DLS DLS 400A, Operating Manual

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Appendix D
Page 202
less noise, and does not give unwanted reflections. Screened twisted pair is better because
it picks up less noise, and there is less chance of unwanted crosstalk.
Note that when the noise generator is applied to the line it must not disturb the signals
already on the line. Otherwise communication between the modems would be altered. For
this reason, the noise generator has a high output impedance. Some people like to look at it
as a current generator rather than a voltage generator. All present Consultronics generators
have an output impedance of 4 kohms or more.
Depending on the simulator type, connectors on the DLS may be an RJ45 jack, a Siemens
CF connector (which will also take banana plugs) a bantam jack, a terminal strip, or some
combination of these. Note that the bantam jack goes under several names, such as mini-
bantam, mini 310, bantam telco jack. For the DLS 400, there are bantam jacks front and
back and CF connectors on the front. On side A of the unit, all 3 of these connectors are
equivalent, and internally connected. You may connect to any or all of them. The same is
true for side B. Of course, if you connect to two of them, this joins the two plugs electri-
cally together.
Sometimes you may want to connect the noise generator from, say, an NSA 400J to a
wireline simulator such as a DLS 400, if it is not equipped with its own impairments gen-
erator. This is easy. Connect the DLS 400, modems, and error rate testers together in the
usual way. At the side of the DLS 400 where you want added impairments, plug in one
end of your connecting wire to one of the spare connectors on the DLS 400. It is either a
bantam jack or a CF connector. Plug the other end in to the NSA 400J. The diagram shows
the connections together with connections internal to the NSA.
N o ise
G en
Test
S e t
M od em M od em
W ire lin e
Test
S e t
D L S 4 00 J