Microwave Data Systems MDS 4310, Установка, эксплуатация и техническое обслуживание на месте

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MDS 05-2415A01, Rev. A FIELD TESTS & ADJUSTMENTS 4-3
shown in Figure 4-1. The transceiver’s
INTERFACE
connector must be configured for
RS-232 operation for proper operation of the emulator. (See “Special Instructions
for Radios Configured as TTL” below if your radio has been configured for TTL.)
NOTE
As an alternative to a Data Terminal Emulator, a “breakout
box” or jumpers can be attached to the transceiver’s
INTERFACE
connector and configured with the proper connections as
shown in Figure 4-1.
Special Instructions for Radios Configured as TTL
In most cases, a data terminal emulator can be plugged directly into the
radio’s INTERFACE connector and used immediately. However, in some
cases, the INTERFACE connector may have been previously configured
for TTL operation (as opposed to the more common RS-232 format) using
the radio’s J11 jumper field.
If you are unsure of which configuration you have, look at J11 on the
transceiver’s motherboard. In an RS-232 radio, all pins on J11 will be
empty (open), with the possible exception of a jumper on Pins 13 and 14
(LEDs enabled). By contrast, a TTL radio will have jumpers installed on
all
pins of J11, with the possible exception of Pins 13 and 14.
If your radio is configured for TTL, an optional TTL to RS-232 adapter plug
is available from MDS (P/N 03-2223A01) to allow connection of the Data
Terminal Emulator, an HHT or other RS-232 equipment. This unit plugs
between the transceiver’s INTERFACE connector and the external
equipment, making the transceiver appear as an RS-232 device. Contact
the factory for ordering information.
If the TTL to RS-232 adapter plug is not available, it is also possible to
temporarily reconfigure the INTERFACE connector for RS-232 operation
by removing the jumpers on J11. (See Table 2-4 for proper jumper
placement.) When testing is complete, J11 can be restored to its TTL
configuration.
CONSTRUCTING A DATA TERMINAL EMULATOR
Introduction
The right side of Figure 4-1 shows the proper wiring for a simple data terminal emulator.
There are two ways to construct the Data Terminal Emulator; both techniques are electrically
identical and use common parts available from most electronic parts supply stores. The
difference is in the packaging of the two units.
Emulator Design #1
Method 1 requires two small toggle switches (SW1 & SW2), and a DB-25 male connector
with a cover that is large enough to mount the toggle switches inside it. (See the top part of
Figure 4-2.)
Emulator Design #2
Method 2 requires two toggle switches (SW1 & SW2), a DB-25 male connector, a short
length of three-conductor cable, and a small enclosure. (See the lower part of Figure 4-2.)