Model: MC-1-DE
Doc Ref. No:-m05dom102
Issue No:-00
Page 23 of 76
User’s Manual
6.1.3 Verifying Antenna and Cable Operation
Please ensure that while doing below mentioned procedure
for checking antenna voltage/current while unit is in POWER
ON condition, do not short the antenna supply +5 Vdc and
GND, in any case, failure of which will damage the unit in-
ternal electrical supply.
This equipment is sensitive to Electrostatic Discharge
(ESD). Observe all ESD safeguards while using this equip-
ment. Otherwise, there is danger that the unit may get dam-
aged through ESD.
6.1.3.1 Checking the Antenna Voltage
GPS TIME SYNC UNIT MC-1-DE unit pr5 Vdc to the GPS antenna though its Antenna con-
nector on unit front panel, which is carried through the antenna cable. Nominal antenna current is 10
mA. Check the voltage at the antenna connector on the unit rear panel antenna connector. Without
the +5Vdc supply on antenna connector of unit, the antenna and GPS TIME SYNC UNIT MC-1-DE
will not synchronize with the GPS satellites signal and can generate an GPS UNLOCK alarm.
6.1.3.2 Power
Supply Check
The Antenna Voltage test (mentioned above in section 6.1.3.1) actually tests the main power supply
voltage for all models of GPS TIME SYNC UNIT MC-1-DE’s. This voltage should be between 4.7 and
5.0 Vdc.
6.1.3.3 Checking the Antenna Resistance
Checking the internal resistance of the GPS antenna is not as useful as verifying the antenna current
mentioned above in section 6.1.3.1. Antenna resistance measures several mega ohms with Multi-
meter probes at one polarity and less so if you change the Multi-meter probe polarity.
6.1.4 Antenna Surge Suppressor
If GPS Surge Suppressor kit is available with purchase order, user should mount it in line with the an-
tenna cable. Additional information on grounding GPS antennas, and grounding in general, are avail-
able from Masibus Customer Support division (Kit P/N :m-LA-01).
