
to limit dissipation without completely blocking the transmitter operation.
To check whether the over temperature is due to whole system or to the RF power stage only,
select the
Temperat.
sub-menu, in the
View
menu, which displays both the temperatures:
CPU temp.
= system temperature
RF temp.
= RF power stage temperature
