Communication solutions for power utilities
1U SHELF TYPE MAS-2
WITH ASYNCHRONOUS PROGRAMMABLE MODEM MAFP - Rev. 9 (January 2018)
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S2
Selection of output impedance.
A:
600
B:
High impedance
S1
Selection of input impedance.
A:
600
B:
High impedance
P4, P5
By performing a jumper between pin 1 of P4 and pin 1 of P5, the equipment,
once initialized, leaves normal operation and starts to work in an operating
mode in which the firmware of the MAFP module can be updated from a
HyperTerminal session.
4.4
ADJUSTMENTS
4.4.1
Transmit-level adjustment
The process for carrying out the transmit-level adjustment is as follows:
1.
If the modem is not connected to the transmission line, before carrying out the
adjustment, load the transmitter output with a 600
resistor.
2.
Select the range required for the transmission level by means of jumper S4.
3.
The fine adjustment of the transmit level is carried out by means of potentiometer XMT
ADJUSTMENT on the front plate and by measuring the amplitude of the signal at the Tx
line connection terminals situated on the back of the shelf (see Figure 19).
4.4.2
Receive-level adjustment
The process for carrying out the adjustment of the receiver sensitivity is the following:
1.
Connect the modem to the transmission line with the other end transmitting.
2.
The level adjustment is carried out by means of potentiometer RCV ADJUSTMENT on
the front plate. Turn the potentiometer until a level of 0.5 V
pp
is measured at the test
points RCV MEASUREMENT also situated on the front plate. It may be necessary to
change the scale by putting jumper S3 in another position.
3.
Check that the CD LED remains lit.