User Manual

Strata Operations Guide
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15 -
* * * CAUTION * * *
DC Voltages Present on Coaxial Cable
Center Conductors
Use Caution
For those Strata TX configurations that employ 2 or 3 modules, e.g., TCU + TXU
+ HPU, etc., the TCU and/or TXU may be used to power adjacent modules by
superimposing DC voltage on the interconnecting coaxial cable center conductor.
This feature is activated using the Strata TX front panel controls and remains in
effect until subsequently modified by the user. The voltages involved range from
+ 12 to + 48 volts DC (DC input voltage).
To avoid damaging radio and test equipment input circuitry, be certain you either
remove or isolate superimposed DC voltages from interconnecting coaxial cables
where necessary to protect externally connected equipment.
In the case of the TXU-to-HPU RF coaxial cable connection, the center conductor
will have DC voltages superimposed on the RF cable center conductor in order to
power the HPU. If the TXU RF output is connected directly to an antenna or test
equipment, be certain to disable the HPU On feature and therefore remove the DC
voltage superimposed on the TXU RF output.
The Strata TCU “Signal In” BNC connector on the rear of the TCU module is
susceptible to damage if DC is present on the center conductor. Take care that the
TXU-to-TCU interconnecting coaxial cable (if used) is not inadvertently connected
to the “Signal In” connector instead of the “Signal Out” connector. Please see the
image on the following page for additional details.